.eslintrc

@@ -0,0 +1,6 @@
+{
+    "extends": "scality",
+    "parserOptions": {
+        "ecmaVersion": 2020
+    }
+}

.github/dependabot.yml

@@ -0,0 +1,10 @@
+---
+version: 2
+updates:
+  - package-ecosystem: npm
+    directory: "/"
+    schedule:
+      interval: daily
+      time: "13:00"
+    open-pull-requests-limit: 10
+    target-branch: "development/7.4"

.github/workflows/codeql.yaml

@@ -0,0 +1,25 @@
+---
+name: codeQL
+
+on:
+  push:
+    branches: [development/*, stabilization/*, hotfix/*]
+  pull_request:
+    branches: [development/*, stabilization/*, hotfix/*]
+  workflow_dispatch:
+
+jobs:
+  analyze:
+    name: Static analysis with CodeQL
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: javascript, typescript
+
+      - name: Build and analyze
+        uses: github/codeql-action/analyze@v3

.github/workflows/dependency-review.yaml

@@ -0,0 +1,16 @@
+---
+name: dependency review
+
+on:
+  pull_request:
+    branches: [development/*, stabilization/*, hotfix/*]
+
+jobs:
+  dependency-review:
+    runs-on: ubuntu-latest
+    steps:
+      - name: 'Checkout Repository'
+        uses: actions/checkout@v4
+
+      - name: 'Dependency Review'
+        uses: actions/dependency-review-action@v4

.github/workflows/tests.yaml

@@ -0,0 +1,82 @@
+---
+name: tests
+
+on:
+  push:
+    branches-ignore:
+    - 'development/**'
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    services:
+      # Label used to access the service container
+      redis:
+        # Docker Hub image
+        image: redis
+        # Set health checks to wait until redis has started
+        options: >-
+          --health-cmd "redis-cli ping"
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
+        ports:
+          # Maps port 6379 on service container to the host
+          - 6379:6379
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v4
+    - uses: actions/setup-node@v4
+      with:
+        node-version: '16'
+        cache: 'yarn'
+    - name: install dependencies
+      run: yarn install --frozen-lockfile --prefer-offline --network-concurrency 1
+      continue-on-error: true # TODO ARSN-97 Remove it when no errors in TS
+    - name: lint yaml
+      run: yarn --silent lint_yml
+    - name: lint javascript
+      run: yarn --silent lint --max-warnings 0
+    - name: lint markdown
+      run: yarn --silent lint_md
+    - name: add hostname
+      run: |
+        sudo sh -c "echo '127.0.0.1 testrequestbucket.localhost' >> /etc/hosts"
+    - name: test and coverage
+      run: yarn --silent coverage
+    - name: run functional tests
+      run: yarn ft_test
+    - uses: codecov/codecov-action@v4
+      with:
+        token: ${{ secrets.CODECOV_TOKEN }}
+    - name: run executables tests
+      run: yarn install && yarn test
+      working-directory: 'lib/executables/pensieveCreds/'
+
+  compile:
+    name: Compile and upload build artifacts
+    needs: test
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v4
+    - name: Install NodeJS
+      uses: actions/setup-node@v4
+      with:
+        node-version: '16'
+        cache: yarn
+    - name: Install dependencies
+      run: yarn install --frozen-lockfile --prefer-offline
+      continue-on-error: true # TODO ARSN-97 Remove it when no errors in TS
+    - name: Compile
+      run: yarn build
+      continue-on-error: true # TODO ARSN-97 Remove it when no errors in TS
+    - name: Upload artifacts
+      uses: scality/action-artifacts@v4
+      with:
+        url: https://artifacts.scality.net
+        user: ${{ secrets.ARTIFACTS_USER }}
+        password: ${{ secrets.ARTIFACTS_PASSWORD }}
+        source: ./build
+        method: upload
+      if: success()

.gitignore

@@ -0,0 +1,18 @@
+# Logs
+*.log
+
+# Dependency directory
+node_modules/
+*/node_modules/
+
+# Build executables
+*-win.exe
+*-linux
+*-macos
+
+# Coverage
+coverage/
+.nyc_output/
+
+# TypeScript
+build/

.swcrc

@@ -0,0 +1,12 @@
+{
+  "$schema": "https://swc.rs/schema.json",
+  "jsc": {
+    "parser": {
+      "syntax": "typescript"
+    },
+    "target": "es2017"
+  },
+  "module": {
+    "type": "commonjs"
+  }
+}

.yamllint

@@ -0,0 +1,3 @@
+extends: default
+rules:
+  document-start: {level: error}

CONTRIBUTING.md

@@ -0,0 +1,5 @@
+# Contributing rules
+
+Please follow the
+[Contributing Guidelines](
+https://github.com/scality/Guidelines/blob/master/CONTRIBUTING.md).

LICENSE

@@ -176,18 +176,7 @@
 
    END OF TERMS AND CONDITIONS
 
-   APPENDIX: How to apply the Apache License to your work.
-
-      To apply the Apache License to your work, attach the following
-      boilerplate notice, with the fields enclosed by brackets "[]"
-      replaced with your own identifying information. (Don't include
-      the brackets!)  The text should be enclosed in the appropriate
-      comment syntax for the file format. We also recommend that a
-      file or class name and description of purpose be included on the
-      same "printed page" as the copyright notice for easier
-      identification within third-party archives.
-
-   Copyright [yyyy] [name of copyright owner]
+   Copyright 2016 Scality
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.

README.md

@@ -0,0 +1,150 @@
+# Arsenal
+
+[![codecov](https://codecov.io/gh/scality/Arsenal/branch/development/8.1/graph/badge.svg?token=X0esXhJSwb)](https://codecov.io/gh/scality/Arsenal)
+
+Common utilities for the S3 project components
+
+Within this repository, you will be able to find the shared libraries for the
+multiple components making up the whole Project.
+
+* [Guidelines](#guidelines)
+* [Shuffle](#shuffle) to shuffle an array.
+* [Errors](#errors) load an object of errors instances.
+    - [errors/arsenalErrors.json](errors/arsenalErrors.json)
+
+## Guidelines
+
+Please read our coding and workflow guidelines at
+[scality/Guidelines](https://github.com/scality/Guidelines).
+
+### Contributing
+
+In order to contribute, please follow the
+[Contributing Guidelines](
+https://github.com/scality/Guidelines/blob/master/CONTRIBUTING.md).
+
+## Shuffle
+
+### Usage
+
+``` js
+import { shuffle } from 'arsenal';
+
+let array = [1, 2, 3, 4, 5];
+
+shuffle(array);
+
+console.log(array);
+
+//[5, 3, 1, 2, 4]
+```
+
+## Errors
+
+### Usage
+
+``` js
+import { errors } from 'arsenal';
+
+console.log(errors.AccessDenied);
+
+//{ [Error: AccessDenied]
+//    code: 403,
+//    description: 'Access Denied',
+//    AccessDenied: true }
+
+```
+
+## Clustering
+
+The clustering class can be used to set up a cluster of workers. The class will
+create at least 1 worker, will log any worker event (started, exited).
+The class also provides a watchdog which restarts the workers in case of
+failure until the stop() method is called.
+
+### Usage
+
+#### Simple
+
+```
+import { Clustering } from 'arsenal';
+
+const cluster = new Clustering(clusterSize, logger);
+cluster.start(current => {
+    // Put here the logic of every worker.
+    // 'current' is the Clustering instance, worker id is accessible by
+    // current.getIndex()
+});
+```
+
+The callback will be called every time a worker is started/restarted.
+
+#### Handle exit
+
+```
+import { Clustering } from 'arsenal';
+
+const cluster = new Clustering(clusterSize, logger);
+cluster.start(current => {
+    // Put here the logic of every worker.
+    // 'current' is the Clustering instance, worker id is accessible by
+    // current.getIndex()
+}).onExit(current => {
+    if (current.isMaster()) {
+        // Master process exiting
+    } else {
+        const id = current.getIndex();
+        // Worker (id) exiting
+    }
+});
+```
+
+You can handle exit event on both master and workers by calling the
+'onExit' method and setting the callback. This allows release of resources
+or save state before exiting the process.
+
+#### Silencing a signal
+
+```
+import { Clustering } from 'arsenal';
+
+const cluster = new Clustering(clusterSize, logger);
+cluster.start(current => {
+    // Put here the logic of every worker.
+    // 'current' is the Clustering instance, worker id is accessible by
+    // current.getIndex()
+}).onExit((current, signal) => {
+    if (signal !== 'SIGTERM') {
+        process.exit(current.getStatus());
+    }
+});
+```
+
+You can silence stop signals, by simply not exiting on the exit callback
+
+#### Shutdown timeout
+
+```
+import { Clustering } from 'arsenal';
+
+const cluster = new Clustering(clusterSize, logger, 1000);
+cluster.start(current => {
+    // Put here the logic of every worker.
+    // 'current' is the Clustering instance, worker id is accessible by
+    // current.getIndex()
+}).onExit((current, signal) => {
+    if (signal === 'SIGTERM') {
+        // releasing resources
+    }
+});
+```
+
+By default, the shutdown timeout is set to 5000 milliseconds. This timeout is
+used only when you explicitly call the stop() method. This window is
+used to let the application release its resources, but if timeout occurs
+before the application has finished it's cleanup, a 'SIGKILL' signal is send
+to the process (which results in an immediate termination, and this signal
+can't be caught).
+
+[badgepub]: https://circleci.com/gh/scality/Arsenal.svg?style=svg
+[badgepriv]: http://ci.ironmann.io/gh/scality/Arsenal.svg?style=svg&circle-token=c3d2570682cba6763a97ea0bc87521941413d75c

babel.config.js

@@ -0,0 +1,6 @@
+module.exports = {
+    presets: [
+        ['@babel/preset-env', { targets: { node: 'current' } }],
+        '@babel/preset-typescript',
+    ],
+};

badge.svg

@@ -1,17 +0,0 @@
-<svg xmlns="http://www.w3.org/2000/svg" width="102" height="20">
-  <script/>
-  <linearGradient id="a" x2="0" y2="100%">
-    <stop offset="0" stop-color="#bbb" stop-opacity=".1"/>
-    <stop offset="1" stop-opacity=".1"/>
-  </linearGradient>
-  <rect rx="3" width="102" height="20" fill="#555"/>
-  <rect rx="3" x="64" width="38" height="20" fill="#dab226"/>
-  <path fill="#dab226" d="M64 0h4v20h-4z"/>
-  <rect rx="3" width="102" height="20" fill="url(#a)"/>
-  <g fill="#fff" text-anchor="middle" font-family="DejaVu Sans,Verdana,Geneva,sans-serif" font-size="11">
-    <text x="32" y="15" fill="#010101" fill-opacity=".3">document</text>
-    <text x="32" y="14">document</text>
-    <text x="82.5" y="15" fill="#010101" fill-opacity=".3">87%</text>
-    <text x="82.5" y="14">87%</text>
-  </g>
-</svg>

circle.yml

@@ -0,0 +1,28 @@
+---
+general:
+  branches:
+    ignore:
+      - /^ultron\/.*/  # Ignore ultron/* branches
+
+machine:
+  node:
+    version: 6.13.1
+  services:
+    - redis
+  environment:
+    CXX: g++-4.9
+
+dependencies:
+  override:
+    - rm -rf node_modules
+    - npm install
+    - sudo pip install yamllint
+
+test:
+  override:
+    - npm run --silent lint_yml
+    - npm run --silent lint -- --max-warnings 0
+    - npm run --silent lint_md
+    - npm run --silent test
+    - npm run ft_test
+    - cd lib/executables/pensieveCreds && npm install && npm test

coverage.json

@@ -1,19 +0,0 @@
-{
-  "coverage": "87.23%",
-  "expectCount": 47,
-  "actualCount": 41,
-  "files": {
-    "kinetic/Kinetic.js": {
-      "expectCount": 47,
-      "actualCount": 41,
-      "undocumentLines": [
-        66,
-        13,
-        41,
-        683,
-        15,
-        25
-      ]
-    }
-  }
-}

css/prettify-tomorrow.css

@@ -1,132 +0,0 @@
-/* Tomorrow Theme */
-/* Original theme - https://github.com/chriskempson/tomorrow-theme */
-/* Pretty printing styles. Used with prettify.js. */
-/* SPAN elements with the classes below are added by prettyprint. */
-/* plain text */
-.pln {
-  color: #4d4d4c; }
-
-@media screen {
-  /* string content */
-  .str {
-    color: #718c00; }
-
-  /* a keyword */
-  .kwd {
-    color: #8959a8; }
-
-  /* a comment */
-  .com {
-    color: #8e908c; }
-
-  /* a type name */
-  .typ {
-    color: #4271ae; }
-
-  /* a literal value */
-  .lit {
-    color: #f5871f; }
-
-  /* punctuation */
-  .pun {
-    color: #4d4d4c; }
-
-  /* lisp open bracket */
-  .opn {
-    color: #4d4d4c; }
-
-  /* lisp close bracket */
-  .clo {
-    color: #4d4d4c; }
-
-  /* a markup tag name */
-  .tag {
-    color: #c82829; }
-
-  /* a markup attribute name */
-  .atn {
-    color: #f5871f; }
-
-  /* a markup attribute value */
-  .atv {
-    color: #3e999f; }
-
-  /* a declaration */
-  .dec {
-    color: #f5871f; }
-
-  /* a variable name */
-  .var {
-    color: #c82829; }
-
-  /* a function name */
-  .fun {
-    color: #4271ae; } }
-/* Use higher contrast and text-weight for printable form. */
-@media print, projection {
-  .str {
-    color: #060; }
-
-  .kwd {
-    color: #006;
-    font-weight: bold; }
-
-  .com {
-    color: #600;
-    font-style: italic; }
-
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-    font-weight: bold; }
-
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-    color: #044; }
-
-  .pun, .opn, .clo {
-    color: #440; }
-
-  .tag {
-    color: #006;
-    font-weight: bold; }
-
-  .atn {
-    color: #404; }
-
-  .atv {
-    color: #060; } }
-/* Style */
-/*
-pre.prettyprint {
-  background: white;
-  font-family: Consolas, Monaco, 'Andale Mono', monospace;
-  font-size: 12px;
-  line-height: 1.5;
-  border: 1px solid #ccc;
-  padding: 10px; }
-*/
-
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-ol.linenums {
-  margin-top: 0;
-  margin-bottom: 0; }
-
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-li.L0,
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-li.L2,
-li.L3,
-li.L4,
-li.L5,
-li.L6,
-li.L7,
-li.L8,
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-  /* */ }
-
-/* Alternate shading for lines */
-li.L1,
-li.L3,
-li.L5,
-li.L7,
-li.L9 {
-  /* */ }

css/style.css

@@ -1,944 +0,0 @@
-@import url(https://fonts.googleapis.com/css?family=Roboto:400,300,700);
-
-* {
-  margin: 0;
-  padding: 0;
-  text-decoration: none;
-}
-
-html
-{
-  font-family: 'Roboto', sans-serif;
-  overflow: auto;
-  font-size: 14px;
-  /*color: #4d4e53;*/
-  color: rgba(0, 0, 0, .68);
-  background-color: #fff;
-}
-
-a {
-  /*color: #0095dd;*/
-  /*color:rgb(37, 138, 175);*/
-  color: #039BE5;
-}
-
-code a:hover {
-  text-decoration: underline;
-}
-
-ul, ol {
-  padding-left: 20px;
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-
-ul li {
-  list-style: disc;
-  margin: 4px 0;
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-
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-  margin: 4px 0;
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-  font-size: 34px;
-  font-weight: 300;
-  border-bottom: solid 1px #ddd;
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-  margin-top: 24px;
-  margin-bottom: 10px;
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-  margin-bottom: 12px;
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-  padding: 4px;
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-}
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documentation/BucketInfoModelVersion.md

@@ -0,0 +1,260 @@
+# BucketInfo Model Version History
+
+## Model Version 0/1
+
+### Properties
+
+``` javascript
+this._acl = aclInstance;
+this._name = name;
+this._owner = owner;
+this._ownerDisplayName = ownerDisplayName;
+this._creationDate = creationDate;
+```
+
+### Usage
+
+No explicit references in the code since mdBucketModelVersion
+property not added until Model Version 2
+
+## Model Version 2
+
+### Properties Added
+
+``` javascript
+this._mdBucketModelVersion = mdBucketModelVersion || 0
+this._transient = transient || false;
+this._deleted = deleted || false;
+```
+
+### Usage
+
+Used to determine which splitter to use ( < 2 means old splitter)
+
+## Model version 3
+
+### Properties Added
+
+```
+this._serverSideEncryption = serverSideEncryption || null;
+```
+
+### Usage
+
+Used to store the server bucket encryption info
+
+## Model version 4
+
+### Properties Added
+
+```javascript
+this._locationConstraint = LocationConstraint || null;
+```
+
+### Usage
+
+Used to store the location constraint of the bucket
+
+## Model version 5
+
+### Properties Added
+
+```javascript
+this._websiteConfiguration = websiteConfiguration || null;
+this._cors = cors || null;
+```
+
+### Usage
+
+Used to store the bucket website configuration info
+and to store CORS rules to apply to cross-domain requests
+
+## Model version 6
+
+### Properties Added
+
+```javascript
+this._lifecycleConfiguration = lifecycleConfiguration || null;
+```
+
+### Usage
+
+Used to store the bucket lifecycle configuration info
+
+## Model version 7
+
+### Properties Added
+
+```javascript
+this._uid = uid || uuid();
+```
+
+### Usage
+
+Used to set a unique identifier on a bucket
+
+## Model version 8
+
+### Properties Added
+
+```javascript
+this._readLocationConstraint = readLocationConstraint || null;
+```
+
+### Usage
+
+Used to store default read location of the bucket
+
+## Model version 9
+
+### Properties Added
+
+```javascript
+this._isNFS = isNFS || null;
+```
+
+### Usage
+
+Used to determine whether the bucket may be accessed through NFS
+
+## Model version 10
+
+### Properties Added
+
+```javascript
+this._ingestion = ingestionConfig || null;
+```
+
+### Usage
+
+Used to store the ingestion status of a bucket
+
+## Model version 11
+
+### Properties Added
+
+```javascript
+this._azureInfo = azureInfo || null;
+```
+
+### Usage
+
+Used to store Azure storage account specific information
+
+## Model version 12
+
+### Properties Added
+
+```javascript
+this._objectLockEnabled = objectLockEnabled || false;
+this._objectLockConfiguration = objectLockConfiguration || null;
+```
+
+### Usage
+
+Used to determine whether object lock capabilities are enabled on a bucket and
+to store the object lock configuration of the bucket
+
+## Model version 13
+
+### Properties Added
+
+```javascript
+this._notificationConfiguration = notificationConfiguration || null;
+```
+
+### Usage
+
+Used to store the bucket notification configuration info
+
+## Model version 14
+
+### Properties Added
+
+```javascript
+this._serverSideEncryption.configuredMasterKeyId = configuredMasterKeyId || undefined;
+```
+
+### Usage
+
+Used to store the users configured KMS key id
+
+## Model version 15
+
+### Properties Added
+
+```javascript
+this._tags = tags || null;
+```
+
+The Tag Set of a bucket is an array of objects with Key and Value:
+
+```javascript
+[
+    {
+        Key: 'something',
+        Value: 'some_data'
+    }
+]
+```
+
+## Model version 16
+
+### Properties Added
+
+```javascript
+this._capabilities = capabilities || undefined;
+```
+
+For capacity-enabled buckets, contains the following data:
+
+```javascript
+{
+    _capabilities: {
+        VeeamSOSApi?: {
+            SystemInfo?: {
+                ProtocolVersion: String,
+                ModelName: String,
+                ProtocolCapabilities: {
+                    CapacityInfo: Boolean,
+                    UploadSessions: Boolean,
+                    IAMSTS: Boolean,
+                },
+                APIEndpoints: {
+                    IAMEndpoint: String,
+                    STSEndpoint: String,
+                },
+                SystemRecommendations?: {
+                    S3ConcurrentTaskLimit: Number,
+                    S3MultiObjectDelete: Number,
+                    StorageCurrentTasksLimit: Number,
+                    KbBlockSize: Number,
+                }
+                LastModified?: String,
+            },
+            CapacityInfo?: {
+                Capacity: Number,
+                Available: Number,
+                Used: Number,
+                LastModified?: String,
+            },
+        }
+    },
+}
+```
+
+### Usage
+
+Used to store bucket tagging
+
+## Model version 17
+
+### Properties Added
+
+```javascript
+this._quotaMax = quotaMax || 0;
+```
+
+### Usage
+
+Used to store bucket quota

documentation/listingAlgos/delimiter.md

@@ -0,0 +1,27 @@
+# Delimiter
+
+The Delimiter class handles raw listings from the database with an
+optional delimiter, and fills in a curated listing with "Contents" and
+"CommonPrefixes" as a result.
+
+## Expected Behavior
+
+- only lists keys belonging to the given **prefix** (if provided)
+
+- groups listed keys that have a common prefix ending with a delimiter
+  inside CommonPrefixes
+
+- can take a **marker** or **continuationToken** to list from a specific key
+
+- can take a **maxKeys** parameter to limit how many keys can be returned
+
+## State Chart
+
+- States with grey background are *Idle* states, which are waiting for
+  a new listing key
+
+- States with blue background are *Processing* states, which are
+  actively processing a new listing key passed by the filter()
+  function
+
+![Delimiter State Chart](./pics/delimiterStateChart.svg)

documentation/listingAlgos/delimiterMaster.md

@@ -0,0 +1,45 @@
+# DelimiterMaster
+
+The DelimiterMaster class handles raw listings from the database of a
+versioned or non-versioned bucket with an optional delimiter, and
+fills in a curated listing with "Contents" and "CommonPrefixes" as a
+result.
+
+## Expected Behavior
+
+- only lists latest versions of versioned buckets
+
+- only lists keys belonging to the given **prefix** (if provided)
+
+- does not list latest versions that are delete markers
+
+- groups listed keys that have a common prefix ending with a delimiter
+  inside CommonPrefixes
+
+- can take a **marker** or **continuationToken** to list from a specific key
+
+- can take a **maxKeys** parameter to limit how many keys can be returned
+
+- reconciles internal PHD keys with the next version (those are
+  created when a specific version that is the latest version is
+  deleted)
+
+- skips internal keys like replay keys
+
+## State Chart
+
+- States with grey background are *Idle* states, which are waiting for
+  a new listing key
+
+- States with blue background are *Processing* states, which are
+  actively processing a new listing key passed by the filter()
+  function
+
+### Bucket Vformat=v0
+
+![DelimiterMaster State Chart for v0 format](./pics/delimiterMasterV0StateChart.svg)
+
+### Bucket Vformat=v1
+
+For buckets in versioning key format **v1**, the algorithm used is the
+one from [Delimiter](delimiter.md).

documentation/listingAlgos/delimiterVersions.md

@@ -0,0 +1,33 @@
+# DelimiterVersions
+
+The DelimiterVersions class handles raw listings from the database of a
+versioned or non-versioned bucket with an optional delimiter, and
+fills in a curated listing with "Versions" and "CommonPrefixes" as a
+result.
+
+## Expected Behavior
+
+- lists individual distinct versions of versioned buckets
+
+- only lists keys belonging to the given **prefix** (if provided)
+
+- groups listed keys that have a common prefix ending with a delimiter
+  inside CommonPrefixes
+
+- can take a **keyMarker** and optionally a **versionIdMarker** to
+  list from a specific key or version
+
+- can take a **maxKeys** parameter to limit how many keys can be returned
+
+- skips internal keys like replay keys
+
+## State Chart
+
+- States with grey background are *Idle* states, which are waiting for
+  a new listing key
+
+- States with blue background are *Processing* states, which are
+  actively processing a new listing key passed by the filter()
+  function
+
+![DelimiterVersions State Chart](./pics/delimiterVersionsStateChart.svg)

documentation/listingAlgos/pics/delimiterMasterV0StateChart.dot

@@ -0,0 +1,45 @@
+digraph {
+  node [shape="box",style="filled,rounded",fontsize=16,fixedsize=true,width=3];
+  edge [fontsize=14];
+  rankdir=TB;
+
+  START [shape="circle",width=0.2,label="",style="filled",fillcolor="black"]
+  END [shape="circle",width=0.2,label="",style="filled",fillcolor="black",peripheries=2]
+
+  node [fillcolor="lightgrey"];
+  "NotSkippingPrefixNorVersions.Idle" [label="NotSkippingPrefixNorVersions",group="NotSkippingPrefixNorVersions",width=4];
+  "SkippingPrefix.Idle" [label="SkippingPrefix",group="SkippingPrefix"];
+  "SkippingVersions.Idle" [label="SkippingVersions",group="SkippingVersions"];
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+  "SkippingVersions.Processing" [label="SkippingVersions",group="SkippingVersions"];
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+  "SkippingVersions.Idle" -> "SkippingVersions.Processing" [label="filter(key, value)"]
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+  "NotSkippingPrefixNorVersions.Processing" -> "WaitVersionAfterPHD.Idle" [label="[Version.isPHD(value)]\n-> FILTER_ACCEPT"]
+  "NotSkippingPrefixNorVersions.Processing" -> "SkippingPrefix.Idle" [label="[key.startsWith(<ReplayPrefix>)]\n/ prefix <- <ReplayPrefix>\n-> FILTER_SKIP"]
+  "NotSkippingPrefixNorVersions.Processing" -> END [label="[isListableKey(key, value) and\nKeys == maxKeys]\n-> FILTER_END"]
+  "NotSkippingPrefixNorVersions.Processing" -> "SkippingPrefix.Idle" [label="[isListableKey(key, value) and\nnKeys < maxKeys and\nhasDelimiter(key)]\n/ prefix <- prefixOf(key)\n/ CommonPrefixes.append(prefixOf(key))\n-> FILTER_ACCEPT"]
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+
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+  "SkippingPrefix.Processing" -> "NotSkippingPrefixNorVersions.Processing" [label="[not key.startsWith(prefix)]"]
+
+  "SkippingVersions.Processing" -> "SkippingVersions.Idle" [label="[isVersionKey(key)]\n-> FILTER_SKIP"]
+  "SkippingVersions.Processing" -> "NotSkippingPrefixNorVersions.Processing" [label="[not isVersionKey(key)]"]
+
+  "WaitVersionAfterPHD.Processing" -> "NotSkippingPrefixNorVersions.Processing" [label="[isVersionKey(key) and master(key) == PHDkey]\n/ key <- master(key)"]
+  "WaitVersionAfterPHD.Processing" -> "NotSkippingPrefixNorVersions.Processing" [label="[not isVersionKey(key) or master(key) != PHDkey]"]
+}

documentation/listingAlgos/pics/delimiterMasterV0StateChart.svg

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+<title>SkippingVersions.Processing&#45;&gt;NotSkippingPrefixNorVersions.Processing</title>
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+</g>
+</g>
+</svg>

documentation/listingAlgos/pics/delimiterStateChart.dot

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+  edge [fontsize=14];
+  rankdir=TB;
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+  END [shape="circle",width=0.2,label="",style="filled",fillcolor="black",peripheries=2]
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+  "NeverSkipping.Idle" [label="NeverSkipping",group="NeverSkipping"];
+  "NotSkippingPrefix.Idle" [label="NotSkippingPrefix",group="NotSkippingPrefix"];
+  "SkippingPrefix.Idle" [label="SkippingPrefix",group="SkippingPrefix"];
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+  node [fillcolor="lightblue"];
+  "NeverSkipping.Processing" [label="NeverSkipping",group="NeverSkipping"];
+  "NotSkippingPrefix.Processing" [label="NotSkippingPrefix",group="NotSkippingPrefix"];
+  "SkippingPrefix.Processing" [label="SkippingPrefix",group="SkippingPrefix"];
+
+  START -> "NotSkipping.Idle"
+  "NotSkipping.Idle" -> "NeverSkipping.Idle" [label="[delimiter == undefined]"]
+  "NotSkipping.Idle" -> "NotSkippingPrefix.Idle" [label="[delimiter == '/']"]
+
+  "NeverSkipping.Idle" -> "NeverSkipping.Processing" [label="filter(key, value)"]
+  "NotSkippingPrefix.Idle" -> "NotSkippingPrefix.Processing" [label="filter(key, value)"]
+  "SkippingPrefix.Idle" -> "SkippingPrefix.Processing" [label="filter(key, value)"]
+
+  "NeverSkipping.Processing" -> END [label="[nKeys == maxKeys]\n-> FILTER_END"]
+  "NeverSkipping.Processing" -> "NeverSkipping.Idle" [label="[nKeys < maxKeys]\n/ Contents.append(key, value)\n -> FILTER_ACCEPT"]
+  "NotSkippingPrefix.Processing" -> END [label="[nKeys == maxKeys]\n -> FILTER_END"]
+  "NotSkippingPrefix.Processing" -> "SkippingPrefix.Idle" [label="[nKeys < maxKeys and hasDelimiter(key)]\n/ prefix <- prefixOf(key)\n/ CommonPrefixes.append(prefixOf(key))\n-> FILTER_ACCEPT"]
+  "NotSkippingPrefix.Processing" -> "NotSkippingPrefix.Idle" [label="[nKeys < maxKeys and not hasDelimiter(key)]\n/ Contents.append(key, value)\n -> FILTER_ACCEPT"]
+  "SkippingPrefix.Processing" -> "SkippingPrefix.Idle" [label="[key.startsWith(prefix)]\n-> FILTER_SKIP"]
+  "SkippingPrefix.Processing" -> "NotSkippingPrefix.Processing" [label="[not key.startsWith(prefix)]"]
+}

documentation/listingAlgos/pics/delimiterStateChart.svg

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+</g>
+<!-- NotSkipping.Idle -->
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+<text text-anchor="middle" x="283" y="-452.2" font-family="Times,serif" font-size="16.00">NotSkipping</text>
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+<!-- START&#45;&gt;NotSkipping.Idle -->
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+<ellipse fill="none" stroke="black" cx="196" cy="-120" rx="11" ry="11"/>
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+<!-- NeverSkipping.Idle -->
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+<title>NeverSkipping.Idle</title>
+<path fill="lightgrey" stroke="black" d="M262,-387C262,-387 70,-387 70,-387 64,-387 58,-381 58,-375 58,-375 58,-363 58,-363 58,-357 64,-351 70,-351 70,-351 262,-351 262,-351 268,-351 274,-357 274,-363 274,-363 274,-375 274,-375 274,-381 268,-387 262,-387"/>
+<text text-anchor="middle" x="166" y="-365.2" font-family="Times,serif" font-size="16.00">NeverSkipping</text>
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+<!-- NotSkipping.Idle&#45;&gt;NeverSkipping.Idle -->
+<g id="edge2" class="edge">
+<title>NotSkipping.Idle&#45;&gt;NeverSkipping.Idle</title>
+<path fill="none" stroke="black" d="M216.5,-437.82C206.51,-433.18 196.91,-427.34 189,-420 182.25,-413.74 177.33,-405.11 173.81,-396.79"/>
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+</g>
+<!-- NotSkippingPrefix.Idle -->
+<g id="node5" class="node">
+<title>NotSkippingPrefix.Idle</title>
+<path fill="lightgrey" stroke="black" d="M496,-387C496,-387 304,-387 304,-387 298,-387 292,-381 292,-375 292,-375 292,-363 292,-363 292,-357 298,-351 304,-351 304,-351 496,-351 496,-351 502,-351 508,-357 508,-363 508,-363 508,-375 508,-375 508,-381 502,-387 496,-387"/>
+<text text-anchor="middle" x="400" y="-365.2" font-family="Times,serif" font-size="16.00">NotSkippingPrefix</text>
+</g>
+<!-- NotSkipping.Idle&#45;&gt;NotSkippingPrefix.Idle -->
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+<title>NotSkipping.Idle&#45;&gt;NotSkippingPrefix.Idle</title>
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+<text text-anchor="middle" x="442.5" y="-408.8" font-family="Times,serif" font-size="14.00">[delimiter == &#39;/&#39;]</text>
+</g>
+<!-- NeverSkipping.Processing -->
+<g id="node7" class="node">
+<title>NeverSkipping.Processing</title>
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+<text text-anchor="middle" x="108" y="-248.2" font-family="Times,serif" font-size="16.00">NeverSkipping</text>
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+<!-- NeverSkipping.Idle&#45;&gt;NeverSkipping.Processing -->
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documentation/listingAlgos/pics/delimiterVersionsStateChart.dot

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+digraph {
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+  edge [fontsize=14];
+  rankdir=TB;
+
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+  END [shape="circle",width=0.2,label="",style="filled",fillcolor="black",peripheries=2]
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+  "SkippingPrefix.Idle" [label="SkippingPrefix",group="SkippingPrefix"];
+  "WaitForNullKey.Idle" [label="WaitForNullKey",group="WaitForNullKey"];
+  "SkippingVersions.Idle" [label="SkippingVersions",group="SkippingVersions"];
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+  "NotSkippingV0.Processing" [label="NotSkippingV0",group="NotSkipping",width=4];
+  "NotSkippingV1.Processing" [label="NotSkippingV1",group="NotSkipping",width=4];
+  "NotSkippingCommon.Processing" [label="NotSkippingCommon",group="NotSkipping",width=4];
+  "SkippingPrefix.Processing" [label="SkippingPrefix",group="SkippingPrefix"];
+  "WaitForNullKey.Processing" [label="WaitForNullKey",group="WaitForNullKey"];
+  "SkippingVersions.Processing" [label="SkippingVersions",group="SkippingVersions"];
+
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+  START -> "NotSkipping.Idle" [label="[versionIdMarker == undefined]"]
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+  "SkippingPrefix.Idle" -> "SkippingPrefix.Processing" [label="filter(key, value)"]
+  "WaitForNullKey.Idle" -> "WaitForNullKey.Processing" [label="filter(key, value)"]
+  "SkippingVersions.Idle" -> "SkippingVersions.Processing" [label="filter(key, value)"]
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+  "NotSkipping.Processing" -> "NotSkippingV1.Processing" [label="vFormat='v1'"]
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+  "WaitForNullKey.Processing" -> "NotSkipping.Processing" [label="master(key) != keyMarker"]
+  "WaitForNullKey.Processing" -> "SkippingVersions.Processing" [label="master(key) == keyMarker"]
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+  "NotSkippingV1.Processing" -> "NotSkippingCommon.Processing" [label="[always]"]
+  "NotSkippingCommon.Processing" -> END [label="[isListableKey(key, value) and\nKeys == maxKeys]\n-> FILTER_END"]
+  "NotSkippingCommon.Processing" -> "SkippingPrefix.Idle" [label="[isListableKey(key, value) and\nnKeys < maxKeys and\nhasDelimiter(key)]\n/ prefix <- prefixOf(key)\n/ CommonPrefixes.append(prefixOf(key))\n-> FILTER_ACCEPT"]
+  "NotSkippingCommon.Processing" -> "NotSkipping.Idle" [label="[isListableKey(key, value) and\nnKeys < maxKeys and\nnot hasDelimiter(key)]\n/ Contents.append(key, versionId, value)\n-> FILTER_ACCEPT"]
+
+  "SkippingPrefix.Processing" -> "SkippingPrefix.Idle" [label="[key.startsWith(prefix)]\n-> FILTER_SKIP"]
+  "SkippingPrefix.Processing" -> "NotSkipping.Processing" [label="[not key.startsWith(prefix)]"]
+  "SkippingVersions.Processing" -> "NotSkipping.Processing" [label="master(key) !== keyMarker or \nversionId > versionIdMarker"]
+  "SkippingVersions.Processing" -> "SkippingVersions.Idle" [label="master(key) === keyMarker and \nversionId < versionIdMarker\n-> FILTER_SKIP"]
+  "SkippingVersions.Processing" -> "SkippingVersions.Idle" [label="master(key) === keyMarker and \nversionId == versionIdMarker\n-> FILTER_ACCEPT"]
+}

documentation/listingAlgos/pics/delimiterVersionsStateChart.svg

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+<!-- NotSkipping.Idle -->
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+<!-- WaitForNullKey.Idle -->
+<g id="node5" class="node">
+<title>WaitForNullKey.Idle</title>
+<path fill="lightgrey" stroke="black" d="M692.26,-849C692.26,-849 500.26,-849 500.26,-849 494.26,-849 488.26,-843 488.26,-837 488.26,-837 488.26,-825 488.26,-825 488.26,-819 494.26,-813 500.26,-813 500.26,-813 692.26,-813 692.26,-813 698.26,-813 704.26,-819 704.26,-825 704.26,-825 704.26,-837 704.26,-837 704.26,-843 698.26,-849 692.26,-849"/>
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+<!-- NotSkipping.Processing -->
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+</g>
+<!-- NotSkipping.Idle&#45;&gt;NotSkipping.Processing -->
+<g id="edge3" class="edge">
+<title>NotSkipping.Idle&#45;&gt;NotSkipping.Processing</title>
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+<!-- SkippingVersions.Idle&#45;&gt;SkippingVersions.Processing -->
+<g id="edge6" class="edge">
+<title>SkippingVersions.Idle&#45;&gt;SkippingVersions.Processing</title>
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+<text text-anchor="middle" x="1203.26" y="-594.8" font-family="Times,serif" font-size="14.00">filter(key, value)</text>
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+<title>NotSkippingV0.Processing</title>
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+<text text-anchor="middle" x="304.26" y="-389.2" font-family="Times,serif" font-size="16.00">NotSkippingV0</text>
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+<!-- NotSkipping.Processing&#45;&gt;NotSkippingV0.Processing -->
+<g id="edge7" class="edge">
+<title>NotSkipping.Processing&#45;&gt;NotSkippingV0.Processing</title>
+<path fill="none" stroke="black" d="M573.96,-521.95C558.07,-516.64 540.84,-510.46 525.26,-504 460.22,-477.02 387.62,-439.36 343.97,-415.84"/>
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+<!-- NotSkipping.Processing&#45;&gt;NotSkippingV1.Processing -->
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file/kinetic/Kinetic.js.html

@@ -1,741 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-  <meta charset="utf-8">
-  <base data-ice="baseUrl" href="../../">
-  <title data-ice="title">kinetic/Kinetic.js | API Document</title>
-  <link type="text/css" rel="stylesheet" href="css/style.css">
-  <link type="text/css" rel="stylesheet" href="css/prettify-tomorrow.css">
-  <script src="script/prettify/prettify.js"></script>
-  
-  
-  <script src="script/manual.js"></script>
-</head>
-<body class="layout-container" data-ice="rootContainer">
-
-<header>
-  <a href="./">Home</a>
-  
-  <a href="identifiers.html">Reference</a>
-  <a href="source.html">Source</a>
-  
-  <a data-ice="repoURL" href="git+https://github.com/scality/IronMan-Arsenal.git">Repository</a>
-  <div class="search-box">
-  <span>
-    <img src="./image/search.png">
-    <span class="search-input-edge"></span><input class="search-input"><span class="search-input-edge"></span>
-  </span>
-    <ul class="search-result"></ul>
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-</header>
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-<nav class="navigation" data-ice="nav"><div>
-  <ul>
-    
-  <li data-ice="doc"><span data-ice="kind" class="kind-class">C</span><span data-ice="name"><span><a href="class/kinetic/Kinetic.js~Kinetic.html">Kinetic</a></span></span></li>
-<li data-ice="doc"><span data-ice="kind" class="kind-variable">V</span><span data-ice="name"><span><a href="variable/index.html#static-variable-kinetic">kinetic</a></span></span></li>
-</ul>
-</div>
-</nav>
-
-<div class="content" data-ice="content"><h1 data-ice="title">kinetic/Kinetic.js</h1>
-<pre class="source-code line-number raw-source-code"><code class="prettyprint linenums" data-ice="content">import protobuf from &apos;protobufjs&apos;;
-import crypto from &apos;crypto&apos;;
-
-const VERSION = 0x46;
-const protoFilePath = __dirname + &apos;/kinetic.proto&apos;;
-const buildName = &apos;com.seagate.kinetic.proto&apos;;
-
-/**
- * Represents the Kinetic Protocol Data Structure.
- * @constructor
- */
-class Kinetic {
-    constructor() {
-        this._version = VERSION;
-        this.logs = {
-            UTILIZATIONS: 0,
-            TEMPERATURES: 1,
-            CAPACITIES: 2,
-            CONFIGURATION: 3,
-            STATISTICS: 4,
-            MESSAGES: 5,
-            LIMITS: 6,
-            DEVICE: 7,
-        };
-        this.op = {
-            PUT: 4,
-            PUT_RESPONSE: 3,
-            GET: 2,
-            GET_RESPONSE: 1,
-            NOOP: 30,
-            NOOP_RESPONSE: 29,
-            DELETE: 6,
-            DELETE_RESPONSE: 5,
-            SET_CLUSTER_VERSION: 22,
-            SETUP_RESPONSE: 21,
-            FLUSH: 32,
-            FLUSH_RESPONSE: 31,
-            GETLOG: 24,
-            GETLOG_RESPONSE: 23,
-        };
-        this.errors = {
-            INVALID_STATUS_CODE: -1,
-            NOT_ATTEMPTED: 0,
-            SUCCESS: 1,
-            HMAC_FAILURE: 2,
-            NOT_AUTHORIZED: 3,
-            VERSION_FAILURE: 4,
-            INTERNAL_ERROR: 5,
-            HEADER_REQUIRED: 6,
-            NOT_FOUND: 7,
-            VERSION_MISMATCH: 8,
-            SERVICE_BUSY: 9,
-            EXPIRED: 10,
-            DATA_ERROR: 11,
-            PERM_DATA_ERROR: 12,
-            REMOTE_CONNECTION_ERROR: 13,
-            NO_SPACE: 14,
-            NO_SUCH_HMAC_ALGORITHM: 15,
-            INVALID_REQUEST: 16,
-            NESTED_OPERATION_ERRORS: 17,
-            DEVICE_LOCKED: 18,
-            DEVICE_ALREADY_UNLOCKED: 19,
-            CONNECTION_TERMINATED: 20,
-            INVALID_BATCH: 21,
-        };
-        this.build = protobuf.loadProtoFile(protoFilePath).build(buildName);
-        return this;
-    }
-
-
-    /**
-     * Slice the buffer with the offset and the limit.
-     * @param {Object} obj - an object buffer with offset and limit.
-     * @returns {Buffer} sliced buffer from the buffer structure with the offset
-     * and the limit.
-     */
-    getSlice(obj) {
-        return obj.buffer.slice(obj.offset, obj.limit);
-    }
-
-    /**
-     * Sets the actual protobuf message for the Kinetic Protocol Data Unit.
-     * @param {Object} pbMessage - the well formated kinetic protobuf structure.
-     * @returns {Kinetic} to allow for a functional style.
-     */
-    setProtobuf(pbMessage) {
-        this._message = pbMessage;
-        return this;
-    }
-
-
-    /**
-     * Sets the chunk for the Kinetic Protocol Data Unit.
-     * @param {Buffer} chunk.
-     * @returns {Kinetic} to allow for a functional style.
-     */
-    setChunk(chunk) {
-        this._chunk = chunk;
-        return this;
-    }
-
-
-    /**
-     * Sets the general protobuf message for the Kinetic Protocol Data Unit.
-     * @param {Object} command - the well formated general kinetic protobuf
-     * structure.
-     * @returns {Kinetic} setting the protobuf message.
-     */
-    setCommand(command) {
-        const message = new this.build.Command(command);
-        return this.setProtobuf(message);
-    }
-
-    /**
-     * Sets the HMAC for the Kinetic Protocol Data Unit integrity.
-     * @param {Buffer} secret - the shared secret.
-     * @returns {Kinetic} to allow for a functional style.
-     */
-    setHMAC() {
-        this._hmac =  crypto.createHmac(&apos;sha1&apos;, &apos;asdfasdf&apos;)
-            .update(this.getProtobuf().toBuffer()).digest();
-        return this;
-    }
-
-
-    /**
-     * Gets the actual version of the kinetic protocol.
-     * @returns {Number} the current version of the kinetic protocol.
-     */
-    getVersion() {
-        return this._version;
-    }
-
-    /**
-     * Gets the actual protobuf message.
-     * @returns {Object} Kinetic protobuf message.
-     */
-    getProtobuf() {
-        return this._message;
-    }
-
-    /**
-     * Gets the actual protobuf message size.
-     * @returns {Number} Size of the kinetic protobuf message.
-     */
-    getProtobufSize() {
-        return this.getProtobuf().calculate();
-    }
-
-    /**
-     * Gets the actual chunk.
-     * @returns {Buffer} Chunk.
-     */
-    getChunk() {
-        return this._chunk;
-    }
-
-    /**
-     * Gets the actual chunk size.
-     * @returns {Number} Chunk size.
-     */
-    getChunkSize() {
-        return this._chunk.length;
-    }
-
-    /**
-     * Gets the general build template.
-     * @returns {Object} General kinetic protobuf structure.
-     */
-    getCommand() {
-        return this.build.Command;
-    }
-
-    /**
-     * Gets the actual HMAC.
-     * @returns {Buffer} HMAC.
-     */
-    getHMAC() {
-        return this._hmac;
-    }
-
-    /**
-     * Gets the actual request messageType.
-     * @returns {Number} The code number of the request.
-     */
-    getMessageType() {
-        return this.getProtobuf().header.messageType;
-    }
-
-    /**
-     * Gets the actual key.
-     * @returns {Buffer} Key.
-     */
-    getKey() {
-        return this.getSlice(this.getProtobuf().body.keyValue.key);
-    }
-
-    /**
-     * Gets the version of the data unit in the database.
-     * @returns {Buffer} Version of the data unit in the database.
-     */
-    getDbVersion() {
-        return this.getSlice(this.getProtobuf().body.keyValue.dbVersion);
-    }
-
-    /**
-     * Gets the new version of the data unit.
-     * @returns {Buffer} New version of the data unit.
-     */
-    getNewVersion() {
-        return this.getSlice(this.getProtobuf().body.keyValue.newVersion);
-    }
-
-    /**
-     * Gets the detailed error message.
-     * @returns {Buffer} Detailed error message.
-     */
-    getErrorMessage() {
-        return this.getSlice(this.getProtobuf().status.detailedMessage);
-    }
-
-    /**
-     * Gets the logs message.
-     * @returns {Buffer} Logs message.
-     */
-    getGetLogMessage() {
-        return this.getSlice(this.getProtobuf().body.getLog.messages);
-    }
-
-    /**
-     * Gets the operartion name with it code.
-     * @param {Number} opCode - the operation code.
-     * @returns {String} operation name.
-     */
-    getOp(opCode) {
-        return this.getKeyByValue(this.op, opCode);
-    }
-
-    /**
-     * Gets the error name with it code.
-     * @param {Number} errorCode - the error code.
-     * @returns {String} error name.
-     */
-    getError(errorCode) {
-        return this.getKeyByValue(this.errors, errorCode);
-    }
-
-    /**
-     * Gets the log type name with it code.
-     * @param {Number} logCode - the log type code.
-     * @returns {String} log type name.
-     */
-    getLogType(logCode) {
-        return this.getKeyByValue(this.logs, logCode);
-    }
-
-    /**
-     * Gets the key of an object with it value.
-     * @param {Object} object - the corresponding object.
-     * @param {value} value - the corresponding value.
-     * @returns {Buffer} object key.
-     */
-    getKeyByValue(object, value) {
-        return Object.keys(object).find(key =&gt; object[key] === value);
-    }
-
-    /**
-     * Compare two buffers.
-     * @param {Buffer} buf0/buf1 - the buffers to compare.
-     * @returns {Boolean} false if it&apos;s different true if not.
-     */
-    diff(buf0, buf1) {
-        if (buf0.length !== buf1.length) {
-            return false;
-        }
-        for (let i = 0; i &lt;= buf0.length; i++) {
-            if (buf0[i] !== buf1[i])
-                return false;
-        }
-        return true;
-    }
-
-    /**
-     * Test the HMAC integrity between the actual instance and the given HMAC.
-     * @param {Buffer} hmac - the non instance hmac to compare.
-     * @returns {Boolean} true if the HMACs are the same.
-     * @returns an error if they are different.
-     */
-    hmacIntegrity(hmac) {
-        if (hmac === undefined || this.getHMAC() === undefined)
-            return this.errors.HMAC_FAILURE;
-        if (this.diff(hmac, this.getHMAC()) === false)
-            return this.errors.HMAC_FAILURE;
-        return true;
-    }
-
-    /**
-     * Getting logs and stats request following the kinetic protocol.
-     * @param {number} incrementTCP - monotonically increasing number for each
-     * request in a TCP connection.
-     * @param {Array} types - array filled by logs types needed.
-     * @param {number} clusterVersion - version of the cluster
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    getLog(incrementTCP, types, clusterVersion) {
-        const identity = (new Date).getTime();
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;GETLOG&quot;,
-                &quot;connectionID&quot;: identity,
-                &quot;sequence&quot;: incrementTCP,
-                &quot;clusterVersion&quot;: clusterVersion,
-            },
-            &quot;body&quot;: {
-                &quot;getLog&quot;: {
-                    &quot;types&quot;: types,
-
-                },
-            },
-        });
-    }
-
-    /**
-     * Getting logs and stats response following the kinetic protocol.
-     * @param {String or number} response - response code (SUCCESS, FAIL)
-     * @param {String or Buffer} errorMessage - detailed error message.
-     * @param {object} responseLogs - object filled by logs needed.
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    getLogResponse(response, errorMessage, responseLogs) {
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;ackSequence&quot;: this.getProtobuf().header.sequence,
-                &quot;messageType&quot;: &quot;GETLOG_RESPONSE&quot;,
-            },
-            &quot;body&quot;: {
-                &quot;getLog&quot;: responseLogs,
-            },
-            &quot;status&quot;: {
-                &quot;code&quot;: response,
-                &quot;detailedMessage&quot;: errorMessage,
-            },
-        });
-    }
-
-    /**
-     * Flush all data request following the kinetic protocol.
-     * @param {number} incrementTCP - monotonically increasing number for each
-     * request in a TCP connection.
-     * @param {number} clusterVersion - version of the cluster
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    flush(incrementTCP, clusterVersion) {
-        const identity = (new Date).getTime();
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;FLUSHALLDATA&quot;,
-                &quot;connectionID&quot;: identity,
-                &quot;sequence&quot;: incrementTCP,
-                &quot;clusterVersion&quot;: clusterVersion,
-            },
-            &quot;body&quot;: { },
-        });
-    }
-
-    /**
-     * Flush all data response following the kinetic protocol.
-     * @param {String or number} response - response code (SUCCESS, FAIL)
-     * @param {String or Buffer} errorMessage - detailed error message.
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    flushResponse(response, errorMessage) {
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;FLUSHALLDATA_RESPONSE&quot;,
-                &quot;ackSequence&quot;: this.getProtobuf().header.sequence,
-            },
-            &quot;status&quot;: {
-                &quot;code&quot;: response,
-                &quot;detailedMessage&quot;: errorMessage,
-            },
-        });
-    }
-
-    /**
-     * set clusterVersion request following the kinetic protocol.
-     * @param {number} incrementTCP - monotonically increasing number for each
-     * request in a TCP connection.
-     * @param {number} clusterVersion - The version number of this cluster
-     * definition
-     * @param {number} oldClusterVersion - The old version number of this
-     * cluster definition
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    setClusterVersion(incrementTCP, clusterVersion, oldClusterVersion) {
-        const identity = (new Date).getTime();
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;SETUP&quot;,
-                &quot;connectionID&quot;: identity,
-                &quot;sequence&quot;: incrementTCP,
-                &quot;clusterVersion&quot;: oldClusterVersion,
-            },
-            &quot;body&quot;: {
-                &quot;setup&quot;: {
-                    &quot;newClusterVersion&quot;: clusterVersion,
-                },
-            },
-        });
-    }
-
-    /**
-     * Setup response request following the kinetic protocol.
-     * @param {String or number} response - response code (SUCCESS, FAIL)
-     * @param {String or Buffer} errorMessage - detailed error message.
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    setupResponse(response, errorMessage) {
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;SETUP_RESPONSE&quot;,
-                &quot;ackSequence&quot;: this.getProtobuf().header.sequence,
-            },
-            &quot;status&quot;: {
-                &quot;code&quot;: response,
-                &quot;detailedMessage&quot;: errorMessage,
-            },
-        });
-    }
-
-    /**
-     * NOOP request following the kinetic protocol.
-     * @param {number} incrementTCP - monotonically increasing number for each
-     * request in a TCP connection
-     * @param {number} clusterVersion - The version number of this cluster
-     * definition
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    noOp(incrementTCP, clusterVersion) {
-        const identity = (new Date).getTime();
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;NOOP&quot;,
-                &quot;connectionID&quot;: identity,
-                &quot;sequence&quot;: incrementTCP,
-                &quot;clusterVersion&quot;: clusterVersion,
-            },
-        });
-    }
-
-    /**
-     * Response for the NOOP request following the kinetic protocol.
-     * @param {String or number} response - response code (SUCCESS, FAIL)
-     * @param {String or Buffer} errorMessage - detailed error message.
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    noOpResponse(response, errorMessage) {
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;NOOP_RESPONSE&quot;,
-                &quot;ackSequence&quot;: this.getProtobuf().header.sequence,
-            },
-            &quot;status&quot;: {
-                &quot;code&quot;: response,
-                &quot;detailedMessage&quot;: errorMessage,
-            },
-        });
-    }
-
-    /**
-     * PUT request following the kinetic protocol.
-     * @param {String or Buffer} key - key of the item to put.
-     * @param {number} incrementTCP - monotonically increasing number for each
-     * request in a TCP connection
-     * @param {String or Buffer} dbVersion - version of the item in the
-     * database.
-     * @param {String or Buffer} newVersion - new version of the item to put.
-     * @param {number} clusterVersion - The version number of this cluster
-     * definition
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    put(key, incrementTCP, dbVersion, newVersion, clusterVersion) {
-        const identity = (new Date).getTime();
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;PUT&quot;,
-                &quot;connectionID&quot;: identity,
-                &quot;sequence&quot;: incrementTCP,
-                &quot;clusterVersion&quot;: clusterVersion,
-            },
-            &quot;body&quot;: {
-                &quot;keyValue&quot;: {
-                    &quot;key&quot;: key,
-                    &quot;newVersion&quot;: newVersion,
-                    &quot;dbVersion&quot;: dbVersion,
-                },
-            },
-        });
-    }
-
-    /**
-     * Response for the PUT request following the kinetic protocol.
-     * @param {String or number} response - response code (SUCCESS, FAIL)
-     * @param {String or Buffer} errorMessage - detailed error message.
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    putResponse(response, errorMessage) {
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;PUT_RESPONSE&quot;,
-                &quot;ackSequence&quot;: this.getProtobuf().header.sequence,
-            },
-            &quot;body&quot;: {
-                &quot;keyValue&quot;: { },
-            },
-            &quot;status&quot;: {
-                &quot;code&quot;: response,
-                &quot;detailedMessage&quot;: errorMessage,
-            },
-        });
-    }
-
-    /**
-     * GET request following the kinetic protocol.
-     * @param {String or Buffer} key - key of the item to put.
-     * @param {number} incrementTCP - monotonically increasing number for each
-     * request in a TCP connection
-     * @param {number} clusterVersion - The version number of this cluster
-     * definition
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    get(key, incrementTCP, clusterVersion) {
-        const identity = (new Date).getTime();
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;GET&quot;,
-                &quot;connectionID&quot;: identity,
-                &quot;sequence&quot;: incrementTCP,
-                &quot;clusterVersion&quot;: clusterVersion,
-            },
-            &quot;body&quot;: {
-                &quot;keyValue&quot;: {
-                    &quot;key&quot;: key,
-                },
-            },
-        });
-    }
-
-    /**
-     * Response for the GET request following the kinetic protocol.
-     * @param {String or number} response - response code (SUCCESS, FAIL)
-     * @param {String or Buffer} errorMessage - Detailed error message.
-     * @param {String or Buffer} dbVersion - The version of the item in the
-     * database.
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    getResponse(response, errorMessage, dbVersion) {
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;GET_RESPONSE&quot;,
-                &quot;ackSequence&quot;: this.getProtobuf().header.sequence,
-            },
-            &quot;body&quot;: {
-                &quot;keyValue&quot;: {
-                    &quot;key&quot;: this.getProtobuf().body.keyValue.key,
-                    &quot;dbVersion&quot;: dbVersion,
-                },
-            },
-            &quot;status&quot;: {
-                &quot;code&quot;: response,
-                &quot;detailedMessage&quot;: errorMessage,
-            },
-        });
-    }
-
-    /**
-     * DELETE request following the kinetic protocol.
-     * @param {String or Buffer} key - key of the item to put.
-     * @param {number} incrementTCP - monotonically increasing number for each
-     * request in a TCP connection
-     * @param {number} clusterVersion - The version number of this cluster
-     * definition
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    delete(key, incrementTCP, clusterVersion) {
-        const identity = (new Date).getTime();
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;DELETE&quot;,
-                &quot;connectionID&quot;: identity,
-                &quot;sequence&quot;: incrementTCP,
-                &quot;clusterVersion&quot;: clusterVersion,
-            },
-            &quot;body&quot;: {
-                &quot;keyValue&quot;: {
-                    &quot;key&quot;: key,
-                },
-            },
-        });
-    }
-
-    /**
-     * Response for the DELETE request following the kinetic protocol.
-     * @param {String or number} response - response code (SUCCESS, FAIL)
-     * @param {String or Buffer} errorMessage - Detailed error message.
-     * @returns {Kinetic} this - message structure following the kinetic
-     * protocol
-     */
-    deleteResponse(response, errorMessage) {
-        return this.setCommand({
-            &quot;header&quot;: {
-                &quot;messageType&quot;: &quot;DELETE_RESPONSE&quot;,
-                &quot;ackSequence&quot;: this.getProtobuf().header.sequence,
-            },
-            &quot;body&quot;: {
-                &quot;keyValue&quot;: { },
-            },
-            &quot;status&quot;: {
-                &quot;code&quot;: response,
-                &quot;detailedMessage&quot;: errorMessage,
-            },
-        });
-    }
-
-    /**
-     * Sends data following Kinetic protocol.
-     * @param {Socket} sock - Socket to send data through.
-     */
-    send(sock) {
-        const buf = new Buffer(9);
-
-        buf.writeInt8(this.getVersion(), 0);
-
-        // BE stands for Big Endian
-        buf.writeInt32BE(this.getProtobufSize(), 1);
-        buf.writeInt32BE(this.getChunkSize(), 5);
-
-        sock.write(Buffer.concat(
-                [buf, this.getProtobuf().toBuffer(), this.getChunk()]
-            ));
-    }
-
-    /**
-     * Creates the Kinetic Protocol Data Structure from a buffer.
-     * @param {Buffer} data - The data received by the socket.
-     */
-    parse(data) {
-        const version = data.readInt8(0);
-        const pbMsgLen = data.readInt32BE(1);
-        const chunkLen = data.readInt32BE(5);
-
-        if (version !== this.getVersion()) {
-            return this.errors.VERSION_FAILURE;
-        }
-        try {
-            this.setProtobuf(
-                this.getCommand().decode(data.slice(9, pbMsgLen + 9))
-            );
-            this.setChunk(data.slice(pbMsgLen + 9, chunkLen + pbMsgLen + 9));
-        } catch (e) {
-            return e;
-        }
-        if (this.getChunkSize() !== chunkLen) {
-            return this.errors.DATA_ERROR;
-        }
-        return this.errors.SUCCESS;
-    }
-}
-
-export default Kinetic;
-</code></pre>
-
-</div>
-
-<footer class="footer">
-  Generated by <a href="https://esdoc.org">ESDoc<span data-ice="esdocVersion">(0.4.1)</span></a>
-</footer>
-
-<script src="script/search_index.js"></script>
-<script src="script/search.js"></script>
-<script src="script/pretty-print.js"></script>
-<script src="script/inherited-summary.js"></script>
-<script src="script/test-summary.js"></script>
-<script src="script/inner-link.js"></script>
-<script src="script/patch-for-local.js"></script>
-</body>
-</html>

greenkeeper.json

@@ -0,0 +1,28 @@
+{
+  "groups": {
+    "default": {
+      "packages": [
+        "lib/executables/pensieveCreds/package.json",
+        "package.json"
+      ]
+    }
+  },
+  "branchPrefix": "improvement/greenkeeper.io/",
+  "commitMessages": {
+    "initialBadge": "docs(readme): add Greenkeeper badge",
+    "initialDependencies": "chore(package): update dependencies",
+    "initialBranches": "chore(bert-e): whitelist greenkeeper branches",
+    "dependencyUpdate": "fix(package): update ${dependency} to version ${version}",
+    "devDependencyUpdate": "chore(package): update ${dependency} to version ${version}",
+    "dependencyPin": "fix: pin ${dependency} to ${oldVersionResolved}",
+    "devDependencyPin": "chore: pin ${dependency} to ${oldVersionResolved}",
+    "closes": "\n\nCloses #${number}"
+  },
+  "ignore": [
+    "ajv",
+    "eslint",
+    "eslint-plugin-react",
+    "eslint-config-airbnb",
+    "eslint-config-scality"
+  ]
+}

identifiers.html

@@ -1,125 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-  <meta charset="utf-8">
-  <base data-ice="baseUrl">
-  <title data-ice="title">Index | API Document</title>
-  <link type="text/css" rel="stylesheet" href="css/style.css">
-  <link type="text/css" rel="stylesheet" href="css/prettify-tomorrow.css">
-  <script src="script/prettify/prettify.js"></script>
-  
-  
-  <script src="script/manual.js"></script>
-</head>
-<body class="layout-container" data-ice="rootContainer">
-
-<header>
-  <a href="./">Home</a>
-  
-  <a href="identifiers.html">Reference</a>
-  <a href="source.html">Source</a>
-  
-  <a data-ice="repoURL" href="git+https://github.com/scality/IronMan-Arsenal.git">Repository</a>
-  <div class="search-box">
-  <span>
-    <img src="./image/search.png">
-    <span class="search-input-edge"></span><input class="search-input"><span class="search-input-edge"></span>
-  </span>
-    <ul class="search-result"></ul>
-  </div>
-</header>
-
-<nav class="navigation" data-ice="nav"><div>
-  <ul>
-    
-  <li data-ice="doc"><span data-ice="kind" class="kind-class">C</span><span data-ice="name"><span><a href="class/kinetic/Kinetic.js~Kinetic.html">Kinetic</a></span></span></li>
-<li data-ice="doc"><span data-ice="kind" class="kind-variable">V</span><span data-ice="name"><span><a href="variable/index.html#static-variable-kinetic">kinetic</a></span></span></li>
-</ul>
-</div>
-</nav>
-
-<div class="content" data-ice="content"><h1>References</h1>
-<div data-ice="classSummary"><h2 id="class">Class Summary</h2><table class="summary" data-ice="summary">
-  <thead><tr><td data-ice="title" colspan="3">Static Public Class Summary</td></tr></thead>
-  <tbody>
-  
-  <tr data-ice="target">
-    <td>
-      <span class="access" data-ice="access">public</span>
-      
-      
-      
-      <span class="override" data-ice="override"></span>
-    </td>
-    <td>
-      <div>
-        <p>
-           <span data-ice="name"><span><a href="class/kinetic/Kinetic.js~Kinetic.html">Kinetic</a></span></span>
-        </p>
-      </div>
-      <div>
-        
-        
-        <div data-ice="description"><p>Represents the Kinetic Protocol Data Structure.</p>
-</div>
-      </div>
-    </td>
-    <td>
-      
-      
-    </td>
-  </tr>
-</tbody>
-</table>
-</div>
-
-
-<div data-ice="variableSummary"><h2 id="variable">Variable Summary</h2><table class="summary" data-ice="summary">
-  <thead><tr><td data-ice="title" colspan="3">Static Public Variable Summary</td></tr></thead>
-  <tbody>
-  
-  <tr data-ice="target">
-    <td>
-      <span class="access" data-ice="access">public</span>
-      
-      
-      
-      <span class="override" data-ice="override"></span>
-    </td>
-    <td>
-      <div>
-        <p>
-           <span data-ice="name"><span><a href="variable/index.html#static-variable-kinetic">kinetic</a></span></span><span data-ice="signature">: <span><a href="class/kinetic/Kinetic.js~Kinetic.html">Kinetic</a></span></span>
-        </p>
-      </div>
-      <div>
-        
-        
-        
-      </div>
-    </td>
-    <td>
-      
-      
-    </td>
-  </tr>
-</tbody>
-</table>
-</div>
-
-
-</div>
-
-<footer class="footer">
-  Generated by <a href="https://esdoc.org">ESDoc<span data-ice="esdocVersion">(0.4.1)</span></a>
-</footer>
-
-<script src="script/search_index.js"></script>
-<script src="script/search.js"></script>
-<script src="script/pretty-print.js"></script>
-<script src="script/inherited-summary.js"></script>
-<script src="script/test-summary.js"></script>
-<script src="script/inner-link.js"></script>
-<script src="script/patch-for-local.js"></script>
-</body>
-</html>

image/badge.svg

@@ -1,17 +0,0 @@
-<svg xmlns="http://www.w3.org/2000/svg" width="102" height="20">
-  <script/>
-  <linearGradient id="a" x2="0" y2="100%">
-    <stop offset="0" stop-color="#bbb" stop-opacity=".1"/>
-    <stop offset="1" stop-opacity=".1"/>
-  </linearGradient>
-  <rect rx="3" width="102" height="20" fill="#555"/>
-  <rect rx="3" x="64" width="38" height="20" fill="@color@"/>
-  <path fill="@color@" d="M64 0h4v20h-4z"/>
-  <rect rx="3" width="102" height="20" fill="url(#a)"/>
-  <g fill="#fff" text-anchor="middle" font-family="DejaVu Sans,Verdana,Geneva,sans-serif" font-size="11">
-    <text x="32" y="15" fill="#010101" fill-opacity=".3">document</text>
-    <text x="32" y="14">document</text>
-    <text x="82.5" y="15" fill="#010101" fill-opacity=".3">@ratio@</text>
-    <text x="82.5" y="14">@ratio@</text>
-  </g>
-</svg>

index.html

@@ -1,63 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-  <meta charset="utf-8">
-  <base data-ice="baseUrl">
-  <title data-ice="title">API Document</title>
-  <link type="text/css" rel="stylesheet" href="css/style.css">
-  <link type="text/css" rel="stylesheet" href="css/prettify-tomorrow.css">
-  <script src="script/prettify/prettify.js"></script>
-  
-  
-  <script src="script/manual.js"></script>
-</head>
-<body class="layout-container" data-ice="rootContainer">
-
-<header>
-  <a href="./">Home</a>
-  
-  <a href="identifiers.html">Reference</a>
-  <a href="source.html">Source</a>
-  
-  <a data-ice="repoURL" href="git+https://github.com/scality/IronMan-Arsenal.git">Repository</a>
-  <div class="search-box">
-  <span>
-    <img src="./image/search.png">
-    <span class="search-input-edge"></span><input class="search-input"><span class="search-input-edge"></span>
-  </span>
-    <ul class="search-result"></ul>
-  </div>
-</header>
-
-<nav class="navigation" data-ice="nav"><div>
-  <ul>
-    
-  <li data-ice="doc"><span data-ice="kind" class="kind-class">C</span><span data-ice="name"><span><a href="class/kinetic/Kinetic.js~Kinetic.html">Kinetic</a></span></span></li>
-<li data-ice="doc"><span data-ice="kind" class="kind-variable">V</span><span data-ice="name"><span><a href="variable/index.html#static-variable-kinetic">kinetic</a></span></span></li>
-</ul>
-</div>
-</nav>
-
-<div class="content" data-ice="content"><div data-ice="index" class="github-markdown"><h1 id="ironman-arsenal">IronMan-Arsenal</h1>
-<p>Common utilities for the IronMan project components</p>
-<p>Within this repository, you will be able to find the shared libraries for the
-multiple components making up the whole Project.</p>
-<h2 id="guidelines">Guidelines</h2>
-<p>Please read our coding and workflow guidelines at
-<a href="https://github.com/scality/IronMan-Guidelines">scality/IronMan-Guidelines</a>.</p>
-</div>
-</div>
-
-<footer class="footer">
-  Generated by <a href="https://esdoc.org">ESDoc<span data-ice="esdocVersion">(0.4.1)</span></a>
-</footer>
-
-<script src="script/search_index.js"></script>
-<script src="script/search.js"></script>
-<script src="script/pretty-print.js"></script>
-<script src="script/inherited-summary.js"></script>
-<script src="script/test-summary.js"></script>
-<script src="script/inner-link.js"></script>
-<script src="script/patch-for-local.js"></script>
-</body>
-</html>

index.ts

@@ -0,0 +1,175 @@
+import * as evaluators from './lib/policyEvaluator/evaluator';
+import evaluatePrincipal from './lib/policyEvaluator/principal';
+import RequestContext, {
+    actionNeedQuotaCheck,
+    actionNeedQuotaCheckCopy,
+    actionWithDataDeletion } from './lib/policyEvaluator/RequestContext';
+import * as requestUtils from './lib/policyEvaluator/requestUtils';
+import * as actionMaps from './lib/policyEvaluator/utils/actionMaps';
+import { validateUserPolicy } from './lib/policy/policyValidator'
+import * as locationConstraints from './lib/patches/locationConstraints';
+import * as userMetadata from './lib/s3middleware/userMetadata';
+import convertToXml from './lib/s3middleware/convertToXml';
+import escapeForXml from './lib/s3middleware/escapeForXml';
+import * as objectLegalHold from './lib/s3middleware/objectLegalHold';
+import * as tagging from './lib/s3middleware/tagging';
+import { checkDateModifiedHeaders } from './lib/s3middleware/validateConditionalHeaders';
+import { validateConditionalHeaders } from './lib/s3middleware/validateConditionalHeaders';
+import MD5Sum from './lib/s3middleware/MD5Sum';
+import NullStream from './lib/s3middleware/nullStream';
+import * as objectUtils from './lib/s3middleware/objectUtils';
+import * as mpuUtils from './lib/s3middleware/azureHelpers/mpuUtils';
+import ResultsCollector from './lib/s3middleware/azureHelpers/ResultsCollector';
+import SubStreamInterface from './lib/s3middleware/azureHelpers/SubStreamInterface';
+import { prepareStream } from './lib/s3middleware/prepareStream';
+import * as processMpuParts from './lib/s3middleware/processMpuParts';
+import * as retention from './lib/s3middleware/objectRetention';
+import * as objectRestore from './lib/s3middleware/objectRestore';
+import * as lifecycleHelpers from './lib/s3middleware/lifecycleHelpers';
+export { default as errors } from './lib/errors';
+export { default as Clustering } from './lib/Clustering';
+export * as ClusterRPC from './lib/clustering/ClusterRPC';
+export * as ipCheck from './lib/ipCheck';
+export * as auth from './lib/auth/auth';
+export * as constants from './lib/constants';
+export * as https from './lib/https';
+export * as metrics from './lib/metrics';
+export * as network from './lib/network';
+export * as s3routes from './lib/s3routes';
+export * as versioning from './lib/versioning';
+export * as stream from './lib/stream';
+export * as jsutil from './lib/jsutil';
+export { default as stringHash } from './lib/stringHash';
+export * as db from './lib/db';
+export * as errorUtils from './lib/errorUtils';
+export { default as shuffle } from './lib/shuffle';
+export * as models from './lib/models';
+
+export const algorithms = {
+    list: require('./lib/algos/list/exportAlgos'),
+    listTools: {
+        DelimiterTools: require('./lib/algos/list/tools'),
+        Skip: require('./lib/algos/list/skip'),
+    },
+    cache: {
+        GapSet: require('./lib/algos/cache/GapSet'),
+        GapCache: require('./lib/algos/cache/GapCache'),
+        LRUCache: require('./lib/algos/cache/LRUCache'),
+    },
+    stream: {
+        MergeStream: require('./lib/algos/stream/MergeStream'),
+    },
+    SortedSet: require('./lib/algos/set/SortedSet'),
+    Heap: require('./lib/algos/heap/Heap'),
+};
+
+export const policies = {
+    evaluators,
+    validateUserPolicy,
+    evaluatePrincipal,
+    RequestContext,
+    requestUtils,
+    actionMaps,
+    actionNeedQuotaCheck,
+    actionWithDataDeletion,
+    actionNeedQuotaCheckCopy,
+};
+
+export const testing = {
+    matrix: require('./lib/testing/matrix.js'),
+};
+
+export const s3middleware = {
+    userMetadata,
+    convertToXml,
+    escapeForXml,
+    objectLegalHold,
+    tagging,
+    checkDateModifiedHeaders,
+    validateConditionalHeaders,
+    MD5Sum,
+    NullStream,
+    objectUtils,
+    azureHelper: {
+        mpuUtils,
+        ResultsCollector,
+        SubStreamInterface,
+    },
+    prepareStream,
+    processMpuParts,
+    retention,
+    objectRestore,
+    lifecycleHelpers,
+};
+
+export const storage = {
+    metadata: {
+        MetadataWrapper: require('./lib/storage/metadata/MetadataWrapper'),
+        bucketclient: {
+            BucketClientInterface:
+            require('./lib/storage/metadata/bucketclient/' +
+                'BucketClientInterface'),
+            LogConsumer:
+            require('./lib/storage/metadata/bucketclient/LogConsumer'),
+        },
+        file: {
+            BucketFileInterface:
+            require('./lib/storage/metadata/file/BucketFileInterface'),
+            MetadataFileServer:
+            require('./lib/storage/metadata/file/MetadataFileServer'),
+            MetadataFileClient:
+            require('./lib/storage/metadata/file/MetadataFileClient'),
+        },
+        inMemory: {
+            metastore:
+            require('./lib/storage/metadata/in_memory/metastore'),
+            metadata: require('./lib/storage/metadata/in_memory/metadata'),
+            bucketUtilities:
+            require('./lib/storage/metadata/in_memory/bucket_utilities'),
+        },
+        mongoclient: {
+            MongoClientInterface:
+            require('./lib/storage/metadata/mongoclient/' +
+                'MongoClientInterface'),
+            LogConsumer:
+            require('./lib/storage/metadata/mongoclient/LogConsumer'),
+        },
+        proxy: {
+            Server: require('./lib/storage/metadata/proxy/Server'),
+        },
+    },
+    data: {
+        DataWrapper: require('./lib/storage/data/DataWrapper'),
+        MultipleBackendGateway:
+        require('./lib/storage/data/MultipleBackendGateway'),
+        parseLC: require('./lib/storage/data/LocationConstraintParser'),
+        file: {
+            DataFileStore:
+            require('./lib/storage/data/file/DataFileStore'),
+            DataFileInterface:
+            require('./lib/storage/data/file/DataFileInterface'),
+        },
+        external: {
+            AwsClient: require('./lib/storage/data/external/AwsClient'),
+            AzureClient: require('./lib/storage/data/external/AzureClient'),
+            GcpClient: require('./lib/storage/data/external/GcpClient'),
+            GCP: require('./lib/storage/data/external/GCP/GcpService'),
+            GcpUtils: require('./lib/storage/data/external/GCP/GcpUtils'),
+            GcpSigner: require('./lib/storage/data/external/GCP/GcpSigner'),
+            PfsClient: require('./lib/storage/data/external/PfsClient'),
+            backendUtils: require('./lib/storage/data/external/utils'),
+        },
+        inMemory: {
+            datastore: require('./lib/storage/data/in_memory/datastore'),
+        },
+    },
+    utils: require('./lib/storage/utils'),
+};
+
+export const pensieve = {
+    credentialUtils: require('./lib/executables/pensieveCreds/utils'),
+};
+
+export const patches = {
+    locationConstraints,
+};

lib/Clustering.ts

@@ -0,0 +1,280 @@
+import cluster, { Worker } from 'cluster';
+import * as werelogs from 'werelogs';
+
+export default class Clustering {
+    _size: number;
+    _shutdownTimeout: number;
+    _logger: werelogs.Logger;
+    _shutdown: boolean;
+    _workers: (Worker | undefined)[];
+    _workersTimeout: (NodeJS.Timeout | undefined)[];
+    _workersStatus: (number | string | undefined)[];
+    _status: number;
+    _exitCb?: (clustering: Clustering, exitSignal?: string) => void;
+    _index?: number;
+
+    /**
+     * Constructor
+     *
+     * @param size Cluster size
+     * @param logger Logger object
+     * @param [shutdownTimeout=5000] Change default shutdown timeout
+     * releasing ressources
+     * @return itself
+     */
+    constructor(size: number, logger: werelogs.Logger, shutdownTimeout?: number) {
+        this._size = size;
+        if (size < 1) {
+            throw new Error('Cluster size must be greater than or equal to 1');
+        }
+        this._shutdownTimeout = shutdownTimeout || 5000;
+        this._logger = logger;
+        this._shutdown = false;
+        this._workers = new Array(size).fill(undefined);
+        this._workersTimeout = new Array(size).fill(undefined);
+        this._workersStatus = new Array(size).fill(undefined);
+        this._status = 0;
+        this._exitCb = undefined; // Exit callback
+        this._index = undefined;
+    }
+
+    /**
+     * Method called after a stop() call
+     *
+     * @private
+     */
+    _afterStop() {
+        // Asuming all workers shutdown gracefully
+        this._status = 0;
+        const size = this._size;
+        for (let i = 0; i < size; ++i) {
+            // If the process return an error code or killed by a signal,
+            // set the status
+            const status = this._workersStatus[i];
+            if (typeof status === 'number') {
+                this._status = status;
+                break;
+            } else if (typeof status === 'string') {
+                this._status = 1;
+                break;
+            }
+        }
+        if (this._exitCb) {
+            return this._exitCb(this);
+        }
+        return process.exit(this.getStatus());
+    }
+
+    /**
+     * Method called when a worker exited
+     *
+     * @param worker - Current worker
+     * @param i - Worker index
+     * @param code - Exit code
+     * @param signal - Exit signal
+     */
+    _workerExited(
+        worker: Worker,
+        i: number,
+        code: number,
+        signal: string,
+    ) {
+        // If the worker:
+        //   - was killed by a signal
+        //   - return an error code
+        //   - or just stopped
+        if (signal) {
+            this._logger.info('Worker killed by signal', {
+                signal,
+                id: i,
+                childPid: worker.process.pid,
+            });
+            this._workersStatus[i] = signal;
+        } else if (code !== 0) {
+            this._logger.error('Worker exit with code', {
+                code,
+                id: i,
+                childPid: worker.process.pid,
+            });
+            this._workersStatus[i] = code;
+        } else {
+            this._logger.info('Worker shutdown gracefully', {
+                id: i,
+                childPid: worker.process.pid,
+            });
+            this._workersStatus[i] = undefined;
+        }
+        this._workers[i] = undefined;
+        const timeout = this._workersTimeout[i];
+        if (timeout) {
+            clearTimeout(timeout);
+            this._workersTimeout[i] = undefined;
+        }
+        // If we don't trigger the stop method, the watchdog
+        // will autorestart the worker
+        if (this._shutdown === false) {
+            return process.nextTick(() => this.startWorker(i));
+        }
+        // Check if an worker is still running
+        if (!this._workers.every(cur => cur === undefined)) {
+            return undefined;
+        }
+        return this._afterStop();
+    }
+
+    /**
+     * Method to start a worker
+     *
+     * @param i Index of the starting worker
+     */
+    startWorker(i: number) {
+        if (!cluster.isPrimary) {
+            return;
+        }
+        // Fork a new worker
+        this._workers[i] = cluster.fork();
+        // Listen for message from the worker
+        this._workers[i]!.on('message', msg => {
+            // If the worker is ready, send him his id
+            if (msg === 'ready') {
+                this._workers[i]!.send({ msg: 'setup', id: i });
+            }
+        });
+        this._workers[i]!.on('exit', (code, signal) =>
+            this._workerExited(this._workers[i]!, i, code, signal));
+        // Trigger when the worker was started
+        this._workers[i]!.on('online', () => {
+            this._logger.info('Worker started', {
+                id: i,
+                childPid: this._workers[i]!.process.pid,
+            });
+        });
+    }
+
+    /**
+     * Method to put handler on cluster exit
+     *
+     * @param cb - Callback(Clustering, [exitSignal])
+     * @return Itself
+     */
+    onExit(cb: (clustering: Clustering, exitSignal?: string) => void) {
+        this._exitCb = cb;
+        return this;
+    }
+
+    /**
+     * Method to start the cluster (if master) or to start the callback
+     * (worker)
+     *
+     * @param cb - Callback to run the worker
+     * @return itself
+     */
+    start(cb: (clustering: Clustering) => void) {
+        process.on('SIGINT', () => this.stop('SIGINT'));
+        process.on('SIGHUP', () => this.stop('SIGHUP'));
+        process.on('SIGQUIT', () => this.stop('SIGQUIT'));
+        process.on('SIGTERM', () => this.stop('SIGTERM'));
+        process.on('SIGPIPE', () => {});
+        process.on('exit', (code?: number, signal?: string) => {
+            if (this._exitCb) {
+                this._status = code || 0;
+                return this._exitCb(this, signal);
+            }
+            return process.exit(code || 0);
+        });
+        process.on('uncaughtException', (err: Error) => {
+            this._logger.fatal('caught error', {
+                error: err.message,
+                stack: err.stack?.split('\n')?.map(str => str.trim()),
+            });
+            process.exit(1);
+        });
+        if (!cluster.isPrimary) {
+            // Waiting for message from master to
+            // know the id of the slave cluster
+            process.on('message', (msg: any) => {
+                if (msg.msg === 'setup') {
+                    this._index = msg.id;
+                    cb(this);
+                }
+            });
+            // Send message to the master, to let him know
+            // the worker has started
+            process.send?.('ready');
+        } else {
+            for (let i = 0; i < this._size; ++i) {
+                this.startWorker(i);
+            }
+        }
+        return this;
+    }
+
+    /**
+     * Method to get workers
+     *
+     * @return Workers
+     */
+    getWorkers() {
+        return this._workers;
+    }
+
+    /**
+     * Method to get the status of the cluster
+     *
+     * @return Status code
+     */
+    getStatus() {
+        return this._status;
+    }
+
+    /**
+     * Method to return if it's the master process
+     *
+     * @return - True if master, false otherwise
+     */
+    isMaster() {
+        return this._index === undefined;
+    }
+
+    /**
+     * Method to get index of the worker
+     *
+     * @return Worker index, undefined if it's master
+     */
+    getIndex() {
+        return this._index;
+    }
+
+    /**
+     * Method to stop the cluster
+     *
+     * @param signal - Set internally when processes killed by signal
+     */
+    stop(signal?: string) {
+        if (!cluster.isPrimary) {
+            if (this._exitCb) {
+                return this._exitCb(this, signal);
+            }
+            return process.exit(0);
+        }
+        this._shutdown = true;
+        return this._workers.forEach((worker, i) => {
+            if (!worker) {
+                return undefined;
+            }
+            this._workersTimeout[i] = setTimeout(() => {
+                // Kill the worker if the sigterm was ignored or take too long
+                if (worker.process.pid) {
+                  process.kill(worker.process.pid, 'SIGKILL');
+                }
+            }, this._shutdownTimeout);
+            // Send sigterm to the process, allowing to release ressources
+            // and save some states
+            if (worker.process.pid) {
+              return process.kill(worker.process.pid, 'SIGTERM');
+            } else {
+              return true;
+            }
+        });
+    }
+}

lib/algos/cache/GapCache.ts

@@ -0,0 +1,363 @@
+import { OrderedSet } from '@js-sdsl/ordered-set';
+import {
+    default as GapSet,
+    GapSetEntry,
+} from './GapSet';
+
+// the API is similar but is not strictly a superset of GapSetInterface
+// so we don't extend from it
+export interface GapCacheInterface {
+    exposureDelayMs: number;
+    maxGapWeight: number;
+    size: number;
+
+    setGap: (firstKey: string, lastKey: string, weight: number) => void;
+    removeOverlappingGaps: (overlappingKeys: string[]) => number;
+    lookupGap: (minKey: string, maxKey?: string) => Promise<GapSetEntry | null>;
+    [Symbol.iterator]: () => Iterator<GapSetEntry>;
+    toArray: () => GapSetEntry[];
+};
+
+class GapCacheUpdateSet {
+    newGaps: GapSet;
+    updatedKeys: OrderedSet<string>;
+
+    constructor(maxGapWeight: number) {
+        this.newGaps = new GapSet(maxGapWeight);
+        this.updatedKeys = new OrderedSet();
+    }
+
+    addUpdateBatch(updatedKeys: OrderedSet<string>): void {
+        this.updatedKeys.union(updatedKeys);
+    }
+};
+
+/**
+ * Cache of listing "gaps" i.e. ranges of keys that can be skipped
+ * over during listing (because they only contain delete markers as
+ * latest versions).
+ *
+ * Typically, a single GapCache instance would be attached to a raft session.
+ *
+ * The API usage is as follows:
+ *
+ * - Initialize a GapCache instance by calling start() (this starts an internal timer)
+ *
+ * - Insert a gap or update an existing one via setGap()
+ *
+ * - Lookup existing gaps via lookupGap()
+ *
+ * - Invalidate gaps that overlap a specific set of keys via removeOverlappingGaps()
+ *
+ * - Shut down a GapCache instance by calling stop() (this stops the internal timer)
+ *
+ * Gaps inserted via setGap() are not exposed immediately to lookupGap(), but only:
+ *
+ * - after a certain delay always larger than 'exposureDelayMs' and usually shorter
+ *   than twice this value (but might be slightly longer in rare cases)
+ *
+ * - and only if they haven't been invalidated by a recent call to removeOverlappingGaps()
+ *
+ * This ensures atomicity between gap creation and invalidation from updates under
+ * the condition that a gap is created from first key to last key within the time defined
+ * by 'exposureDelayMs'.
+ *
+ * The implementation is based on two extra temporary "update sets" on top of the main
+ * exposed gap set, one called "staging" and the other "frozen", each containing a
+ * temporary updated gap set and a list of updated keys to invalidate gaps with (coming
+ * from calls to removeOverlappingGaps()). Every "exposureDelayMs" milliseconds, the frozen
+ * gaps are invalidated by all key updates coming from either of the "staging" or "frozen"
+ * update set, then merged into the exposed gaps set, after which the staging updates become
+ * the frozen updates and won't receive any new gap until the next cycle.
+ */
+export default class GapCache implements GapCacheInterface {
+    _exposureDelayMs: number;
+    maxGaps: number;
+
+    _stagingUpdates: GapCacheUpdateSet;
+    _frozenUpdates: GapCacheUpdateSet;
+    _exposedGaps: GapSet;
+    _exposeFrozenInterval: NodeJS.Timeout | null;
+
+    /**
+     * @constructor
+     *
+     * @param {number} exposureDelayMs - minimum delay between
+     * insertion of a gap via setGap() and its exposure via
+     * lookupGap()
+     * @param {number} maxGaps - maximum number of cached gaps, after
+     * which no new gap can be added by setGap(). (Note: a future
+     * improvement could replace this by an eviction strategy)
+     * @param {number} maxGapWeight - maximum "weight" of individual
+     * cached gaps, which is also the granularity for
+     * invalidation. Individual gaps can be chained together,
+     * which lookupGap() transparently consolidates in the response
+     * into a single large gap.
+     */
+    constructor(exposureDelayMs: number, maxGaps: number, maxGapWeight: number) {
+        this._exposureDelayMs = exposureDelayMs;
+        this.maxGaps = maxGaps;
+
+        this._stagingUpdates = new GapCacheUpdateSet(maxGapWeight);
+        this._frozenUpdates = new GapCacheUpdateSet(maxGapWeight);
+        this._exposedGaps = new GapSet(maxGapWeight);
+        this._exposeFrozenInterval = null;
+    }
+
+    /**
+     * Create a GapCache from an array of exposed gap entries (used in tests)
+     *
+     * @return {GapCache} - a new GapCache instance
+     */
+    static createFromArray(
+        gaps: GapSetEntry[],
+        exposureDelayMs: number,
+        maxGaps: number,
+        maxGapWeight: number
+    ): GapCache {
+        const gapCache = new GapCache(exposureDelayMs, maxGaps, maxGapWeight);
+        gapCache._exposedGaps = GapSet.createFromArray(gaps, maxGapWeight)
+        return gapCache;
+    }
+
+    /**
+     * Internal helper to remove gaps in the staging and frozen sets
+     * overlapping with previously updated keys, right before the
+     * frozen gaps get exposed.
+     *
+     * @return {undefined}
+     */
+    _removeOverlappingGapsBeforeExpose(): void {
+        for (const { updatedKeys } of [this._stagingUpdates, this._frozenUpdates]) {
+            if (updatedKeys.size() === 0) {
+                continue;
+            }
+            for (const { newGaps } of [this._stagingUpdates, this._frozenUpdates]) {
+                if (newGaps.size === 0) {
+                    continue;
+                }
+                newGaps.removeOverlappingGaps(updatedKeys);
+            }
+        }
+    }
+
+    /**
+     * This function is the core mechanism that updates the exposed gaps in the
+     * cache. It is called on a regular interval defined by 'exposureDelayMs'.
+     *
+     * It does the following in order:
+     *
+     * - remove gaps from the frozen set that overlap with any key present in a
+     *   batch passed to removeOverlappingGaps() since the last two triggers of
+     *   _exposeFrozen()
+     *
+     * - merge the remaining gaps from the frozen set to the exposed set, which
+     *   makes them visible from calls to lookupGap()
+     *
+     * - rotate by freezing the currently staging updates and initiating a new
+     *   staging updates set
+     *
+     * @return {undefined}
+     */
+    _exposeFrozen(): void {
+        this._removeOverlappingGapsBeforeExpose();
+        for (const gap of this._frozenUpdates.newGaps) {
+            // Use a trivial strategy to keep the cache size within
+            // limits: refuse to add new gaps when the size is above
+            // the 'maxGaps' threshold. We solely rely on
+            // removeOverlappingGaps() to make space for new gaps.
+            if (this._exposedGaps.size < this.maxGaps) {
+                this._exposedGaps.setGap(gap.firstKey, gap.lastKey, gap.weight);
+            }
+        }
+        this._frozenUpdates = this._stagingUpdates;
+        this._stagingUpdates = new GapCacheUpdateSet(this.maxGapWeight);
+    }
+
+    /**
+     * Start the internal GapCache timer
+     *
+     * @return {undefined}
+     */
+    start(): void {
+        if (this._exposeFrozenInterval) {
+            return;
+        }
+        this._exposeFrozenInterval = setInterval(
+            () => this._exposeFrozen(),
+            this._exposureDelayMs);
+    }
+
+    /**
+     * Stop the internal GapCache timer
+     *
+     * @return {undefined}
+     */
+    stop(): void {
+        if (this._exposeFrozenInterval) {
+            clearInterval(this._exposeFrozenInterval);
+            this._exposeFrozenInterval = null;
+        }
+    }
+
+    /**
+     * Record a gap between two keys, associated with a weight to
+     * limit individual gap's spanning ranges in the cache, for a more
+     * granular invalidation.
+     *
+     * The function handles splitting and merging existing gaps to
+     * maintain an optimal weight of cache entries.
+     *
+     * NOTE 1: the caller must ensure that the full length of the gap
+     * between 'firstKey' and 'lastKey' has been built from a listing
+     * snapshot that is more recent than 'exposureDelayMs' milliseconds,
+     * in order to guarantee that the exposed gap will be fully
+     * covered (and potentially invalidated) from recent calls to
+     * removeOverlappingGaps().
+     *
+     * NOTE 2: a usual pattern when building a large gap from multiple
+     * calls to setGap() is to start the next gap from 'lastKey',
+     * which will be passed as 'firstKey' in the next call, so that
+     * gaps can be chained together and consolidated by lookupGap().
+     *
+     * @param {string} firstKey - first key of the gap
+     * @param {string} lastKey - last key of the gap, must be greater
+     * or equal than 'firstKey'
+     * @param {number} weight - total weight between 'firstKey' and 'lastKey'
+     * @return {undefined}
+     */
+    setGap(firstKey: string, lastKey: string, weight: number): void {
+        this._stagingUpdates.newGaps.setGap(firstKey, lastKey, weight);
+    }
+
+    /**
+     * Remove gaps that overlap with a given set of keys. Used to
+     * invalidate gaps when keys are inserted or deleted.
+     *
+     * @param {OrderedSet<string> | string[]} overlappingKeys - remove gaps that
+     * overlap with any of this set of keys
+     * @return {number} - how many gaps were removed from the exposed
+     * gaps only (overlapping gaps not yet exposed are also invalidated
+     * but are not accounted for in the returned value)
+     */
+    removeOverlappingGaps(overlappingKeys: OrderedSet<string> | string[]): number {
+        let overlappingKeysSet;
+        if (Array.isArray(overlappingKeys)) {
+            overlappingKeysSet = new OrderedSet(overlappingKeys);
+        } else {
+            overlappingKeysSet = overlappingKeys;
+        }
+        this._stagingUpdates.addUpdateBatch(overlappingKeysSet);
+        return this._exposedGaps.removeOverlappingGaps(overlappingKeysSet);
+    }
+
+    /**
+     * Lookup the next exposed gap that overlaps with [minKey, maxKey]. Internally
+     * chained gaps are coalesced in the response into a single contiguous large gap.
+     *
+     * @param {string} minKey - minimum key overlapping with the returned gap
+     * @param {string} [maxKey] - maximum key overlapping with the returned gap
+     * @return {Promise<GapSetEntry | null>} - result of the lookup if a gap
+     *   was found, null otherwise, as a Promise
+     */
+    lookupGap(minKey: string, maxKey?: string): Promise<GapSetEntry | null> {
+        return this._exposedGaps.lookupGap(minKey, maxKey);
+    }
+
+    /**
+     * Get the maximum weight setting for individual gaps.
+     *
+     * @return {number} - maximum weight of individual gaps
+     */
+    get maxGapWeight(): number {
+        return this._exposedGaps.maxWeight;
+    }
+
+    /**
+     * Set the maximum weight setting for individual gaps.
+     *
+     * @param {number} gapWeight - maximum weight of individual gaps
+     */
+    set maxGapWeight(gapWeight: number) {
+        this._exposedGaps.maxWeight = gapWeight;
+        // also update transient gap sets
+        this._stagingUpdates.newGaps.maxWeight = gapWeight;
+        this._frozenUpdates.newGaps.maxWeight = gapWeight;
+    }
+
+    /**
+     * Get the exposure delay in milliseconds, which is the minimum
+     * time after which newly cached gaps will be exposed by
+     * lookupGap().
+     *
+     * @return {number} - exposure delay in milliseconds
+     */
+    get exposureDelayMs(): number {
+        return this._exposureDelayMs;
+    }
+
+    /**
+     * Set the exposure delay in milliseconds, which is the minimum
+     * time after which newly cached gaps will be exposed by
+     * lookupGap(). Setting this attribute automatically updates the
+     * internal state to honor the new value.
+     *
+     * @param {number} - exposure delay in milliseconds
+     */
+    set exposureDelayMs(exposureDelayMs: number) {
+        if (exposureDelayMs !== this._exposureDelayMs) {
+            this._exposureDelayMs = exposureDelayMs;
+            if (this._exposeFrozenInterval) {
+                // invalidate all pending gap updates, as the new interval may not be
+                // safe for them
+                this._stagingUpdates = new GapCacheUpdateSet(this.maxGapWeight);
+                this._frozenUpdates = new GapCacheUpdateSet(this.maxGapWeight);
+
+                // reinitialize the _exposeFrozenInterval timer with the updated delay
+                this.stop();
+                this.start();
+            }
+        }
+    }
+
+    /**
+     * Get the number of exposed gaps
+     *
+     * @return {number} number of exposed gaps
+     */
+    get size(): number {
+        return this._exposedGaps.size;
+    }
+
+    /**
+     * Iterate over exposed gaps
+     *
+     * @return {Iterator<GapSetEntry>} an iterator over exposed gaps
+     */
+    [Symbol.iterator](): Iterator<GapSetEntry> {
+        return this._exposedGaps[Symbol.iterator]();
+    }
+
+    /**
+     * Get an array of all exposed gaps
+     *
+     * @return {GapSetEntry[]} array of exposed gaps
+     */
+    toArray(): GapSetEntry[] {
+        return this._exposedGaps.toArray();
+    }
+
+    /**
+     * Clear all exposed and staging gaps from the cache.
+     *
+     * Note: retains invalidating updates from removeOverlappingGaps()
+     * for correctness of gaps inserted afterwards.
+     *
+     * @return {undefined}
+     */
+    clear(): void {
+        this._stagingUpdates.newGaps = new GapSet(this.maxGapWeight);
+        this._frozenUpdates.newGaps = new GapSet(this.maxGapWeight);
+        this._exposedGaps = new GapSet(this.maxGapWeight);
+    }
+}

lib/algos/cache/GapSet.ts

@@ -0,0 +1,366 @@
+import assert from 'assert';
+import { OrderedSet } from '@js-sdsl/ordered-set';
+
+import errors from '../../errors';
+
+export type GapSetEntry = {
+    firstKey: string,
+    lastKey: string,
+    weight: number,
+};
+
+export interface GapSetInterface {
+    maxWeight: number;
+    size: number;
+
+    setGap: (firstKey: string, lastKey: string, weight: number) => GapSetEntry;
+    removeOverlappingGaps: (overlappingKeys: string[]) => number;
+    lookupGap: (minKey: string, maxKey?: string) => Promise<GapSetEntry | null>;
+    [Symbol.iterator]: () => Iterator<GapSetEntry>;
+    toArray: () => GapSetEntry[];
+};
+
+/**
+ * Specialized data structure to support caching of listing "gaps",
+ * i.e. ranges of keys that can be skipped over during listing
+ * (because they only contain delete markers as latest versions)
+ */
+export default class GapSet implements GapSetInterface, Iterable<GapSetEntry> {
+    _gaps: OrderedSet<GapSetEntry>;
+    _maxWeight: number;
+
+    /**
+     * @constructor
+
+     * @param {number} maxWeight - weight threshold for each cached
+     * gap (unitless). Triggers splitting gaps when reached
+     */
+    constructor(maxWeight: number) {
+        this._gaps = new OrderedSet(
+            [],
+            (left: GapSetEntry, right: GapSetEntry) => (
+                left.firstKey < right.firstKey ? -1 :
+                left.firstKey > right.firstKey ? 1 : 0
+            )
+        );
+        this._maxWeight = maxWeight;
+    }
+
+    /**
+     * Create a GapSet from an array of gap entries (used in tests)
+     */
+    static createFromArray(gaps: GapSetEntry[], maxWeight: number): GapSet {
+        const gapSet = new GapSet(maxWeight);
+        for (const gap of gaps) {
+            gapSet._gaps.insert(gap);
+        }
+        return gapSet;
+    }
+
+    /**
+     * Record a gap between two keys, associated with a weight to limit
+     * individual gap sizes in the cache.
+     *
+     * The function handles splitting and merging existing gaps to
+     * maintain an optimal weight of cache entries.
+     *
+     * @param {string} firstKey - first key of the gap
+     * @param {string} lastKey - last key of the gap, must be greater
+     * or equal than 'firstKey'
+     * @param {number} weight - total weight between 'firstKey' and 'lastKey'
+     * @return {GapSetEntry} - existing or new gap entry
+     */
+    setGap(firstKey: string, lastKey: string, weight: number): GapSetEntry {
+        assert(lastKey >= firstKey);
+
+        // Step 1/4: Find the closest left-overlapping gap, and either re-use it
+        // or chain it with a new gap depending on the weights if it exists (otherwise
+        // just creates a new gap).
+        const curGapIt = this._gaps.reverseLowerBound(<GapSetEntry>{ firstKey });
+        let curGap;
+        if (curGapIt.isAccessible()) {
+            curGap = curGapIt.pointer;
+            if (curGap.lastKey >= lastKey) {
+                // return fully overlapping gap already cached
+                return curGap;
+            }
+        }
+        let remainingWeight = weight;
+        if (!curGap                         // no previous gap
+            || curGap.lastKey < firstKey    // previous gap not overlapping
+            || (curGap.lastKey === firstKey // previous gap overlapping by one key...
+                && curGap.weight + weight > this._maxWeight) // ...but we can't extend it
+           ) {
+            // create a new gap indexed by 'firstKey'
+            curGap = { firstKey, lastKey: firstKey, weight: 0 };
+            this._gaps.insert(curGap);
+        } else if (curGap.lastKey > firstKey && weight > this._maxWeight) {
+            // previous gap is either fully or partially contained in the new gap
+            // and cannot be extended: substract its weight from the total (heuristic
+            // in case the previous gap doesn't start at 'firstKey', which is the
+            // uncommon case)
+            remainingWeight -= curGap.weight;
+
+            // there may be an existing chained gap starting with the previous gap's
+            // 'lastKey': use it if it exists
+            const chainedGapIt = this._gaps.find(<GapSetEntry>{ firstKey: curGap.lastKey });
+            if (chainedGapIt.isAccessible()) {
+                curGap = chainedGapIt.pointer;
+            } else {
+                // no existing chained gap: chain a new gap to the previous gap
+                curGap = {
+                    firstKey: curGap.lastKey,
+                    lastKey: curGap.lastKey,
+                    weight: 0,
+                };
+                this._gaps.insert(curGap);
+            }
+        }
+        // Step 2/4: Cleanup existing gaps fully included in firstKey -> lastKey, and
+        // aggregate their weights in curGap to define the minimum weight up to the
+        // last merged gap.
+        let nextGap;
+        while (true) {
+            const nextGapIt = this._gaps.upperBound(<GapSetEntry>{ firstKey: curGap.firstKey });
+            nextGap = nextGapIt.isAccessible() && nextGapIt.pointer;
+            // stop the cleanup when no more gap or if the next gap is not fully
+            // included in curGap
+            if (!nextGap || nextGap.lastKey > lastKey) {
+                break;
+            }
+            this._gaps.eraseElementByIterator(nextGapIt);
+            curGap.lastKey = nextGap.lastKey;
+            curGap.weight += nextGap.weight;
+        }
+
+        // Step 3/4: Extend curGap to lastKey, adjusting the weight.
+        // At this point, curGap weight is the minimum weight of the finished gap, save it
+        // for step 4.
+        let minMergedWeight = curGap.weight;
+        if (curGap.lastKey === firstKey && firstKey !== lastKey) {
+            // extend the existing gap by the full amount 'firstKey -> lastKey'
+            curGap.lastKey = lastKey;
+            curGap.weight += remainingWeight;
+        } else if (curGap.lastKey <= lastKey) {
+            curGap.lastKey = lastKey;
+            curGap.weight = remainingWeight;
+        }
+
+        // Step 4/4: Find the closest right-overlapping gap, and if it exists, either merge
+        // it or chain it with curGap depending on the weights.
+        if (nextGap && nextGap.firstKey <= lastKey) {
+            // nextGap overlaps with the new gap: check if we can merge it
+            minMergedWeight += nextGap.weight;
+            let mergedWeight;
+            if (lastKey === nextGap.firstKey) {
+                // nextGap is chained with curGap: add the full weight of nextGap
+                mergedWeight = curGap.weight + nextGap.weight;
+            } else {
+                // strict overlap: don't add nextGap's weight unless
+                // it's larger than the sum of merged ranges (as it is
+                // then included in `minMergedWeight`)
+                mergedWeight = Math.max(curGap.weight, minMergedWeight);
+            }
+            if (mergedWeight <= this._maxWeight) {
+                // merge nextGap into curGap
+                curGap.lastKey = nextGap.lastKey;
+                curGap.weight = mergedWeight;
+                this._gaps.eraseElementByKey(nextGap);
+            } else {
+                // adjust the last key to chain with nextGap and substract the next
+                // gap's weight from curGap (heuristic)
+                curGap.lastKey = nextGap.firstKey;
+                curGap.weight = Math.max(mergedWeight - nextGap.weight, 0);
+                curGap = nextGap;
+            }
+        }
+        // return a copy of curGap
+        return Object.assign({}, curGap);
+    }
+
+    /**
+     * Remove gaps that overlap with one or more keys in a given array or
+     * OrderedSet. Used to invalidate gaps when keys are inserted or deleted.
+     *
+     * @param {OrderedSet<string> | string[]} overlappingKeys - remove gaps that overlap
+     * with any of this set of keys
+     * @return {number} - how many gaps were removed
+     */
+    removeOverlappingGaps(overlappingKeys: OrderedSet<string> | string[]): number {
+        // To optimize processing with a large number of keys and/or gaps, this function:
+        //
+        // 1. converts the overlappingKeys array to a OrderedSet (if not already a OrderedSet)
+        // 2. queries both the gaps set and the overlapping keys set in a loop, which allows:
+        //    - skipping ranges of overlapping keys at once when there is no new overlapping gap
+        //    - skipping ranges of gaps at once when there is no overlapping key
+        //
+        // This way, it is efficient when the number of non-overlapping gaps is large
+        // (which is the most common case in practice).
+
+        let overlappingKeysSet;
+        if (Array.isArray(overlappingKeys)) {
+            overlappingKeysSet = new OrderedSet(overlappingKeys);
+        } else {
+            overlappingKeysSet = overlappingKeys;
+        }
+        const firstKeyIt = overlappingKeysSet.begin();
+        let currentKey = firstKeyIt.isAccessible() && firstKeyIt.pointer;
+        let nRemoved = 0;
+        while (currentKey) {
+            const closestGapIt = this._gaps.reverseUpperBound(<GapSetEntry>{ firstKey: currentKey });
+            if (closestGapIt.isAccessible()) {
+                const closestGap = closestGapIt.pointer;
+                if (currentKey <= closestGap.lastKey) {
+                    // currentKey overlaps closestGap: remove the gap
+                    this._gaps.eraseElementByIterator(closestGapIt);
+                    nRemoved += 1;
+                }
+            }
+            const nextGapIt = this._gaps.lowerBound(<GapSetEntry>{ firstKey: currentKey });
+            if (!nextGapIt.isAccessible()) {
+                // no more gap: we're done
+                return nRemoved;
+            }
+            const nextGap = nextGapIt.pointer;
+            // advance to the last key potentially overlapping with nextGap
+            let currentKeyIt = overlappingKeysSet.reverseLowerBound(nextGap.lastKey);
+            if (currentKeyIt.isAccessible()) {
+                currentKey = currentKeyIt.pointer;
+                if (currentKey >= nextGap.firstKey) {
+                    // currentKey overlaps nextGap: remove the gap
+                    this._gaps.eraseElementByIterator(nextGapIt);
+                    nRemoved += 1;
+                }
+            }
+            // advance to the first key potentially overlapping with another gap
+            currentKeyIt = overlappingKeysSet.lowerBound(nextGap.lastKey);
+            currentKey = currentKeyIt.isAccessible() && currentKeyIt.pointer;
+        }
+        return nRemoved;
+    }
+
+    /**
+     * Internal helper to coalesce multiple chained gaps into a single gap.
+     *
+     * It is only used to construct lookupGap() return values and
+     * doesn't modify the GapSet.
+     *
+     * NOTE: The function may take a noticeable amount of time and CPU
+     * to execute if a large number of chained gaps have to be
+     * coalesced, but it should never take more than a few seconds. In
+     * most cases it should take less than a millisecond. It regularly
+     * yields to the nodejs event loop to avoid blocking it during a
+     * long execution.
+     *
+     * @param {GapSetEntry} firstGap - first gap of the chain to coalesce with
+     * the next ones in the chain
+     * @return {Promise<GapSetEntry>} - a new coalesced entry, as a Promise
+     */
+    _coalesceGapChain(firstGap: GapSetEntry): Promise<GapSetEntry> {
+        return new Promise(resolve => {
+            const coalescedGap: GapSetEntry = Object.assign({}, firstGap);
+            const coalesceGapChainIteration = () => {
+                // efficiency trade-off: 100 iterations of log(N) complexity lookups should
+                // not block the event loop for too long
+                for (let opCounter = 0; opCounter < 100; ++opCounter) {
+                    const chainedGapIt = this._gaps.find(
+                            <GapSetEntry>{ firstKey: coalescedGap.lastKey });
+                    if (!chainedGapIt.isAccessible()) {
+                        // chain is complete
+                        return resolve(coalescedGap);
+                    }
+                    const chainedGap = chainedGapIt.pointer;
+                    if (chainedGap.firstKey === chainedGap.lastKey) {
+                        // found a single-key gap: chain is complete
+                        return resolve(coalescedGap);
+                    }
+                    coalescedGap.lastKey = chainedGap.lastKey;
+                    coalescedGap.weight += chainedGap.weight;
+                }
+                // yield to the event loop before continuing the process
+                // of coalescing the gap chain
+                return process.nextTick(coalesceGapChainIteration);
+            };
+            coalesceGapChainIteration();
+        });
+    }
+
+    /**
+     * Lookup the next gap that overlaps with [minKey, maxKey]. Internally chained
+     * gaps are coalesced in the response into a single contiguous large gap.
+     *
+     * @param {string} minKey - minimum key overlapping with the returned gap
+     * @param {string} [maxKey] - maximum key overlapping with the returned gap
+     * @return {Promise<GapSetEntry | null>} - result of the lookup if a gap
+     *   was found, null otherwise, as a Promise
+     */
+    async lookupGap(minKey: string, maxKey?: string): Promise<GapSetEntry | null> {
+        let firstGap: GapSetEntry | null = null;
+        const minGapIt = this._gaps.reverseLowerBound(<GapSetEntry>{ firstKey: minKey });
+        const minGap = minGapIt.isAccessible() && minGapIt.pointer;
+        if (minGap && minGap.lastKey >= minKey) {
+            firstGap = minGap;
+        } else {
+            const maxGapIt = this._gaps.upperBound(<GapSetEntry>{ firstKey: minKey });
+            const maxGap = maxGapIt.isAccessible() && maxGapIt.pointer;
+            if (maxGap && (maxKey === undefined || maxGap.firstKey <= maxKey)) {
+                firstGap = maxGap;
+            }
+        }
+        if (!firstGap) {
+            return null;
+        }
+        return this._coalesceGapChain(firstGap);
+    }
+
+    /**
+     * Get the maximum weight setting for individual gaps.
+     *
+     * @return {number} - maximum weight of individual gaps
+     */
+    get maxWeight(): number {
+        return this._maxWeight;
+    }
+
+    /**
+     * Set the maximum weight setting for individual gaps.
+     *
+     * @param {number} gapWeight - maximum weight of individual gaps
+     */
+    set maxWeight(gapWeight: number) {
+        this._maxWeight = gapWeight;
+    }
+
+    /**
+     * Get the number of gaps stored in this set.
+     *
+     * @return {number} - number of gaps stored in this set
+     */
+    get size(): number {
+        return this._gaps.size();
+    }
+
+    /**
+     * Iterate over each gap of the set, ordered by first key
+     *
+     * @return {Iterator<GapSetEntry>} - an iterator over all gaps
+     *   Example:
+     *     for (const gap of myGapSet) { ... }
+     */
+    [Symbol.iterator](): Iterator<GapSetEntry> {
+        return this._gaps[Symbol.iterator]();
+    }
+
+    /**
+     * Return an array containing all gaps, ordered by first key
+     *
+     * NOTE: there is a toArray() method in the OrderedSet implementation
+     * but it does not scale well and overflows the stack quickly. This is
+     * why we provide an implementation based on an iterator.
+     *
+     * @return {GapSetEntry[]} - an array containing all gaps
+     */
+    toArray(): GapSetEntry[] {
+        return [...this];
+    }
+}

lib/algos/cache/LRUCache.js

@@ -0,0 +1,167 @@
+const assert = require('assert');
+
+/**
+ * @class
+ * @classdesc Implements a key-value in-memory cache with a capped
+ * number of items and a Least Recently Used (LRU) strategy for
+ * eviction.
+ */
+class LRUCache {
+    /**
+     * @constructor
+     * @param {number} maxEntries - maximum number of entries kept in
+     * the cache
+     */
+    constructor(maxEntries) {
+        assert(maxEntries >= 1);
+        this._maxEntries = maxEntries;
+        this.clear();
+    }
+
+    /**
+     * Add or update the value associated to a key in the cache,
+     * making it the most recently accessed for eviction purpose.
+     *
+     * @param {string} key - key to add
+     * @param {object} value - associated value (can be of any type)
+     * @return {boolean} true if the cache contained an entry with
+     * this key, false if it did not
+     */
+    add(key, value) {
+        let entry = this._entryMap[key];
+        if (entry) {
+            entry.value = value;
+            // make the entry the most recently used by re-pushing it
+            // to the head of the LRU list
+            this._lruRemoveEntry(entry);
+            this._lruPushEntry(entry);
+            return true;
+        }
+        if (this._entryCount === this._maxEntries) {
+            // if the cache is already full, abide by the LRU strategy
+            // and remove the least recently used entry from the cache
+            // before pushing the new entry
+            this._removeEntry(this._lruTail);
+        }
+        entry = { key, value };
+        this._entryMap[key] = entry;
+        this._entryCount += 1;
+        this._lruPushEntry(entry);
+        return false;
+    }
+
+    /**
+     * Get the value associated to a key in the cache, making it the
+     * most recently accessed for eviction purpose.
+     *
+     * @param {string} key - key of which to fetch the associated value
+     * @return {object|undefined} - returns the associated value if
+     * exists in the cache, or undefined if not found - either if the
+     * key was never added or if it has been evicted from the cache.
+     */
+    get(key) {
+        const entry = this._entryMap[key];
+        if (entry) {
+            // make the entry the most recently used by re-pushing it
+            // to the head of the LRU list
+            this._lruRemoveEntry(entry);
+            this._lruPushEntry(entry);
+            return entry.value;
+        }
+        return undefined;
+    }
+
+    /**
+     * Remove an entry from the cache if exists
+     *
+     * @param {string} key - key to remove
+     * @return {boolean} true if an entry has been removed, false if
+     * there was no entry with this key in the cache - either if the
+     * key was never added or if it has been evicted from the cache.
+     */
+    remove(key) {
+        const entry = this._entryMap[key];
+        if (entry) {
+            this._removeEntry(entry);
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Get the current number of cached entries
+     *
+     * @return {number} current number of cached entries
+     */
+    count() {
+        return this._entryCount;
+    }
+
+    /**
+     * Remove all entries from the cache
+     *
+     * @return {undefined}
+     */
+    clear() {
+        this._entryMap = {};
+        this._entryCount = 0;
+        this._lruHead = null;
+        this._lruTail = null;
+    }
+
+    /**
+     * Push an entry to the front of the LRU list, making it the most
+     * recently accessed
+     *
+     * @param {object} entry - entry to push
+     * @return {undefined}
+     */
+    _lruPushEntry(entry) {
+        /* eslint-disable no-param-reassign */
+        entry._lruNext = this._lruHead;
+        entry._lruPrev = null;
+        if (this._lruHead) {
+            this._lruHead._lruPrev = entry;
+        }
+        this._lruHead = entry;
+        if (!this._lruTail) {
+            this._lruTail = entry;
+        }
+        /* eslint-enable no-param-reassign */
+    }
+
+    /**
+     * Remove an entry from the LRU list
+     *
+     * @param {object} entry - entry to remove
+     * @return {undefined}
+     */
+    _lruRemoveEntry(entry) {
+        /* eslint-disable no-param-reassign */
+        if (entry._lruPrev) {
+            entry._lruPrev._lruNext = entry._lruNext;
+        } else {
+            this._lruHead = entry._lruNext;
+        }
+        if (entry._lruNext) {
+            entry._lruNext._lruPrev = entry._lruPrev;
+        } else {
+            this._lruTail = entry._lruPrev;
+        }
+        /* eslint-enable no-param-reassign */
+    }
+
+    /**
+     * Helper function to remove an existing entry from the cache
+     *
+     * @param {object} entry - cache entry to remove
+     * @return {undefined}
+     */
+    _removeEntry(entry) {
+        this._lruRemoveEntry(entry);
+        delete this._entryMap[entry.key];
+        this._entryCount -= 1;
+    }
+}
+
+module.exports = LRUCache;

lib/algos/heap/Heap.ts

@@ -0,0 +1,124 @@
+export enum HeapOrder {
+    Min = -1,
+    Max = 1,
+}
+
+export enum CompareResult {
+    LT = -1,
+    EQ = 0,
+    GT = 1,
+}
+
+export type CompareFunction = (x: any, y: any) => CompareResult;
+
+export class Heap {
+    size: number;
+    _maxSize: number;
+    _order: HeapOrder;
+    _heap: any[];
+    _cmpFn: CompareFunction;
+    
+    constructor(size: number, order: HeapOrder, cmpFn: CompareFunction) {
+        this.size = 0;
+        this._maxSize = size;
+        this._order = order;
+        this._cmpFn = cmpFn;
+        this._heap = new Array<any>(this._maxSize);
+    }
+
+    _parent(i: number): number {
+        return Math.floor((i - 1) / 2);
+    }
+
+    _left(i: number): number {
+        return Math.floor((2 * i) + 1);
+    }
+
+    _right(i: number): number {
+        return Math.floor((2 * i) + 2);
+    }
+
+    _shouldSwap(childIdx: number, parentIdx: number): boolean {
+        return this._cmpFn(this._heap[childIdx], this._heap[parentIdx]) as number === this._order as number;
+    }
+
+    _swap(i: number, j: number) {
+        const tmp = this._heap[i];
+        this._heap[i] = this._heap[j];
+        this._heap[j] = tmp;
+    }
+
+    _heapify(i: number) {
+        const l = this._left(i);
+        const r = this._right(i);
+        let c = i;
+
+        if (l < this.size && this._shouldSwap(l, c)) {
+            c = l;
+        }
+
+        if (r < this.size && this._shouldSwap(r, c)) {
+            c = r;
+        }
+
+        if (c != i) {
+            this._swap(c, i);
+            this._heapify(c);
+        }
+    }
+
+    add(item: any): any {
+        if (this.size >= this._maxSize) {
+            return new Error('Max heap size reached');
+        }
+
+        ++this.size;
+        let c = this.size - 1;
+        this._heap[c] = item;
+
+        while (c > 0) {
+            if (!this._shouldSwap(c, this._parent(c))) {
+                return null;
+            }
+
+            this._swap(c, this._parent(c));
+            c = this._parent(c);
+        }
+
+        return null;
+    };
+
+    remove(): any {
+        if (this.size <= 0) {
+            return null;
+        }
+
+        const ret = this._heap[0];
+        this._heap[0] = this._heap[this.size - 1];
+        this._heapify(0);
+        --this.size;
+
+        return ret;
+    };
+
+    peek(): any {
+        if (this.size <= 0) {
+            return null;
+        }
+
+        return this._heap[0];
+    };
+}
+
+export class MinHeap extends Heap {
+    constructor(size: number, cmpFn: CompareFunction) {
+        super(size, HeapOrder.Min, cmpFn);
+    }
+}
+
+export class MaxHeap extends Heap {
+    constructor(size: number, cmpFn: CompareFunction) {
+        super(size, HeapOrder.Max, cmpFn);
+    }
+} 
+

lib/algos/list/Extension.js

@@ -0,0 +1,129 @@
+'use strict'; // eslint-disable-line strict
+
+const { FILTER_ACCEPT, SKIP_NONE } = require('./tools');
+
+// Use a heuristic to amortize the cost of JSON
+// serialization/deserialization only on largest metadata where the
+// potential for size reduction is high, considering the bulk of the
+// blob size is due to the "location" field containing a large number
+// of MPU parts.
+//
+// Measured on some standard metadata:
+// - 100 parts -> 9K blob
+// - 2000 parts -> 170K blob
+//
+// Using a 10K threshold should lead to a worst case of about 10M to
+// store a raw listing of 1000 entries, even with some growth
+// multiplication factor due to some internal memory duplication, it
+// should stay within reasonable memory limits.
+
+const TRIM_METADATA_MIN_BLOB_SIZE = 10000;
+
+/**
+ *  Base class of listing extensions.
+ */
+class Extension {
+    /**
+     * This takes a list of parameters and a logger as the inputs.
+     * Derivatives should have their own format regarding parameters.
+     *
+     * @param {Object} parameters - listing parameter from applications
+     * @param {RequestLogger} logger - the logger
+     * @constructor
+     */
+    constructor(parameters, logger) {
+        // inputs
+        this.parameters = parameters;
+        this.logger = logger;
+        // listing results
+        this.res = undefined;
+        this.keys = 0;
+    }
+
+    /**
+     * Filters-out non-requested optional fields from the value. This function
+     * shall be applied on any value that is to be returned as part of the
+     * result of a listing extension.
+     *
+     * @param {String} value - The JSON value of a listing item
+     *
+     * @return {String} The value that may have been trimmed of some
+     * heavy unused fields, or left untouched (depending on size
+     * heuristics)
+     */
+    trimMetadata(value) {
+        let ret = undefined;
+        if (value.length >= TRIM_METADATA_MIN_BLOB_SIZE) {
+            try {
+                ret = JSON.parse(value);
+                delete ret.location;
+                ret = JSON.stringify(ret);
+            } catch (e) {
+                // Prefer returning an unfiltered data rather than
+                // stopping the service in case of parsing failure.
+                // The risk of this approach is a potential
+                // reproduction of MD-692, where too much memory is
+                // used by repd.
+                this.logger.warn(
+                    'Could not parse Object Metadata while listing',
+                    { err: e.toString() });
+            }
+        }
+        return ret || value;
+    }
+
+    /**
+     * Generates listing parameters that metadata can understand from the input
+     * parameters. What metadata can understand: gt, gte, lt, lte, limit, keys,
+     * values, reverse; we use the same set of parameters as levelup's.
+     * Derivatives should have their own conversion of their original listing
+     * parameters into metadata listing parameters.
+     *
+     * @return {object} - listing parameters for metadata
+     */
+    genMDParams() {
+        return {};
+    }
+
+    /**
+     * This function receives a data entry from metadata and decides if it will
+     * include the entry in the listing result or not.
+     *
+     * @param {object} entry - a listing entry from metadata
+     *                         expected format: { key, value }
+     * @return {number} - result of filtering the entry:
+     *                    FILTER_ACCEPT: entry is accepted and may or not be included
+     *                                   in the result
+     *                    FILTER_SKIP: listing may skip directly (with "gte" param) to
+     *                                 the key returned by the skipping() method
+     *                    FILTER_END: the results are complete, listing can be stopped
+     */
+    filter(/* entry: { key, value } */) {
+        return FILTER_ACCEPT;
+    }
+
+    /**
+     * Provides the next key at which the listing task is allowed to skip to.
+     * This could allow to skip over:
+     * - a key prefix ending with the delimiter
+     * - all remaining versions of an object when doing a current
+     *   versions listing in v0 format
+     * - a cached "gap" of deleted objects when doing a current
+     *   versions listing in v0 format
+     *
+     * @return {string} - the next key at which the listing task is allowed to skip to
+     */
+    skipping() {
+        return SKIP_NONE;
+    }
+
+    /**
+     * Get the listing resutls. Format depends on derivatives' specific logic.
+     * @return {Array} - The listed elements
+     */
+    result() {
+        return this.res;
+    }
+}
+
+module.exports.default = Extension;

lib/algos/list/MPU.js

@@ -0,0 +1,188 @@
+'use strict'; // eslint-disable-line strict
+
+const { inc, checkLimit, listingParamsMasterKeysV0ToV1,
+    FILTER_END, FILTER_ACCEPT, SKIP_NONE } = require('./tools');
+const DEFAULT_MAX_KEYS = 1000;
+const VSConst = require('../../versioning/constants').VersioningConstants;
+const { DbPrefixes, BucketVersioningKeyFormat } = VSConst;
+
+function numberDefault(num, defaultNum) {
+    const parsedNum = Number.parseInt(num, 10);
+    return Number.isNaN(parsedNum) ? defaultNum : parsedNum;
+}
+
+/**
+ *  Class for the MultipartUploads extension
+ */
+class MultipartUploads {
+    /**
+     *  Constructor of the extension
+     *  Init and check parameters
+     *  @param {Object} params - The parameters you sent to DBD
+     *  @param {RequestLogger} logger - The logger of the request
+     *  @param {String} [vFormat] - versioning key format
+     *  @return {undefined}
+     */
+    constructor(params, logger, vFormat) {
+        this.params = params;
+        this.vFormat = vFormat || BucketVersioningKeyFormat.v0;
+        this.CommonPrefixes = [];
+        this.Uploads = [];
+        this.IsTruncated = false;
+        this.NextKeyMarker = '';
+        this.NextUploadIdMarker = '';
+        this.prefixLength = 0;
+        this.queryPrefixLength = numberDefault(params.queryPrefixLength, 0);
+        this.keys = 0;
+        this.maxKeys = checkLimit(params.maxKeys, DEFAULT_MAX_KEYS);
+        this.delimiter = params.delimiter;
+        this.splitter = params.splitter;
+        this.logger = logger;
+
+        Object.assign(this, {
+            [BucketVersioningKeyFormat.v0]: {
+                genMDParams: this.genMDParamsV0,
+                getObjectKey: this.getObjectKeyV0,
+            },
+            [BucketVersioningKeyFormat.v1]: {
+                genMDParams: this.genMDParamsV1,
+                getObjectKey: this.getObjectKeyV1,
+            },
+        }[this.vFormat]);
+    }
+
+    genMDParamsV0() {
+        const params = {};
+        if (this.params.keyMarker) {
+            params.gt = `overview${this.params.splitter}` +
+                `${this.params.keyMarker}${this.params.splitter}`;
+            if (this.params.uploadIdMarker) {
+                params.gt += `${this.params.uploadIdMarker}`;
+            }
+            // advance so that lower bound does not include the supplied
+            // markers
+            params.gt = inc(params.gt);
+        }
+        if (this.params.prefix) {
+            if (params.gt === undefined || this.params.prefix > params.gt) {
+                delete params.gt;
+                params.gte = this.params.prefix;
+            }
+            params.lt = inc(this.params.prefix);
+        }
+        return params;
+    }
+
+    genMDParamsV1() {
+        const v0params = this.genMDParamsV0();
+        return listingParamsMasterKeysV0ToV1(v0params);
+    }
+
+    /**
+     *  This function adds the elements to the Uploads
+     *  Set the NextKeyMarker to the current key
+     *  Increment the keys counter
+     *  @param {String} value - The value of the key
+     *  @return {undefined}
+     */
+    addUpload(value) {
+        const tmp = JSON.parse(value);
+        this.Uploads.push({
+            key: tmp.key,
+            value: {
+                UploadId: tmp.uploadId,
+                Initiator: {
+                    ID: tmp.initiator.ID,
+                    DisplayName: tmp.initiator.DisplayName,
+                },
+                Owner: {
+                    ID: tmp['owner-id'],
+                    DisplayName: tmp['owner-display-name'],
+                },
+                StorageClass: tmp['x-amz-storage-class'],
+                Initiated: tmp.initiated,
+            },
+        });
+        this.NextKeyMarker = tmp.key;
+        this.NextUploadIdMarker = tmp.uploadId;
+        ++this.keys;
+    }
+    /**
+     *  This function adds a common prefix to the CommonPrefixes array
+     *  Set the NextKeyMarker to the current commonPrefix
+     *  Increment the keys counter
+     *  @param {String} commonPrefix - The commonPrefix to add
+     *  @return {undefined}
+     */
+    addCommonPrefix(commonPrefix) {
+        if (this.CommonPrefixes.indexOf(commonPrefix) === -1) {
+            this.CommonPrefixes.push(commonPrefix);
+            this.NextKeyMarker = commonPrefix;
+            ++this.keys;
+        }
+    }
+
+    getObjectKeyV0(obj) {
+        return obj.key;
+    }
+
+    getObjectKeyV1(obj) {
+        return obj.key.slice(DbPrefixes.Master.length);
+    }
+
+    /**
+     *  This function applies filter on each element
+     *  @param {String} obj - The key and value of the element
+     *  @return {number} - > 0: Continue, < 0: Stop
+     */
+    filter(obj) {
+        // Check first in case of maxkeys = 0
+        if (this.keys >= this.maxKeys) {
+            // In cases of maxKeys <= 0 => IsTruncated = false
+            this.IsTruncated = this.maxKeys > 0;
+            return FILTER_END;
+        }
+        const key = this.getObjectKey(obj);
+        const value = obj.value;
+        if (this.delimiter) {
+            const mpuPrefixSlice = `overview${this.splitter}`.length;
+            const mpuKey = key.slice(mpuPrefixSlice);
+            const commonPrefixIndex = mpuKey.indexOf(this.delimiter,
+                this.queryPrefixLength);
+
+            if (commonPrefixIndex === -1) {
+                this.addUpload(value);
+            } else {
+                this.addCommonPrefix(mpuKey.substring(0,
+                    commonPrefixIndex + this.delimiter.length));
+            }
+        } else {
+            this.addUpload(value);
+        }
+        return FILTER_ACCEPT;
+    }
+
+    skipping() {
+        return SKIP_NONE;
+    }
+
+    /**
+     *  Returns the formatted result
+     *  @return {Object} - The result.
+     */
+    result() {
+        return {
+            CommonPrefixes: this.CommonPrefixes,
+            Uploads: this.Uploads,
+            IsTruncated: this.IsTruncated,
+            NextKeyMarker: this.NextKeyMarker,
+            MaxKeys: this.maxKeys,
+            NextUploadIdMarker: this.NextUploadIdMarker,
+            Delimiter: this.delimiter,
+        };
+    }
+}
+
+module.exports = {
+    MultipartUploads,
+};

lib/algos/list/basic.js

@@ -0,0 +1,127 @@
+'use strict'; // eslint-disable-line strict
+
+const Extension = require('./Extension').default;
+
+const { checkLimit, FILTER_END, FILTER_ACCEPT } = require('./tools');
+const DEFAULT_MAX_KEYS = 10000;
+
+/**
+ *  Class of an extension doing the simple listing
+ */
+class List extends Extension {
+    /**
+     *  Constructor
+     *  Set the logger and the res
+     *  @param {Object} parameters - The parameters you sent to DBD
+     *  @param {RequestLogger} logger - The logger of the request
+     *  @return {undefined}
+     */
+    constructor(parameters, logger) {
+        super(parameters, logger);
+        this.res = [];
+        if (parameters) {
+            this.maxKeys = checkLimit(parameters.maxKeys, DEFAULT_MAX_KEYS);
+            this.filterKey = parameters.filterKey;
+            this.filterKeyStartsWith = parameters.filterKeyStartsWith;
+        } else {
+            this.maxKeys = DEFAULT_MAX_KEYS;
+        }
+        this.keys = 0;
+    }
+
+    genMDParams() {
+        const params = this.parameters ? {
+            gt: this.parameters.gt,
+            gte: this.parameters.gte || this.parameters.start,
+            lt: this.parameters.lt,
+            lte: this.parameters.lte || this.parameters.end,
+            keys: this.parameters.keys,
+            values: this.parameters.values,
+        } : {};
+        Object.keys(params).forEach(key => {
+            if (params[key] === null || params[key] === undefined) {
+                delete params[key];
+            }
+        });
+        return params;
+    }
+
+    /**
+     * Filters customAttributes sub-object if present
+     *
+     * @param {String} value - The JSON value of a listing item
+     *
+     * @return {Boolean} Returns true if matches, else false.
+     */
+    customFilter(value) {
+        let _value;
+        try {
+            _value = JSON.parse(value);
+        } catch (e) {
+            // Prefer returning an unfiltered data rather than
+            // stopping the service in case of parsing failure.
+            // The risk of this approach is a potential
+            // reproduction of MD-692, where too much memory is
+            // used by repd.
+            this.logger.warn(
+                'Could not parse Object Metadata while listing',
+                { err: e.toString() });
+            return false;
+        }
+        if (_value.customAttributes !== undefined) {
+            for (const key of Object.keys(_value.customAttributes)) {
+                if (this.filterKey !== undefined &&
+                    key === this.filterKey) {
+                    return true;
+                }
+                if (this.filterKeyStartsWith !== undefined &&
+                    key.startsWith(this.filterKeyStartsWith)) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    /**
+     *  Function apply on each element
+     *  Just add it to the array
+     *  @param {Object} elem - The data from the database
+     *  @return {number} - > 0 : continue listing
+     *                     < 0 : listing done
+     */
+    filter(elem) {
+        // Check if the result array is full
+        if (this.keys >= this.maxKeys) {
+            return FILTER_END;
+        }
+        if ((this.filterKey !== undefined ||
+             this.filterKeyStartsWith !== undefined) &&
+            typeof elem === 'object' &&
+            !this.customFilter(elem.value)) {
+            return FILTER_ACCEPT;
+        }
+        if (typeof elem === 'object') {
+            this.res.push({
+                key: elem.key,
+                value: this.trimMetadata(elem.value),
+            });
+        } else {
+            this.res.push(elem);
+        }
+        this.keys++;
+        return FILTER_ACCEPT;
+    }
+
+    /**
+     *  Function returning the result
+     *  @return {Array} - The listed elements
+     */
+    result() {
+        return this.res;
+    }
+}
+
+module.exports = {
+    List,
+};

lib/algos/list/delimiter.ts

@@ -0,0 +1,356 @@
+'use strict'; // eslint-disable-line strict
+
+const Extension = require('./Extension').default;
+const { inc, listingParamsMasterKeysV0ToV1,
+    FILTER_END, FILTER_ACCEPT, FILTER_SKIP, SKIP_NONE } = require('./tools');
+const VSConst = require('../../versioning/constants').VersioningConstants;
+const { DbPrefixes, BucketVersioningKeyFormat } = VSConst;
+
+export interface FilterState {
+    id: number,
+};
+
+export interface FilterReturnValue {
+    FILTER_ACCEPT,
+    FILTER_SKIP,
+    FILTER_END,
+};
+
+export const enum DelimiterFilterStateId {
+    NotSkipping = 1,
+    SkippingPrefix = 2,
+};
+
+export interface DelimiterFilterState_NotSkipping extends FilterState {
+    id: DelimiterFilterStateId.NotSkipping,
+};
+
+export interface DelimiterFilterState_SkippingPrefix extends FilterState {
+    id: DelimiterFilterStateId.SkippingPrefix,
+    prefix: string;
+};
+
+type KeyHandler = (key: string, value: string) => FilterReturnValue;
+
+export type ResultObject = {
+    CommonPrefixes: string[];
+    Contents: {
+        key: string;
+        value: string;
+    }[];
+    IsTruncated: boolean;
+    Delimiter ?: string;
+    NextMarker ?: string;
+    NextContinuationToken ?: string;
+};
+
+/**
+ * Handle object listing with parameters
+ *
+ * @prop {String[]} CommonPrefixes     - 'folders' defined by the delimiter
+ * @prop {String[]} Contents           - 'files' to list
+ * @prop {Boolean} IsTruncated         - truncated listing flag
+ * @prop {String|undefined} NextMarker - marker per amazon format
+ * @prop {Number} keys                 - count of listed keys
+ * @prop {String|undefined} delimiter  - separator per amazon format
+ * @prop {String|undefined} prefix     - prefix per amazon format
+ * @prop {Number} maxKeys              - number of keys to list
+ */
+export class Delimiter extends Extension {
+
+    state: FilterState;
+    keyHandlers: { [id: number]: KeyHandler };
+
+    /**
+     * Create a new Delimiter instance
+     * @constructor
+     * @param {Object}  parameters                     - listing parameters
+     * @param {String}  [parameters.delimiter]         - delimiter per amazon
+     *                                                   format
+     * @param {String}  [parameters.prefix]            - prefix per amazon
+     *                                                   format
+     * @param {String}  [parameters.marker]            - marker per amazon
+     *                                                   format
+     * @param {Number}  [parameters.maxKeys]           - number of keys to list
+     * @param {Boolean} [parameters.v2]                - indicates whether v2
+     *                                                   format
+     * @param {String}  [parameters.startAfter]        - marker per amazon
+     *                                                   format
+     * @param {String}  [parameters.continuationToken] - obfuscated amazon
+     *                                                   token
+     * @param {RequestLogger} logger                   - The logger of the
+     *                                                   request
+     * @param {String} [vFormat]                       - versioning key format
+     */
+    constructor(parameters, logger, vFormat) {
+        super(parameters, logger);
+        // original listing parameters
+        this.delimiter = parameters.delimiter;
+        this.prefix = parameters.prefix;
+        this.maxKeys = parameters.maxKeys || 1000;
+
+        if (parameters.v2) {
+            this.marker = parameters.continuationToken || parameters.startAfter;
+        } else {
+            this.marker = parameters.marker;
+        }
+        this.nextMarker = this.marker;
+
+        this.vFormat = vFormat || BucketVersioningKeyFormat.v0;
+        // results
+        this.CommonPrefixes = [];
+        this.Contents = [];
+        this.IsTruncated = false;
+        this.keyHandlers = {};
+
+        Object.assign(this, {
+            [BucketVersioningKeyFormat.v0]: {
+                genMDParams: this.genMDParamsV0,
+                getObjectKey: this.getObjectKeyV0,
+                skipping: this.skippingV0,
+            },
+            [BucketVersioningKeyFormat.v1]: {
+                genMDParams: this.genMDParamsV1,
+                getObjectKey: this.getObjectKeyV1,
+                skipping: this.skippingV1,
+            },
+        }[this.vFormat]);
+
+        // if there is a delimiter, we may skip ranges by prefix,
+        // hence using the NotSkippingPrefix flavor that checks the
+        // subprefix up to the delimiter for the NotSkipping state
+        if (this.delimiter) {
+            this.setKeyHandler(
+                DelimiterFilterStateId.NotSkipping,
+                this.keyHandler_NotSkippingPrefix.bind(this));
+        } else {
+            // listing without a delimiter never has to skip over any
+            // prefix -> use NeverSkipping flavor for the NotSkipping
+            // state
+            this.setKeyHandler(
+                DelimiterFilterStateId.NotSkipping,
+                this.keyHandler_NeverSkipping.bind(this));
+        }
+        this.setKeyHandler(
+            DelimiterFilterStateId.SkippingPrefix,
+            this.keyHandler_SkippingPrefix.bind(this));
+
+        this.state = <DelimiterFilterState_NotSkipping> {
+            id: DelimiterFilterStateId.NotSkipping,
+        };
+    }
+
+    genMDParamsV0() {
+        const params: { gt ?: string, gte ?: string, lt ?: string } = {};
+        if (this.prefix) {
+            params.gte = this.prefix;
+            params.lt = inc(this.prefix);
+        }
+        if (this.marker && this.delimiter) {
+            const commonPrefix = this.getCommonPrefix(this.marker);
+            if (commonPrefix) {
+                const afterPrefix = inc(commonPrefix);
+                if (!params.gte || afterPrefix > params.gte) {
+                    params.gte = afterPrefix;
+                }
+            }
+        }
+        if (this.marker && (!params.gte || this.marker >= params.gte)) {
+            delete params.gte;
+            params.gt = this.marker;
+        }
+        return params;
+    }
+
+    genMDParamsV1() {
+        const params = this.genMDParamsV0();
+        return listingParamsMasterKeysV0ToV1(params);
+    }
+
+    /**
+     * check if the max keys count has been reached and set the
+     * final state of the result if it is the case
+     * @return {Boolean} - indicates if the iteration has to stop
+     */
+    _reachedMaxKeys(): boolean {
+        if (this.keys >= this.maxKeys) {
+            // In cases of maxKeys <= 0 -> IsTruncated = false
+            this.IsTruncated = this.maxKeys > 0;
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     *  Add a (key, value) tuple to the listing
+     *  Set the NextMarker to the current key
+     *  Increment the keys counter
+     *  @param {String} key   - The key to add
+     *  @param {String} value - The value of the key
+     *  @return {number}      - indicates if iteration should continue
+     */
+    addContents(key: string, value: string): void {
+        this.Contents.push({ key, value: this.trimMetadata(value) });
+        ++this.keys;
+        this.nextMarker = key;
+    }
+
+    getCommonPrefix(key: string): string | undefined {
+        if (!this.delimiter) {
+            return undefined;
+        }
+        const baseIndex = this.prefix ? this.prefix.length : 0;
+        const delimiterIndex = key.indexOf(this.delimiter, baseIndex);
+        if (delimiterIndex === -1) {
+            return undefined;
+        }
+        return key.substring(0, delimiterIndex + this.delimiter.length);
+    }
+
+    /**
+     * Add a Common Prefix in the list
+     * @param {String} commonPrefix   - common prefix to add
+     * @param {String} key            - full key starting with commonPrefix
+     * @return {Boolean}     - indicates if iteration should continue
+     */
+    addCommonPrefix(commonPrefix: string, key: string): void {
+        // add the new prefix to the list
+        this.CommonPrefixes.push(commonPrefix);
+        ++this.keys;
+        this.nextMarker = commonPrefix;
+    }
+
+    addCommonPrefixOrContents(key: string, value: string): string | undefined {
+        // add the subprefix to the common prefixes if the key has the delimiter
+        const commonPrefix = this.getCommonPrefix(key);
+        if (commonPrefix) {
+            this.addCommonPrefix(commonPrefix, key);
+            return commonPrefix;
+        }
+        this.addContents(key, value);
+        return undefined;
+    }
+
+    getObjectKeyV0(obj: { key: string }): string {
+        return obj.key;
+    }
+
+    getObjectKeyV1(obj: { key: string }): string {
+        return obj.key.slice(DbPrefixes.Master.length);
+    }
+
+    /**
+     *  Filter to apply on each iteration, based on:
+     *  - prefix
+     *  - delimiter
+     *  - maxKeys
+     *  The marker is being handled directly by levelDB
+     *  @param {Object} obj       - The key and value of the element
+     *  @param {String} obj.key   - The key of the element
+     *  @param {String} obj.value - The value of the element
+     *  @return {number}          - indicates if iteration should continue
+     */
+    filter(obj: { key: string, value: string }): FilterReturnValue {
+        const key = this.getObjectKey(obj);
+        const value = obj.value;
+
+        return this.handleKey(key, value);
+    }
+
+    setState(state: FilterState): void {
+        this.state = state;
+    }
+
+    setKeyHandler(stateId: number, keyHandler: KeyHandler): void {
+        this.keyHandlers[stateId] = keyHandler;
+    }
+
+    handleKey(key: string, value: string): FilterReturnValue {
+        return this.keyHandlers[this.state.id](key, value);
+    }
+
+    keyHandler_NeverSkipping(key: string, value: string): FilterReturnValue {
+        if (this._reachedMaxKeys()) {
+            return FILTER_END;
+        }
+        this.addContents(key, value);
+        return FILTER_ACCEPT;
+    }
+
+    keyHandler_NotSkippingPrefix(key: string, value: string): FilterReturnValue {
+        if (this._reachedMaxKeys()) {
+            return FILTER_END;
+        }
+        const commonPrefix = this.addCommonPrefixOrContents(key, value);
+        if (commonPrefix) {
+            // transition into SkippingPrefix state to skip all following keys
+            // while they start with the same prefix
+            this.setState(<DelimiterFilterState_SkippingPrefix> {
+                id: DelimiterFilterStateId.SkippingPrefix,
+                prefix: commonPrefix,
+            });
+        }
+        return FILTER_ACCEPT;
+    }
+
+    keyHandler_SkippingPrefix(key: string, value: string): FilterReturnValue {
+        const { prefix } = <DelimiterFilterState_SkippingPrefix> this.state;
+        if (key.startsWith(prefix)) {
+            return FILTER_SKIP;
+        }
+        this.setState(<DelimiterFilterState_NotSkipping> {
+            id: DelimiterFilterStateId.NotSkipping,
+        });
+        return this.handleKey(key, value);
+    }
+
+    skippingBase(): string | undefined {
+        switch (this.state.id) {
+        case DelimiterFilterStateId.SkippingPrefix:
+            const { prefix } = <DelimiterFilterState_SkippingPrefix> this.state;
+            return inc(prefix);
+
+        default:
+            return SKIP_NONE;
+        }
+    }
+
+    skippingV0() {
+        return this.skippingBase();
+    }
+
+    skippingV1() {
+        const skipTo = this.skippingBase();
+        if (skipTo === SKIP_NONE) {
+            return SKIP_NONE;
+        }
+        return DbPrefixes.Master + skipTo;
+    }
+
+    /**
+     *  Return an object containing all mandatory fields to use once the
+     *  iteration is done, doesn't show a NextMarker field if the output
+     *  isn't truncated
+     *  @return {Object} - following amazon format
+     */
+    result(): ResultObject {
+        /* NextMarker is only provided when delimiter is used.
+         * specified in v1 listing documentation
+         * http://docs.aws.amazon.com/AmazonS3/latest/API/RESTBucketGET.html
+         */
+        const result: ResultObject = {
+            CommonPrefixes: this.CommonPrefixes,
+            Contents: this.Contents,
+            IsTruncated: this.IsTruncated,
+            Delimiter: this.delimiter,
+        };
+        if (this.parameters.v2) {
+            result.NextContinuationToken = this.IsTruncated
+                ? this.nextMarker : undefined;
+        } else {
+            result.NextMarker = (this.IsTruncated && this.delimiter)
+                ? this.nextMarker : undefined;
+        }
+        return result;
+    }
+}

lib/algos/list/delimiterCurrent.ts

@@ -0,0 +1,127 @@
+const { DelimiterMaster } = require('./delimiterMaster');
+const { FILTER_ACCEPT, FILTER_END } = require('./tools');
+
+type ResultObject = {
+    Contents: {
+        key: string;
+        value: string;
+    }[];
+    IsTruncated: boolean;
+    NextMarker ?: string;
+};
+
+/**
+ * Handle object listing with parameters. This extends the base class DelimiterMaster
+ * to return the master/current versions.
+ */
+class DelimiterCurrent extends DelimiterMaster {
+    /**
+     * Delimiter listing of current versions.
+     * @param {Object}  parameters            - listing parameters
+     * @param {String}  parameters.beforeDate - limit the response to keys older than beforeDate
+     * @param {String}  parameters.excludedDataStoreName - excluded datatore name
+     * @param {Number} parameters.maxScannedLifecycleListingEntries - max number of entries to be scanned
+     * @param {RequestLogger} logger          - The logger of the request
+     * @param {String} [vFormat]              - versioning key format
+     */
+    constructor(parameters, logger, vFormat) {
+        super(parameters, logger, vFormat);
+
+        this.beforeDate = parameters.beforeDate;
+        this.excludedDataStoreName = parameters.excludedDataStoreName;
+        this.maxScannedLifecycleListingEntries = parameters.maxScannedLifecycleListingEntries;
+        this.scannedKeys = 0;
+    }
+
+    genMDParamsV0() {
+        const params = super.genMDParamsV0();
+        // lastModified and dataStoreName parameters are used by metadata that enables built-in filtering, 
+        // a feature currently exclusive to MongoDB
+        if (this.beforeDate) {
+            params.lastModified = {
+                lt: this.beforeDate,
+            };
+        }
+
+        if (this.excludedDataStoreName) {
+            params.dataStoreName = {
+                ne: this.excludedDataStoreName,
+            }
+        }
+
+        return params;
+    }
+
+    /**
+     * Parses the stringified entry's value.
+     * @param s - sringified value
+     * @return - undefined if parsing fails, otherwise it contains the parsed value.
+     */
+    _parse(s) {
+        let p;
+        try {
+            p = JSON.parse(s);
+        } catch (e: any) {
+            this.logger.warn(
+                'Could not parse Object Metadata while listing',
+                { err: e.toString() });
+        }
+        return p;
+    }
+
+    /**
+     * check if the max keys count has been reached and set the
+     * final state of the result if it is the case
+     *
+     * specialized implementation on DelimiterCurrent to also check
+     * the number of scanned keys
+     *
+     * @return {Boolean} - indicates if the iteration has to stop
+     */
+    _reachedMaxKeys(): boolean {
+        if (this.maxScannedLifecycleListingEntries && this.scannedKeys >= this.maxScannedLifecycleListingEntries) {
+            this.IsTruncated = true;
+            this.logger.info('listing stopped due to reaching the maximum scanned entries limit',
+                {
+                    maxScannedLifecycleListingEntries: this.maxScannedLifecycleListingEntries,
+                    scannedKeys: this.scannedKeys,
+                });
+            return true;
+        }
+        return super._reachedMaxKeys();
+    }
+
+    addContents(key, value) {
+        ++this.scannedKeys;
+        const parsedValue = this._parse(value);
+        // if parsing fails, skip the key.
+        if (parsedValue) {
+            const lastModified = parsedValue['last-modified'];
+            const dataStoreName = parsedValue.dataStoreName;
+            // We then check if the current version is older than the "beforeDate" and
+            // "excludedDataStoreName" is not specified or if specified and the data store name is different.
+            if ((!this.beforeDate || (lastModified && lastModified < this.beforeDate)) &&
+                (!this.excludedDataStoreName || dataStoreName !== this.excludedDataStoreName)) {
+                super.addContents(key, value);
+            }
+            // In the event of a timeout occurring before any content is added,
+            // NextMarker is updated even if the object is not eligible.
+            // It minimizes the amount of data that the client needs to re-process if the request times out.
+            this.nextMarker = key;
+        }
+    }
+
+    result(): object {
+        const result: ResultObject = {
+            Contents: this.Contents,
+            IsTruncated: this.IsTruncated,
+        };
+
+        if (this.IsTruncated) {
+            result.NextMarker = this.nextMarker;
+        }
+
+        return result;
+    }
+}
+module.exports = { DelimiterCurrent };

lib/algos/list/delimiterMaster.ts

@@ -0,0 +1,620 @@
+import {
+    Delimiter,
+    FilterState,
+    FilterReturnValue,
+    DelimiterFilterStateId,
+    DelimiterFilterState_NotSkipping,
+    DelimiterFilterState_SkippingPrefix,
+    ResultObject,
+} from './delimiter';
+const Version = require('../../versioning/Version').Version;
+const VSConst = require('../../versioning/constants').VersioningConstants;
+const { BucketVersioningKeyFormat } = VSConst;
+const { FILTER_ACCEPT, FILTER_SKIP, FILTER_END, SKIP_NONE, inc } = require('./tools');
+
+import { GapSetEntry } from '../cache/GapSet';
+import { GapCacheInterface } from '../cache/GapCache';
+
+const VID_SEP = VSConst.VersionId.Separator;
+const { DbPrefixes } = VSConst;
+
+export const enum DelimiterMasterFilterStateId {
+    SkippingVersionsV0 = 101,
+    WaitVersionAfterPHDV0 = 102,
+    SkippingGapV0 = 103,
+};
+
+interface DelimiterMasterFilterState_SkippingVersionsV0 extends FilterState {
+    id: DelimiterMasterFilterStateId.SkippingVersionsV0,
+    masterKey: string,
+};
+
+interface DelimiterMasterFilterState_WaitVersionAfterPHDV0 extends FilterState {
+    id: DelimiterMasterFilterStateId.WaitVersionAfterPHDV0,
+    masterKey: string,
+};
+
+interface DelimiterMasterFilterState_SkippingGapV0 extends FilterState {
+    id: DelimiterMasterFilterStateId.SkippingGapV0,
+};
+
+export const enum GapCachingState {
+    NoGapCache = 0, // there is no gap cache
+    UnknownGap = 1, // waiting for a cache lookup
+    GapLookupInProgress = 2, // asynchronous gap lookup in progress
+    GapCached = 3, // an upcoming or already skippable gap is cached
+    NoMoreGap = 4, // the cache doesn't have any more gaps inside the listed range
+};
+
+type GapCachingInfo_NoGapCache = {
+    state: GapCachingState.NoGapCache;
+};
+
+type GapCachingInfo_NoCachedGap = {
+    state: GapCachingState.UnknownGap
+        | GapCachingState.GapLookupInProgress
+    gapCache: GapCacheInterface;
+};
+
+type GapCachingInfo_GapCached = {
+    state: GapCachingState.GapCached;
+    gapCache: GapCacheInterface;
+    gapCached: GapSetEntry;
+};
+
+type GapCachingInfo_NoMoreGap = {
+    state: GapCachingState.NoMoreGap;
+};
+
+type GapCachingInfo = GapCachingInfo_NoGapCache
+    | GapCachingInfo_NoCachedGap
+    | GapCachingInfo_GapCached
+    | GapCachingInfo_NoMoreGap;
+
+
+export const enum GapBuildingState {
+    Disabled = 0, // no gap cache or no gap building needed (e.g. in V1 versioning format)
+    NotBuilding = 1, // not currently building a gap (i.e. not listing within a gap)
+    Building = 2, // currently building a gap (i.e. listing within a gap)
+    Expired = 3, // not allowed to build due to exposure delay timeout
+};
+
+type GapBuildingInfo_NothingToBuild = {
+    state: GapBuildingState.Disabled | GapBuildingState.Expired;
+};
+
+type GapBuildingParams = {
+    /**
+     * minimum weight for a gap to be created in the cache
+     */
+    minGapWeight: number;
+    /**
+     * trigger a cache setGap() call every N skippable keys
+     */
+    triggerSaveGapWeight: number;
+    /**
+     * timestamp to assess whether we're still inside the validity period to
+     * be allowed to build gaps
+     */
+    initTimestamp: number;
+};
+
+type GapBuildingInfo_NotBuilding = {
+    state: GapBuildingState.NotBuilding;
+    gapCache: GapCacheInterface;
+    params: GapBuildingParams;
+};
+
+type GapBuildingInfo_Building = {
+    state: GapBuildingState.Building;
+    gapCache: GapCacheInterface;
+    params: GapBuildingParams;
+    /**
+     * Gap currently being created
+     */
+    gap: GapSetEntry;
+    /**
+     * total current weight of the gap being created
+     */
+    gapWeight: number;
+};
+
+type GapBuildingInfo = GapBuildingInfo_NothingToBuild
+    | GapBuildingInfo_NotBuilding
+    | GapBuildingInfo_Building;
+
+/**
+ * Handle object listing with parameters. This extends the base class Delimiter
+ * to return the raw master versions of existing objects.
+ */
+export class DelimiterMaster extends Delimiter {
+
+    _gapCaching: GapCachingInfo;
+    _gapBuilding: GapBuildingInfo;
+    _refreshedBuildingParams: GapBuildingParams | null;
+
+    /**
+     * Delimiter listing of master versions.
+     * @param {Object}  parameters            - listing parameters
+     * @param {String}  [parameters.delimiter]  - delimiter per amazon format
+     * @param {String}  [parameters.prefix]     - prefix per amazon format
+     * @param {String}  [parameters.marker]     - marker per amazon format
+     * @param {Number}  [parameters.maxKeys]    - number of keys to list
+     * @param {Boolean} [parameters.v2]         - indicates whether v2 format
+     * @param {String}  [parameters.startAfter] - marker per amazon v2 format
+     * @param {String}  [parameters.continuationToken] - obfuscated amazon token
+     * @param {RequestLogger} logger            - The logger of the request
+     * @param {String}  [vFormat="v0"]          - versioning key format
+     */
+    constructor(parameters, logger, vFormat?: string) {
+        super(parameters, logger, vFormat);
+
+        if (this.vFormat === BucketVersioningKeyFormat.v0) {
+            // override Delimiter's implementation of NotSkipping for
+            // DelimiterMaster logic (skipping versions and special
+            // handling of delete markers and PHDs)
+            this.setKeyHandler(
+                DelimiterFilterStateId.NotSkipping,
+                this.keyHandler_NotSkippingPrefixNorVersionsV0.bind(this));
+
+            // add extra state handlers specific to DelimiterMaster with v0 format
+            this.setKeyHandler(
+                DelimiterMasterFilterStateId.SkippingVersionsV0,
+                this.keyHandler_SkippingVersionsV0.bind(this));
+
+            this.setKeyHandler(
+                DelimiterMasterFilterStateId.WaitVersionAfterPHDV0,
+                this.keyHandler_WaitVersionAfterPHDV0.bind(this));
+
+            this.setKeyHandler(
+                DelimiterMasterFilterStateId.SkippingGapV0,
+                this.keyHandler_SkippingGapV0.bind(this));
+
+            if (this.marker) {
+                // distinct initial state to include some special logic
+                // before the first master key is found that does not have
+                // to be checked afterwards
+                this.state = <DelimiterMasterFilterState_SkippingVersionsV0> {
+                    id: DelimiterMasterFilterStateId.SkippingVersionsV0,
+                    masterKey: this.marker,
+                };
+            } else {
+                this.state = <DelimiterFilterState_NotSkipping> {
+                    id: DelimiterFilterStateId.NotSkipping,
+                };
+            }
+        } else {
+            // save base implementation of the `NotSkipping` state in
+            // Delimiter before overriding it with ours, to be able to call it from there
+            this.keyHandler_NotSkipping_Delimiter = this.keyHandlers[DelimiterFilterStateId.NotSkipping];
+            this.setKeyHandler(
+                DelimiterFilterStateId.NotSkipping,
+                this.keyHandler_NotSkippingPrefixNorVersionsV1.bind(this));
+        }
+        // in v1, we can directly use Delimiter's implementation,
+        // which is already set to the proper state
+
+        // default initialization of the gap cache and building states, can be
+        // set by refreshGapCache()
+        this._gapCaching = {
+            state: GapCachingState.NoGapCache,
+        };
+        this._gapBuilding = {
+            state: GapBuildingState.Disabled,
+        };
+        this._refreshedBuildingParams = null;
+    }
+
+    /**
+     * Get the validity period left before a refresh of the gap cache is needed
+     * to continue building new gaps.
+     *
+     * @return {number|null} one of:
+     * - the remaining time in milliseconds in which gaps can be added to the
+     *   cache before a call to refreshGapCache() is required
+     * - or 0 if there is no time left and a call to refreshGapCache() is required
+     *   to resume caching gaps
+     * - or null if refreshing the cache is never needed (because the gap cache
+     *   is either not available or not used)
+     */
+    getGapBuildingValidityPeriodMs(): number | null {
+        let gapBuilding;
+        switch (this._gapBuilding.state) {
+        case GapBuildingState.Disabled:
+            return null;
+        case GapBuildingState.Expired:
+            return 0;
+        case GapBuildingState.NotBuilding:
+            gapBuilding = <GapBuildingInfo_NotBuilding> this._gapBuilding;
+            break;
+        case GapBuildingState.Building:
+            gapBuilding = <GapBuildingInfo_Building> this._gapBuilding;
+            break;
+        }
+        const { gapCache, params } = gapBuilding;
+        const elapsedTime = Date.now() - params.initTimestamp;
+        return Math.max(gapCache.exposureDelayMs - elapsedTime, 0);
+    }
+
+    /**
+     * Refresh the gaps caching logic (gaps are series of current delete markers
+     * in V0 bucket metadata format). It has two effects:
+     *
+     * - starts exposing existing and future gaps from the cache to efficiently
+     *   skip over series of current delete markers that have been seen and cached
+     *   earlier
+     *
+     * - enables building and caching new gaps (or extend existing ones), for a
+     *   limited time period defined by the `gapCacheProxy.exposureDelayMs` value
+     *   in milliseconds. To refresh the validity period and resume building and
+     *   caching new gaps, one must restart a new listing from the database (starting
+     *   at the current listing key, included), then call refreshGapCache() again.
+     *
+     * @param {GapCacheInterface} gapCacheProxy - API proxy to the gaps cache
+     *   (the proxy should handle prefixing object keys with the bucket name)
+     * @param {number} [minGapWeight=100] - minimum weight of a gap for it to be
+     *   added in the cache
+     * @param {number} [triggerSaveGapWeight] - cumulative weight to wait for
+     *   before saving the current building gap. Cannot be greater than
+     *   `gapCacheProxy.maxGapWeight` (the value is thresholded to `maxGapWeight`
+     *   otherwise). Defaults to `gapCacheProxy.maxGapWeight / 2`.
+     * @return {undefined}
+     */
+    refreshGapCache(
+        gapCacheProxy: GapCacheInterface,
+        minGapWeight?: number,
+        triggerSaveGapWeight?: number
+    ): void {
+        if (this.vFormat !== BucketVersioningKeyFormat.v0) {
+            return;
+        }
+        if (this._gapCaching.state === GapCachingState.NoGapCache) {
+            this._gapCaching = {
+                state: GapCachingState.UnknownGap,
+                gapCache: gapCacheProxy,
+            };
+        }
+        const refreshedBuildingParams: GapBuildingParams = {
+            minGapWeight: minGapWeight || 100,
+            triggerSaveGapWeight: triggerSaveGapWeight
+                || Math.trunc(gapCacheProxy.maxGapWeight / 2),
+            initTimestamp: Date.now(),
+        };
+        if (this._gapBuilding.state === GapBuildingState.Building) {
+            // refreshed params will be applied as soon as the current building gap is saved
+            this._refreshedBuildingParams = refreshedBuildingParams;
+        } else {
+            this._gapBuilding = {
+                state: GapBuildingState.NotBuilding,
+                gapCache: gapCacheProxy,
+                params: refreshedBuildingParams,
+            };
+        }
+    }
+
+    /**
+     * Trigger a lookup of the closest upcoming or already skippable gap.
+     *
+     * @param {string} fromKey - lookup a gap not before 'fromKey'
+     * @return {undefined} - the lookup is asynchronous and its
+     * response is handled inside this function
+     */
+    _triggerGapLookup(gapCaching: GapCachingInfo_NoCachedGap, fromKey: string): void {
+        this._gapCaching = {
+            state: GapCachingState.GapLookupInProgress,
+            gapCache: gapCaching.gapCache,
+        };
+        const maxKey = this.prefix ? inc(this.prefix) : undefined;
+        gapCaching.gapCache.lookupGap(fromKey, maxKey).then(_gap => {
+            const gap = <GapSetEntry | null> _gap;
+            if (gap) {
+                this._gapCaching = {
+                    state: GapCachingState.GapCached,
+                    gapCache: gapCaching.gapCache,
+                    gapCached: gap,
+                };
+            } else {
+                this._gapCaching = {
+                    state: GapCachingState.NoMoreGap,
+                };
+            }
+        });
+    }
+
+    _checkGapOnMasterDeleteMarker(key: string): FilterReturnValue {
+        switch (this._gapBuilding.state) {
+        case GapBuildingState.Disabled:
+        case GapBuildingState.Expired:
+            break;
+        case GapBuildingState.NotBuilding:
+            this._createBuildingGap(key, 1);
+            break;
+        case GapBuildingState.Building:
+            this._updateBuildingGap(key);
+            break;
+        }
+        if (this._gapCaching.state === GapCachingState.GapCached) {
+            const { gapCached } = this._gapCaching;
+            if (key >= gapCached.firstKey) {
+                if (key <= gapCached.lastKey) {
+                    // we are inside the last looked up cached gap: transition to
+                    // 'SkippingGapV0' state
+                    this.setState(<DelimiterMasterFilterState_SkippingGapV0> {
+                        id: DelimiterMasterFilterStateId.SkippingGapV0,
+                    });
+                    // cut the current gap before skipping, it will be merged or
+                    // chained with the existing one (depending on its weight)
+                    if (this._gapBuilding.state === GapBuildingState.Building) {
+                        // substract 1 from the weight because we are going to chain this gap,
+                        // which has an overlap of one key.
+                        this._gapBuilding.gap.weight -= 1;
+                        this._cutBuildingGap();
+                    }
+                    return FILTER_SKIP;
+                }
+                // as we are past the cached gap, we will need another lookup
+                this._gapCaching = {
+                    state: GapCachingState.UnknownGap,
+                    gapCache: this._gapCaching.gapCache,
+                };
+            }
+        }
+        if (this._gapCaching.state === GapCachingState.UnknownGap) {
+            this._triggerGapLookup(this._gapCaching, key);
+        }
+        return FILTER_ACCEPT;
+    }
+
+    filter_onNewMasterKeyV0(key: string, value: string): FilterReturnValue {
+        // if this master key is a delete marker, accept it without
+        // adding the version to the contents
+        if (Version.isDeleteMarker(value)) {
+            // update the state to start skipping versions of the new master key
+            this.setState(<DelimiterMasterFilterState_SkippingVersionsV0> {
+                id: DelimiterMasterFilterStateId.SkippingVersionsV0,
+                masterKey: key,
+            });
+            return this._checkGapOnMasterDeleteMarker(key);
+        }
+        if (Version.isPHD(value)) {
+            // master version is a PHD version: wait for the first
+            // following version that will be considered as the actual
+            // master key
+            this.setState(<DelimiterMasterFilterState_WaitVersionAfterPHDV0> {
+                id: DelimiterMasterFilterStateId.WaitVersionAfterPHDV0,
+                masterKey: key,
+            });
+            return FILTER_ACCEPT;
+        }
+        // cut the current gap as soon as a non-deleted entry is seen
+        this._cutBuildingGap();
+
+        if (key.startsWith(DbPrefixes.Replay)) {
+            // skip internal replay prefix entirely
+            this.setState(<DelimiterFilterState_SkippingPrefix> {
+                id: DelimiterFilterStateId.SkippingPrefix,
+                prefix: DbPrefixes.Replay,
+            });
+            return FILTER_SKIP;
+        }
+        if (this._reachedMaxKeys()) {
+            return FILTER_END;
+        }
+
+        const commonPrefix = this.addCommonPrefixOrContents(key, value);
+        if (commonPrefix) {
+            // transition into SkippingPrefix state to skip all following keys
+            // while they start with the same prefix
+            this.setState(<DelimiterFilterState_SkippingPrefix> {
+                id: DelimiterFilterStateId.SkippingPrefix,
+                prefix: commonPrefix,
+            });
+            return FILTER_ACCEPT;
+        }
+        // update the state to start skipping versions of the new master key
+        this.setState(<DelimiterMasterFilterState_SkippingVersionsV0> {
+            id: DelimiterMasterFilterStateId.SkippingVersionsV0,
+            masterKey: key,
+        });
+        return FILTER_ACCEPT;
+    }
+
+    keyHandler_NotSkippingPrefixNorVersionsV0(key: string, value: string): FilterReturnValue {
+        return this.filter_onNewMasterKeyV0(key, value);
+    }
+
+    filter_onNewMasterKeyV1(key: string, value: string): FilterReturnValue {
+        // if this master key is a delete marker, accept it without
+        // adding the version to the contents
+        if (Version.isDeleteMarker(value)) {
+            return FILTER_ACCEPT;
+        }
+        // use base Delimiter's implementation
+        return this.keyHandler_NotSkipping_Delimiter(key, value);
+    }
+
+    keyHandler_NotSkippingPrefixNorVersionsV1(key: string, value: string): FilterReturnValue {
+        return this.filter_onNewMasterKeyV1(key, value);
+    }
+
+    keyHandler_SkippingVersionsV0(key: string, value: string): FilterReturnValue {
+        /* In the SkippingVersionsV0 state, skip all version keys
+         * (<key><versionIdSeparator><version>) */
+        const versionIdIndex = key.indexOf(VID_SEP);
+        if (versionIdIndex !== -1) {
+            // version keys count in the building gap weight because they must
+            // also be listed until skipped
+            if (this._gapBuilding.state === GapBuildingState.Building) {
+                this._updateBuildingGap(key);
+            }
+            return FILTER_SKIP;
+        }
+        return this.filter_onNewMasterKeyV0(key, value);
+    }
+
+    keyHandler_WaitVersionAfterPHDV0(key: string, value: string): FilterReturnValue {
+        // After a PHD key is encountered, the next version key of the
+        // same object if it exists is the new master key, hence
+        // consider it as such and call 'onNewMasterKeyV0' (the test
+        // 'masterKey == phdKey' is probably redundant when we already
+        // know we have a versioned key, since all objects in v0 have
+        // a master key, but keeping it in doubt)
+        const { masterKey: phdKey } = <DelimiterMasterFilterState_WaitVersionAfterPHDV0> this.state;
+        const versionIdIndex = key.indexOf(VID_SEP);
+        if (versionIdIndex !== -1) {
+            const masterKey = key.slice(0, versionIdIndex);
+            if (masterKey === phdKey) {
+                return this.filter_onNewMasterKeyV0(masterKey, value);
+            }
+        }
+        return this.filter_onNewMasterKeyV0(key, value);
+    }
+
+    keyHandler_SkippingGapV0(key: string, value: string): FilterReturnValue {
+        const { gapCache, gapCached } = <GapCachingInfo_GapCached> this._gapCaching;
+        if (key <= gapCached.lastKey) {
+            return FILTER_SKIP;
+        }
+        this._gapCaching = {
+            state: GapCachingState.UnknownGap,
+            gapCache,
+        };
+        this.setState(<DelimiterMasterFilterState_SkippingVersionsV0> {
+            id: DelimiterMasterFilterStateId.SkippingVersionsV0,
+        });
+        // Start a gap with weight=0 from the latest skippable key. This will
+        // allow to extend the gap just skipped with a chained gap in case
+        // other delete markers are seen after the existing gap is skipped.
+        this._createBuildingGap(gapCached.lastKey, 0, gapCached.weight);
+
+        return this.handleKey(key, value);
+    }
+
+    skippingBase(): string | undefined {
+        switch (this.state.id) {
+        case DelimiterMasterFilterStateId.SkippingVersionsV0:
+            const { masterKey } = <DelimiterMasterFilterState_SkippingVersionsV0> this.state;
+            return masterKey + inc(VID_SEP);
+
+        case DelimiterMasterFilterStateId.SkippingGapV0:
+            const { gapCached } = <GapCachingInfo_GapCached> this._gapCaching;
+            return gapCached.lastKey;
+
+        default:
+            return super.skippingBase();
+        }
+    }
+
+    result(): ResultObject {
+        this._cutBuildingGap();
+        return super.result();
+    }
+
+    _checkRefreshedBuildingParams(params: GapBuildingParams): GapBuildingParams {
+        if (this._refreshedBuildingParams) {
+            const newParams = this._refreshedBuildingParams;
+            this._refreshedBuildingParams = null;
+            return newParams;
+        }
+        return params;
+    }
+
+    /**
+     * Save the gap being built if allowed (i.e. still within the
+     * allocated exposure time window).
+     *
+     * @return {boolean} - true if the gap was saved, false if we are
+     * outside the allocated exposure time window.
+     */
+    _saveBuildingGap(): boolean {
+        const { gapCache, params, gap, gapWeight } =
+              <GapBuildingInfo_Building> this._gapBuilding;
+        const totalElapsed = Date.now() - params.initTimestamp;
+        if (totalElapsed >= gapCache.exposureDelayMs) {
+            this._gapBuilding = {
+                state: GapBuildingState.Expired,
+            };
+            this._refreshedBuildingParams = null;
+            return false;
+        }
+        const { firstKey, lastKey, weight } = gap;
+        gapCache.setGap(firstKey, lastKey, weight);
+        this._gapBuilding = {
+            state: GapBuildingState.Building,
+            gapCache,
+            params: this._checkRefreshedBuildingParams(params),
+            gap: {
+                firstKey: gap.lastKey,
+                lastKey: gap.lastKey,
+                weight: 0,
+            },
+            gapWeight,
+        };
+        return true;
+    }
+
+    /**
+     * Create a new gap to be extended afterwards
+     *
+     * @param {string} newKey - gap's first key
+     * @param {number} startWeight - initial weight of the building gap (usually 0 or 1)
+     * @param {number} [cachedWeight] - if continuing a cached gap, weight of the existing
+     *   cached portion
+     * @return {undefined}
+     */
+    _createBuildingGap(newKey: string, startWeight: number, cachedWeight?: number): void {
+        if (this._gapBuilding.state === GapBuildingState.NotBuilding) {
+            const { gapCache, params } = <GapBuildingInfo_NotBuilding> this._gapBuilding;
+            this._gapBuilding = {
+                state: GapBuildingState.Building,
+                gapCache,
+                params: this._checkRefreshedBuildingParams(params),
+                gap: {
+                    firstKey: newKey,
+                    lastKey: newKey,
+                    weight: startWeight,
+                },
+                gapWeight: (cachedWeight || 0) + startWeight,
+            };
+        }
+    }
+
+    _updateBuildingGap(newKey: string): void {
+        const gapBuilding = <GapBuildingInfo_Building> this._gapBuilding;
+        const { params, gap } = gapBuilding;
+        gap.lastKey = newKey;
+        gap.weight += 1;
+        gapBuilding.gapWeight += 1;
+        // the GapCache API requires updating a gap regularly because it can only split
+        // it once per update, by the known last key. In practice the default behavior
+        // is to trigger an update after a number of keys that is half the maximum weight.
+        // It is also useful for other listings to benefit from the cache sooner.
+        if (gapBuilding.gapWeight >= params.minGapWeight &&
+            gap.weight >= params.triggerSaveGapWeight) {
+            this._saveBuildingGap();
+        }
+    }
+
+    _cutBuildingGap(): void {
+        if (this._gapBuilding.state === GapBuildingState.Building) {
+            let gapBuilding = <GapBuildingInfo_Building> this._gapBuilding;
+            let { gapCache, params, gap, gapWeight } = gapBuilding;
+            // only set gaps that are significant enough in weight and
+            // with a non-empty extension
+            if (gapWeight >= params.minGapWeight && gap.weight > 0) {
+                // we're done if we were not allowed to save the gap
+                if (!this._saveBuildingGap()) {
+                    return;
+                }
+                // params may have been refreshed, reload them
+                gapBuilding = <GapBuildingInfo_Building> this._gapBuilding;
+                params = gapBuilding.params;
+            }
+            this._gapBuilding = {
+                state: GapBuildingState.NotBuilding,
+                gapCache,
+                params,
+            };
+        }
+    }
+}

lib/algos/list/delimiterNonCurrent.js

@@ -0,0 +1,202 @@
+const { DelimiterVersions } = require('./delimiterVersions');
+const { FILTER_END, FILTER_SKIP } = require('./tools');
+
+const TRIM_METADATA_MIN_BLOB_SIZE = 10000;
+
+/**
+ * Handle object listing with parameters. This extends the base class DelimiterVersions
+ * to return the raw non-current versions objects.
+ */
+class DelimiterNonCurrent extends DelimiterVersions {
+    /**
+     * Delimiter listing of non-current versions.
+     * @param {Object}  parameters                  - listing parameters
+     * @param {String}  parameters.keyMarker        - key marker
+     * @param {String}  parameters.versionIdMarker  - version id marker
+     * @param {String}  parameters.beforeDate       - limit the response to keys with stale date older than beforeDate.
+     * “stale date” is the date on when a version becomes non-current.
+     * @param {Number} parameters.maxScannedLifecycleListingEntries - max number of entries to be scanned
+     * @param {String} parameters.excludedDataStoreName - exclude dataStoreName matches from the versions
+     * @param {RequestLogger} logger                - The logger of the request
+     * @param {String} [vFormat]                    - versioning key format
+     */
+    constructor(parameters, logger, vFormat) {
+        super(parameters, logger, vFormat);
+
+        this.beforeDate = parameters.beforeDate;
+        this.excludedDataStoreName = parameters.excludedDataStoreName;
+        this.maxScannedLifecycleListingEntries = parameters.maxScannedLifecycleListingEntries;
+
+        // internal state
+        this.prevKey = null;
+        this.staleDate = null;
+
+        this.scannedKeys = 0;
+    }
+
+    getLastModified(value) {
+        let lastModified;
+        try {
+            const v = JSON.parse(value);
+            lastModified = v['last-modified'];
+        } catch (e) {
+            this.logger.warn('could not parse Object Metadata while listing',
+                {
+                    method: 'getLastModified',
+                    err: e.toString(),
+                });
+        }
+        return lastModified;
+    }
+
+    // Overwrite keyHandler_SkippingVersions to include the last version from the previous listing.
+    // The creation (last-modified) date of this version will be the stale date for the following version.
+    // eslint-disable-next-line camelcase
+    keyHandler_SkippingVersions(key, versionId, value) {
+        if (key === this.keyMarker) {
+            // since the nonversioned key equals the marker, there is
+            // necessarily a versionId in this key
+            const _versionId = versionId;
+            if (_versionId < this.versionIdMarker) {
+                // skip all versions until marker
+                return FILTER_SKIP;
+            }
+        }
+        this.setState({
+            id: 1 /* NotSkipping */,
+        });
+        return this.handleKey(key, versionId, value);
+    }
+
+    filter(obj) {
+        if (this.maxScannedLifecycleListingEntries && this.scannedKeys >= this.maxScannedLifecycleListingEntries) {
+            this.IsTruncated = true;
+            this.logger.info('listing stopped due to reaching the maximum scanned entries limit',
+                {
+                    maxScannedLifecycleListingEntries: this.maxScannedLifecycleListingEntries,
+                    scannedKeys: this.scannedKeys,
+                });
+            return FILTER_END;
+        }
+        ++this.scannedKeys;
+        return super.filter(obj);
+    }
+
+    /**
+     * NOTE: Each version of a specific key is sorted from the latest to the oldest
+     * thanks to the way version ids are generated.
+     * DESCRIPTION: Skip the version if it represents the master key, but keep its last-modified date in memory,
+     * which will be the stale date of the following version.
+     * The following version is pushed only:
+     * - if the "stale date" (picked up from the previous version) is available (JSON.parse has not failed),
+     * - if "beforeDate" is not specified or if specified and the "stale date" is older.
+     * - if "excludedDataStoreName" is not specified or if specified and the data store name is different
+     * The in-memory "stale date" is then updated with the version's last-modified date to be used for
+     * the following version.
+     * The process stops and returns the available results if either:
+     * - no more metadata key is left to be processed
+     * - the listing reaches the maximum number of key to be returned
+     * - the internal timeout is reached
+     *  @param {String} key   - The key to add
+     *  @param {String} versionId - The version id
+     *  @param {String} value - The value of the key
+     *  @return {undefined}
+     */
+    addVersion(key, versionId, value) {
+        this.nextKeyMarker = key;
+        this.nextVersionIdMarker = versionId;
+
+        // Skip the version if it represents the non-current version, but keep its last-modified date,
+        // which will be the stale date of the following version.
+        const isCurrentVersion = key !== this.prevKey;
+        if (isCurrentVersion) {
+            this.staleDate = this.getLastModified(value);
+            this.prevKey = key;
+            return;
+        }
+
+        // The following version is pushed only:
+        // - if the "stale date" (picked up from the previous version) is available (JSON.parse has not failed),
+        // - if "beforeDate" is not specified or if specified and the "stale date" is older.
+        // - if "excludedDataStoreName" is not specified or if specified and the data store name is different
+        let lastModified;
+        if (this.staleDate && (!this.beforeDate || this.staleDate < this.beforeDate)) {
+            const parsedValue = this._parse(value);
+            // if parsing fails, skip the key.
+            if (parsedValue) {
+                const dataStoreName = parsedValue.dataStoreName;
+                lastModified = parsedValue['last-modified'];
+                if (!this.excludedDataStoreName || dataStoreName !== this.excludedDataStoreName) {
+                    const s = this._stringify(parsedValue, this.staleDate);
+                    // check that _stringify succeeds to only push objects with a defined staleDate.
+                    if (s) {
+                        this.Versions.push({ key, value: s });
+                        ++this.keys;
+                    }
+                }
+            }
+        }
+
+        // The in-memory "stale date" is then updated with the version's last-modified date to be used for
+        // the following version.
+        this.staleDate = lastModified || this.getLastModified(value);
+
+        return;
+    }
+
+    /**
+     * Parses the stringified entry's value and remove the location property if too large.
+     * @param {string} s - sringified value
+     * @return {object} p - undefined if parsing fails, otherwise it contains the parsed value.
+     */
+    _parse(s) {
+        let p;
+        try {
+            p = JSON.parse(s);
+            if (s.length >= TRIM_METADATA_MIN_BLOB_SIZE) {
+                delete p.location;
+            }
+        } catch (e) {
+            this.logger.warn('Could not parse Object Metadata while listing', {
+                method: 'DelimiterNonCurrent._parse',
+                err: e.toString(),
+            });
+        }
+        return p;
+    }
+
+    _stringify(parsedMD, staleDate) {
+        const p = parsedMD;
+        let s = undefined;
+        p.staleDate = staleDate;
+        try {
+            s = JSON.stringify(p);
+        } catch (e) {
+            this.logger.warn('could not stringify Object Metadata while listing', {
+                method: 'DelimiterNonCurrent._stringify',
+                err: e.toString(),
+            });
+        }
+        return s;
+    }
+
+    result() {
+        const { Versions, IsTruncated, NextKeyMarker, NextVersionIdMarker } = super.result();
+
+        const result = {
+            Contents: Versions,
+            IsTruncated,
+        };
+
+        if (NextKeyMarker) {
+            result.NextKeyMarker = NextKeyMarker;
+        }
+
+        if (NextVersionIdMarker) {
+            result.NextVersionIdMarker = NextVersionIdMarker;
+        }
+
+        return result;
+    }
+}
+module.exports = { DelimiterNonCurrent };

lib/algos/list/delimiterOrphanDeleteMarker.js

@@ -0,0 +1,204 @@
+const DelimiterVersions = require('./delimiterVersions').DelimiterVersions;
+const { FILTER_END } = require('./tools');
+const TRIM_METADATA_MIN_BLOB_SIZE = 10000;
+/**
+ * Handle object listing with parameters. This extends the base class DelimiterVersions
+ * to return the orphan delete markers. Orphan delete markers are also
+ * refered as expired object delete marker.
+ * They are delete marker with zero noncurrent versions.
+ */
+class DelimiterOrphanDeleteMarker extends DelimiterVersions {
+    /**
+     * Delimiter listing of orphan delete markers.
+     * @param {Object}  parameters            - listing parameters
+     * @param {String}  parameters.beforeDate - limit the response to keys older than beforeDate
+     * @param {Number} parameters.maxScannedLifecycleListingEntries - max number of entries to be scanned
+     * @param {RequestLogger} logger          - The logger of the request
+     * @param {String} [vFormat]              - versioning key format
+     */
+    constructor(parameters, logger, vFormat) {
+        const {
+            marker,
+            maxKeys,
+            prefix,
+            beforeDate,
+            maxScannedLifecycleListingEntries,
+        } = parameters;
+
+        const versionParams = {
+            // The orphan delete marker logic uses the term 'marker' instead of 'keyMarker',
+            // as the latter could suggest the presence of a 'versionIdMarker'.
+            keyMarker: marker,
+            maxKeys,
+            prefix,
+        };
+        super(versionParams, logger, vFormat);
+
+        this.maxScannedLifecycleListingEntries = maxScannedLifecycleListingEntries;
+        this.beforeDate = beforeDate;
+        // this.prevKeyName is used as a marker for the next listing when the current one reaches its entry limit.
+        // We cannot rely on this.keyName, as it contains the name of the current key.
+        // In the event of a listing interruption due to reaching the maximum scanned entries,
+        // relying on this.keyName would cause the next listing to skip the current key because S3 starts
+        // listing after the marker.
+        this.prevKeyName = null;
+        this.keyName = null;
+        this.value = null;
+        this.scannedKeys = 0;
+    }
+
+    _reachedMaxKeys() {
+        if (this.keys >= this.maxKeys) {
+            return true;
+        }
+        return false;
+    }
+
+    _addOrphan() {
+        const parsedValue = this._parse(this.value);
+        // if parsing fails, skip the key.
+        if (parsedValue) {
+            const lastModified = parsedValue['last-modified'];
+            const isDeleteMarker = parsedValue.isDeleteMarker;
+            // We then check if the orphan version is a delete marker and if it is older than the "beforeDate"
+            if ((!this.beforeDate || (lastModified && lastModified < this.beforeDate)) && isDeleteMarker) {
+                // Prefer returning an untrimmed data rather than stopping the service in case of parsing failure.
+                const s = this._stringify(parsedValue) || this.value;
+                this.Versions.push({ key: this.keyName, value: s });
+                this.nextKeyMarker = this.keyName;
+                ++this.keys;
+            }
+        }
+    }
+
+    /**
+     * Parses the stringified entry's value and remove the location property if too large.
+     * @param {string} s - sringified value
+     * @return {object} p - undefined if parsing fails, otherwise it contains the parsed value.
+     */
+    _parse(s) {
+        let p;
+        try {
+            p = JSON.parse(s);
+            if (s.length >= TRIM_METADATA_MIN_BLOB_SIZE) {
+                delete p.location;
+            }
+        } catch (e) {
+            this.logger.warn('Could not parse Object Metadata while listing', {
+                method: 'DelimiterOrphanDeleteMarker._parse',
+                err: e.toString(),
+            });
+        }
+        return p;
+    }
+
+    _stringify(value) {
+        const p = value;
+        let s = undefined;
+        try {
+            s = JSON.stringify(p);
+        } catch (e) {
+            this.logger.warn('could not stringify Object Metadata while listing',
+                {
+                    method: 'DelimiterOrphanDeleteMarker._stringify',
+                    err: e.toString(),
+                });
+        }
+        return s;
+    }
+    /**
+     * The purpose of _isMaxScannedEntriesReached is to restrict the number of scanned entries,
+     * thus controlling resource overhead (CPU...).
+     * @return {boolean} isMaxScannedEntriesReached - true if the maximum limit on the number
+     * of entries scanned has been reached, false otherwise.
+    */
+    _isMaxScannedEntriesReached() {
+        return this.maxScannedLifecycleListingEntries && this.scannedKeys >= this.maxScannedLifecycleListingEntries;
+    }
+
+    filter(obj) {
+        if (this._isMaxScannedEntriesReached()) {
+            this.nextKeyMarker = this.prevKeyName;
+            this.IsTruncated = true;
+            this.logger.info('listing stopped due to reaching the maximum scanned entries limit',
+                {
+                    maxScannedLifecycleListingEntries: this.maxScannedLifecycleListingEntries,
+                    scannedKeys: this.scannedKeys,
+                });
+            return FILTER_END;
+        }
+        ++this.scannedKeys;
+        return super.filter(obj);
+    }
+
+    /**
+     * NOTE: Each version of a specific key is sorted from the latest to the oldest
+     * thanks to the way version ids are generated.
+     * DESCRIPTION: For a given key, the latest version is kept in memory since it is the current version.
+     * If the following version reference a new key, it means that the previous one was an orphan version.
+     * We then check if the orphan version is a delete marker and if it is older than the "beforeDate"
+     * The process stops and returns the available results if either:
+     * - no more metadata key is left to be processed
+     * - the listing reaches the maximum number of key to be returned
+     * - the internal timeout is reached
+     * NOTE: we cannot leverage MongoDB to list keys older than "beforeDate"
+     * because then we will not be able to assess its orphanage.
+     *  @param {String} key   - The object key.
+     * @param {String} versionId   - The object version id.
+     *  @param {String} value - The value of the key
+     *  @return {undefined}
+     */
+    addVersion(key, versionId, value) {
+        // For a given key, the youngest version is kept in memory since it represents the current version.
+        if (key !== this.keyName) {
+            // If this.value is defined, it means that <this.keyName, this.value> pair is "allowed" to be an orphan.
+            if (this.value) {
+                this._addOrphan();
+            }
+            this.prevKeyName = this.keyName;
+            this.keyName = key;
+            this.value = value;
+
+            return;
+        }
+
+        // If the key is not the current version, we can skip it in the next listing
+        // in the case where the current listing is interrupted due to reaching the maximum scanned entries.
+        this.prevKeyName = key;
+        this.keyName = key;
+        this.value = null;
+
+        return;
+    }
+
+    result() {
+        // Only check for remaining last orphan delete marker if the listing is not interrupted.
+        // This will help avoid false positives.
+        if (!this._isMaxScannedEntriesReached()) {
+            // The following check makes sure the last orphan delete marker is not forgotten.
+            if (this.keys < this.maxKeys) {
+                if (this.value) {
+                    this._addOrphan();
+                }
+            // The following make sure that if makeKeys is reached, isTruncated is set to true.
+            // We moved the "isTruncated" from _reachedMaxKeys to make sure we take into account the last entity
+            // if listing is truncated right before the last entity and the last entity is a orphan delete marker.
+            } else {
+                this.IsTruncated = this.maxKeys > 0;
+            }
+        }
+
+        const result = {
+            Contents: this.Versions,
+            IsTruncated: this.IsTruncated,
+        };
+
+        if (this.IsTruncated) {
+            result.NextMarker = this.nextKeyMarker;
+        }
+
+        return result;
+    }
+}
+
+module.exports = { DelimiterOrphanDeleteMarker };

lib/algos/list/delimiterVersions.ts

@@ -0,0 +1,535 @@
+'use strict'; // eslint-disable-line strict
+
+const Extension = require('./Extension').default;
+
+import {
+    FilterState,
+    FilterReturnValue,
+} from './delimiter';
+
+const Version = require('../../versioning/Version').Version;
+const VSConst = require('../../versioning/constants').VersioningConstants;
+const { inc, FILTER_END, FILTER_ACCEPT, FILTER_SKIP, SKIP_NONE } =
+    require('./tools');
+
+const VID_SEP = VSConst.VersionId.Separator;
+const { DbPrefixes, BucketVersioningKeyFormat } = VSConst;
+
+export const enum DelimiterVersionsFilterStateId {
+    NotSkipping = 1,
+    SkippingPrefix = 2,
+    SkippingVersions = 3,
+};
+
+export interface DelimiterVersionsFilterState_NotSkipping extends FilterState {
+    id: DelimiterVersionsFilterStateId.NotSkipping,
+};
+
+export interface DelimiterVersionsFilterState_SkippingPrefix extends FilterState {
+    id: DelimiterVersionsFilterStateId.SkippingPrefix,
+    prefix: string;
+};
+
+export interface DelimiterVersionsFilterState_SkippingVersions extends FilterState {
+    id: DelimiterVersionsFilterStateId.SkippingVersions,
+    gt: string;
+};
+
+type KeyHandler = (key: string, versionId: string | undefined, value: string) => FilterReturnValue;
+
+type ResultObject = {
+    CommonPrefixes: string[],
+    Versions: {
+        key: string;
+        value: string;
+        versionId: string;
+    }[];
+    IsTruncated: boolean;
+    Delimiter ?: string;
+    NextKeyMarker ?: string;
+    NextVersionIdMarker ?: string;
+};
+
+type GenMDParamsItem = {
+    gt ?: string,
+    gte ?: string,
+    lt ?: string,
+};
+
+/**
+ * Handle object listing with parameters
+ *
+ * @prop {String[]} CommonPrefixes     - 'folders' defined by the delimiter
+ * @prop {String[]} Contents           - 'files' to list
+ * @prop {Boolean} IsTruncated         - truncated listing flag
+ * @prop {String|undefined} NextMarker - marker per amazon format
+ * @prop {Number} keys                 - count of listed keys
+ * @prop {String|undefined} delimiter  - separator per amazon format
+ * @prop {String|undefined} prefix     - prefix per amazon format
+ * @prop {Number} maxKeys              - number of keys to list
+ */
+export class DelimiterVersions extends Extension {
+
+    state: FilterState;
+    keyHandlers: { [id: number]: KeyHandler };
+
+    constructor(parameters, logger, vFormat) {
+        super(parameters, logger);
+        // original listing parameters
+        this.delimiter = parameters.delimiter;
+        this.prefix = parameters.prefix;
+        this.maxKeys = parameters.maxKeys || 1000;
+        // specific to version listing
+        this.keyMarker = parameters.keyMarker;
+        this.versionIdMarker = parameters.versionIdMarker;
+        // internal state
+        this.masterKey = undefined;
+        this.masterVersionId = undefined;
+        this.nullKey = null;
+        this.vFormat = vFormat || BucketVersioningKeyFormat.v0;
+        // listing results
+        this.CommonPrefixes = [];
+        this.Versions = [];
+        this.IsTruncated = false;
+        this.nextKeyMarker = parameters.keyMarker;
+        this.nextVersionIdMarker = undefined;
+
+        this.keyHandlers = {};
+
+        Object.assign(this, {
+            [BucketVersioningKeyFormat.v0]: {
+                genMDParams: this.genMDParamsV0,
+                getObjectKey: this.getObjectKeyV0,
+                skipping: this.skippingV0,
+            },
+            [BucketVersioningKeyFormat.v1]: {
+                genMDParams: this.genMDParamsV1,
+                getObjectKey: this.getObjectKeyV1,
+                skipping: this.skippingV1,
+            },
+        }[this.vFormat]);
+
+        if (this.vFormat === BucketVersioningKeyFormat.v0) {
+            this.setKeyHandler(
+                DelimiterVersionsFilterStateId.NotSkipping,
+                this.keyHandler_NotSkippingV0.bind(this));
+        } else {
+            this.setKeyHandler(
+                DelimiterVersionsFilterStateId.NotSkipping,
+                this.keyHandler_NotSkippingV1.bind(this));
+        }
+        this.setKeyHandler(
+            DelimiterVersionsFilterStateId.SkippingPrefix,
+            this.keyHandler_SkippingPrefix.bind(this));
+
+        this.setKeyHandler(
+            DelimiterVersionsFilterStateId.SkippingVersions,
+            this.keyHandler_SkippingVersions.bind(this));
+
+        if (this.versionIdMarker) {
+            this.state = <DelimiterVersionsFilterState_SkippingVersions> {
+                id: DelimiterVersionsFilterStateId.SkippingVersions,
+                gt: `${this.keyMarker}${VID_SEP}${this.versionIdMarker}`,
+            };
+        } else {
+            this.state = <DelimiterVersionsFilterState_NotSkipping> {
+                id: DelimiterVersionsFilterStateId.NotSkipping,
+            };
+        }
+    }
+
+    genMDParamsV0() {
+        const params: GenMDParamsItem = {};
+        if (this.prefix) {
+            params.gte = this.prefix;
+            params.lt = inc(this.prefix);
+        }
+        if (this.keyMarker && this.delimiter) {
+            const commonPrefix = this.getCommonPrefix(this.keyMarker);
+            if (commonPrefix) {
+                const afterPrefix = inc(commonPrefix);
+                if (!params.gte || afterPrefix > params.gte) {
+                    params.gte = afterPrefix;
+                }
+            }
+        }
+        if (this.keyMarker && (!params.gte || this.keyMarker >= params.gte)) {
+            delete params.gte;
+            if (this.versionIdMarker) {
+                // start from the beginning of versions so we can
+                // check if there's a null key and fetch it
+                // (afterwards, we can skip the rest of versions until
+                // we reach versionIdMarker)
+                params.gte = `${this.keyMarker}${VID_SEP}`;
+            } else {
+                params.gt = `${this.keyMarker}${inc(VID_SEP)}`;
+            }
+        }
+        return params;
+    }
+
+    genMDParamsV1() {
+        // return an array of two listing params sets to ask for
+        // synchronized listing of M and V ranges
+        const v0Params: GenMDParamsItem = this.genMDParamsV0();
+        const mParams: GenMDParamsItem = {};
+        const vParams: GenMDParamsItem = {};
+        if (v0Params.gt) {
+            mParams.gt = `${DbPrefixes.Master}${v0Params.gt}`;
+            vParams.gt = `${DbPrefixes.Version}${v0Params.gt}`;
+        } else if (v0Params.gte) {
+            mParams.gte = `${DbPrefixes.Master}${v0Params.gte}`;
+            vParams.gte = `${DbPrefixes.Version}${v0Params.gte}`;
+        } else {
+            mParams.gte = DbPrefixes.Master;
+            vParams.gte = DbPrefixes.Version;
+        }
+        if (v0Params.lt) {
+            mParams.lt = `${DbPrefixes.Master}${v0Params.lt}`;
+            vParams.lt = `${DbPrefixes.Version}${v0Params.lt}`;
+        } else {
+            mParams.lt = inc(DbPrefixes.Master);
+            vParams.lt = inc(DbPrefixes.Version);
+        }
+        return [mParams, vParams];
+    }
+
+    /**
+     * check if the max keys count has been reached and set the
+     * final state of the result if it is the case
+     * @return {Boolean} - indicates if the iteration has to stop
+     */
+    _reachedMaxKeys(): boolean {
+        if (this.keys >= this.maxKeys) {
+            // In cases of maxKeys <= 0 -> IsTruncated = false
+            this.IsTruncated = this.maxKeys > 0;
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Used to synchronize listing of M and V prefixes by object key
+     *
+     * @param {object} masterObj object listed from first range
+     * returned by genMDParamsV1() (the master keys range)
+     * @param {object} versionObj object listed from second range
+     * returned by genMDParamsV1() (the version keys range)
+     * @return {number} comparison result:
+     *   * -1 if master key < version key
+     *   * 1 if master key > version key
+     */
+    compareObjects(masterObj, versionObj) {
+        const masterKey = masterObj.key.slice(DbPrefixes.Master.length);
+        const versionKey = versionObj.key.slice(DbPrefixes.Version.length);
+        return masterKey < versionKey ? -1 : 1;
+    }
+
+    /**
+     * Parse a listing key into its nonversioned key and version ID components
+     *
+     * @param {string} key - full listing key
+     * @return {object} obj
+     * @return {string} obj.key - nonversioned part of key
+     * @return {string} [obj.versionId] - version ID in the key
+     */
+    parseKey(fullKey: string): { key: string, versionId ?: string } {
+        const versionIdIndex = fullKey.indexOf(VID_SEP);
+        if (versionIdIndex === -1) {
+            return { key: fullKey };
+        }
+        const nonversionedKey: string = fullKey.slice(0, versionIdIndex);
+        let versionId: string = fullKey.slice(versionIdIndex + 1);
+        return { key: nonversionedKey, versionId };
+    }
+
+    /**
+     * Include a key in the listing output, in the Versions or CommonPrefix result
+     *
+     * @param {string} key - key (without version ID)
+     * @param {string} versionId - version ID
+     * @param {string} value - metadata value
+     * @return {undefined}
+     */
+    addKey(key: string, versionId: string, value: string) {
+        // add the subprefix to the common prefixes if the key has the delimiter
+        const commonPrefix = this.getCommonPrefix(key);
+        if (commonPrefix) {
+            this.addCommonPrefix(commonPrefix);
+            // transition into SkippingPrefix state to skip all following keys
+            // while they start with the same prefix
+            this.setState(<DelimiterVersionsFilterState_SkippingPrefix> {
+                id: DelimiterVersionsFilterStateId.SkippingPrefix,
+                prefix: commonPrefix,
+            });
+        } else {
+            this.addVersion(key, versionId, value);
+        }
+    }
+
+    /**
+     *  Add a (key, versionId, value) tuple to the listing.
+     *  Set the NextMarker to the current key
+     *  Increment the keys counter
+     *  @param {String} key         - The key to add
+     *  @param {String} versionId   - versionId
+     *  @param {String} value       - The value of the key
+     *  @return {undefined}
+     */
+    addVersion(key: string, versionId: string, value: string) {
+        this.Versions.push({
+            key,
+            versionId,
+            value: this.trimMetadata(value),
+        });
+        this.nextKeyMarker = key;
+        this.nextVersionIdMarker = versionId;
+        ++this.keys;
+    }
+
+    getCommonPrefix(key: string): string | undefined {
+        if (!this.delimiter) {
+            return undefined;
+        }
+        const baseIndex = this.prefix ? this.prefix.length : 0;
+        const delimiterIndex = key.indexOf(this.delimiter, baseIndex);
+        if (delimiterIndex === -1) {
+            return undefined;
+        }
+        return key.substring(0, delimiterIndex + this.delimiter.length);
+    }
+
+    /**
+     * Add a Common Prefix in the list
+     * @param {String} commonPrefix   - common prefix to add
+     * @return {undefined}
+     */
+    addCommonPrefix(commonPrefix: string): void {
+        // add the new prefix to the list
+        this.CommonPrefixes.push(commonPrefix);
+        ++this.keys;
+        this.nextKeyMarker = commonPrefix;
+        this.nextVersionIdMarker = undefined;
+    }
+
+    /**
+     * Cache the current null key, to save it for outputting it later at
+     * the correct position
+     *
+     * @param {String} key        - nonversioned key of the null key
+     * @param {String} versionId  - real version ID of the null key
+     * @param {String} value      - value of the null key
+     * @return {undefined}
+     */
+    cacheNullKey(key: string, versionId: string, value: string): void {
+        this.nullKey = { key, versionId, value };
+    }
+
+    getObjectKeyV0(obj: { key: string }): string {
+        return obj.key;
+    }
+
+    getObjectKeyV1(obj: { key: string }): string {
+        return obj.key.slice(DbPrefixes.Master.length);
+    }
+
+    /**
+     *  Filter to apply on each iteration, based on:
+     *  - prefix
+     *  - delimiter
+     *  - maxKeys
+     *  The marker is being handled directly by levelDB
+     *  @param {Object} obj       - The key and value of the element
+     *  @param {String} obj.key   - The key of the element
+     *  @param {String} obj.value - The value of the element
+     *  @return {number}          - indicates if iteration should continue
+     */
+    filter(obj: { key: string, value: string }): FilterReturnValue {
+        const key = this.getObjectKey(obj);
+        const value = obj.value;
+
+        const { key: nonversionedKey, versionId: keyVersionId } = this.parseKey(key);
+        if (this.nullKey) {
+            if (this.nullKey.key !== nonversionedKey
+                || this.nullKey.versionId < <string> keyVersionId) {
+                this.handleKey(
+                    this.nullKey.key, this.nullKey.versionId, this.nullKey.value);
+                this.nullKey = null;
+            }
+        }
+        if (keyVersionId === '') {
+            // null key
+            this.cacheNullKey(nonversionedKey, Version.from(value).getVersionId(), value);
+            if (this.state.id === DelimiterVersionsFilterStateId.SkippingVersions) {
+                return FILTER_SKIP;
+            }
+            return FILTER_ACCEPT;
+        }
+        return this.handleKey(nonversionedKey, keyVersionId, value);
+    }
+
+    setState(state: FilterState): void {
+        this.state = state;
+    }
+
+    setKeyHandler(stateId: number, keyHandler: KeyHandler): void {
+        this.keyHandlers[stateId] = keyHandler;
+    }
+
+    handleKey(key: string, versionId: string | undefined, value: string): FilterReturnValue {
+        return this.keyHandlers[this.state.id](key, versionId, value);
+    }
+
+    keyHandler_NotSkippingV0(key: string, versionId: string | undefined, value: string): FilterReturnValue {
+        if (key.startsWith(DbPrefixes.Replay)) {
+            // skip internal replay prefix entirely
+            this.setState(<DelimiterVersionsFilterState_SkippingPrefix> {
+                id: DelimiterVersionsFilterStateId.SkippingPrefix,
+                prefix: DbPrefixes.Replay,
+            });
+            return FILTER_SKIP;
+        }
+        if (Version.isPHD(value)) {
+            return FILTER_ACCEPT;
+        }
+        return this.filter_onNewKey(key, versionId, value);
+    }
+
+    keyHandler_NotSkippingV1(key: string, versionId: string | undefined, value: string): FilterReturnValue {
+        // NOTE: this check on PHD is only useful for Artesca, S3C
+        // does not use PHDs in V1 format
+        if (Version.isPHD(value)) {
+            return FILTER_ACCEPT;
+        }
+        return this.filter_onNewKey(key, versionId, value);
+    }
+
+    filter_onNewKey(key: string, versionId: string | undefined, value: string): FilterReturnValue {
+        if (this._reachedMaxKeys()) {
+            return FILTER_END;
+        }
+        if (versionId === undefined) {
+            this.masterKey = key;
+            this.masterVersionId = Version.from(value).getVersionId() || 'null';
+            this.addKey(this.masterKey, this.masterVersionId, value);
+        } else {
+            if (this.masterKey === key && this.masterVersionId === versionId) {
+                // do not add a version key if it is the master version
+                return FILTER_ACCEPT;
+            }
+            this.addKey(key, versionId, value);
+        }
+        return FILTER_ACCEPT;
+    }
+
+    keyHandler_SkippingPrefix(key: string, versionId: string | undefined, value: string): FilterReturnValue {
+        const { prefix } = <DelimiterVersionsFilterState_SkippingPrefix> this.state;
+        if (key.startsWith(prefix)) {
+            return FILTER_SKIP;
+        }
+        this.setState(<DelimiterVersionsFilterState_NotSkipping> {
+            id: DelimiterVersionsFilterStateId.NotSkipping,
+        });
+        return this.handleKey(key, versionId, value);
+    }
+
+    keyHandler_SkippingVersions(key: string, versionId: string | undefined, value: string): FilterReturnValue {
+        if (key === this.keyMarker) {
+            // since the nonversioned key equals the marker, there is
+            // necessarily a versionId in this key
+            const _versionId = <string> versionId;
+            if (_versionId < this.versionIdMarker) {
+                // skip all versions until marker
+                return FILTER_SKIP;
+            }
+            if (_versionId === this.versionIdMarker) {
+                // nothing left to skip, so return ACCEPT, but don't add this version
+                return FILTER_ACCEPT;
+            }
+        }
+        this.setState(<DelimiterVersionsFilterState_NotSkipping> {
+            id: DelimiterVersionsFilterStateId.NotSkipping,
+        });
+        return this.handleKey(key, versionId, value);
+    }
+
+    skippingBase(): string | undefined {
+        switch (this.state.id) {
+        case DelimiterVersionsFilterStateId.SkippingPrefix:
+            const { prefix } = <DelimiterVersionsFilterState_SkippingPrefix> this.state;
+            return inc(prefix);
+
+        case DelimiterVersionsFilterStateId.SkippingVersions:
+            const { gt } = <DelimiterVersionsFilterState_SkippingVersions> this.state;
+            // the contract of skipping() is to return the first key
+            // that can be skipped to, so adding a null byte to skip
+            // over the existing versioned key set in 'gt'
+            return `${gt}\0`;
+
+        default:
+            return SKIP_NONE;
+        }
+    }
+
+    skippingV0() {
+        return this.skippingBase();
+    }
+
+    skippingV1() {
+        const skipTo = this.skippingBase();
+        if (skipTo === SKIP_NONE) {
+            return SKIP_NONE;
+        }
+        // skip to the same object key in both M and V range listings
+        return [
+            `${DbPrefixes.Master}${skipTo}`,
+            `${DbPrefixes.Version}${skipTo}`,
+        ];
+    }
+
+    /**
+     *  Return an object containing all mandatory fields to use once the
+     *  iteration is done, doesn't show a NextMarker field if the output
+     *  isn't truncated
+     *  @return {Object} - following amazon format
+     */
+    result() {
+        // Add the last null key if still in cache (when it is the
+        // last version of the last key)
+        //
+        // NOTE: _reachedMaxKeys sets IsTruncated to true when it
+        // returns true. Here we want this because either:
+        //
+        // - we did not reach the max keys yet so the result is not
+        // - truncated, and there is still room for the null key in
+        // - the results
+        //
+        // - OR we reached it already while having to process a new
+        //   key (so the result is truncated even without the null key)
+        //
+        // - OR we are *just* below the limit but the null key to add
+        //   does not fit, so we know the result is now truncated
+        //   because there remains the null key to be output.
+        //
+        if (this.nullKey) {
+            this.handleKey(this.nullKey.key, this.nullKey.versionId, this.nullKey.value);
+        }
+        const result: ResultObject = {
+            CommonPrefixes: this.CommonPrefixes,
+            Versions: this.Versions,
+            IsTruncated: this.IsTruncated,
+        };
+        if (this.delimiter) {
+            result.Delimiter = this.delimiter;
+        }
+        if (this.IsTruncated) {
+            result.NextKeyMarker = this.nextKeyMarker;
+            if (this.nextVersionIdMarker) {
+                result.NextVersionIdMarker = this.nextVersionIdMarker;
+            }
+        };
+        return result;
+    }
+}
+
+module.exports = { DelimiterVersions };

lib/algos/list/exportAlgos.js

@@ -0,0 +1,12 @@
+module.exports = {
+    Basic: require('./basic').List,
+    Delimiter: require('./delimiter').Delimiter,
+    DelimiterVersions: require('./delimiterVersions')
+        .DelimiterVersions,
+    DelimiterMaster: require('./delimiterMaster')
+        .DelimiterMaster,
+    MPU: require('./MPU').MultipartUploads,
+    DelimiterCurrent: require('./delimiterCurrent').DelimiterCurrent,
+    DelimiterNonCurrent: require('./delimiterNonCurrent').DelimiterNonCurrent,
+    DelimiterOrphanDeleteMarker: require('./delimiterOrphanDeleteMarker').DelimiterOrphanDeleteMarker,
+};

lib/algos/list/skip.js

@@ -0,0 +1,85 @@
+const assert = require('assert');
+
+const { FILTER_END, FILTER_SKIP, SKIP_NONE } = require('./tools');
+
+
+const MAX_STREAK_LENGTH = 100;
+
+/**
+ * Handle the filtering and the skip mechanism of a listing result.
+ */
+class Skip {
+    /**
+     * @param {Object} params           - skip parameters
+     * @param {Object} params.extension - delimiter extension used (required)
+     * @param {String} params.gte       - current range gte (greater than or
+     *                                    equal) used by the client code
+     */
+    constructor(params) {
+        assert(params.extension);
+
+        this.extension = params.extension;
+        this.gteParams = params.gte;
+
+        this.listingEndCb = null;
+        this.skipRangeCb = null;
+
+        /* Used to count consecutive FILTER_SKIP returned by the extension
+         * filter method. Once this counter reaches MAX_STREAK_LENGTH, the
+         * filter function tries to skip unwanted values by defining a new
+         * range. */
+        this.streakLength = 0;
+    }
+
+    setListingEndCb(cb) {
+        this.listingEndCb = cb;
+    }
+
+    setSkipRangeCb(cb) {
+        this.skipRangeCb = cb;
+    }
+
+    /**
+     * Filter an entry.
+     * @param {Object} entry - entry to filter.
+     * @return {undefined}
+     *
+     * This function calls the listing end or the skip range callbacks if
+     * needed.
+     */
+    filter(entry) {
+        assert(this.listingEndCb);
+        assert(this.skipRangeCb);
+
+        const filteringResult = this.extension.filter(entry);
+        const skipTo = this.extension.skipping();
+
+        if (filteringResult === FILTER_END) {
+            this.listingEndCb();
+        } else if (filteringResult === FILTER_SKIP
+                   && skipTo !== SKIP_NONE) {
+            if (++this.streakLength >= MAX_STREAK_LENGTH) {
+                let newRange;
+                if (Array.isArray(skipTo)) {
+                    newRange = [];
+                    for (let i = 0; i < skipTo.length; ++i) {
+                        newRange.push(skipTo[i]);
+                    }
+                } else {
+                    newRange = skipTo;
+                }
+                /* Avoid to loop on the same range again and again. */
+                if (newRange === this.gteParams) {
+                    this.streakLength = 1;
+                } else {
+                    this.skipRangeCb(newRange);
+                }
+            }
+        } else {
+            this.streakLength = 0;
+        }
+    }
+}
+
+
+module.exports = Skip;

lib/algos/list/tools.js

@@ -0,0 +1,70 @@
+const { DbPrefixes } = require('../../versioning/constants').VersioningConstants;
+
+// constants for extensions
+const SKIP_NONE = undefined; // to be inline with the values of NextMarker
+const FILTER_ACCEPT = 1;
+const FILTER_SKIP = 0;
+const FILTER_END = -1;
+
+/**
+ * This function check if number is valid
+ * To be valid a number need to be an Integer and be lower than the limit
+ *                  if specified
+ * If the number is not valid the limit is returned
+ * @param {Number} number - The number to check
+ * @param {Number} limit - The limit to respect
+ * @return {Number} - The parsed number || limit
+ */
+function checkLimit(number, limit) {
+    const parsed = Number.parseInt(number, 10);
+    const valid = !Number.isNaN(parsed) && (!limit || parsed <= limit);
+    return valid ? parsed : limit;
+}
+
+/**
+ * Increment the charCode of the last character of a valid string.
+ *
+ * @param {string} str - the input string
+ * @return {string} - the incremented string
+ *                    or the input if it is not valid
+ */
+function inc(str) {
+    return str ? (str.slice(0, str.length - 1) +
+            String.fromCharCode(str.charCodeAt(str.length - 1) + 1)) : str;
+}
+
+/**
+ * Transform listing parameters for v0 versioning key format to make
+ * it compatible with v1 format
+ *
+ * @param {object} v0params - listing parameters for v0 format
+ * @return {object} - listing parameters for v1 format
+ */
+function listingParamsMasterKeysV0ToV1(v0params) {
+    const v1params = Object.assign({}, v0params);
+    if (v0params.gt !== undefined) {
+        v1params.gt = `${DbPrefixes.Master}${v0params.gt}`;
+    } else if (v0params.gte !== undefined) {
+        v1params.gte = `${DbPrefixes.Master}${v0params.gte}`;
+    } else {
+        v1params.gte = DbPrefixes.Master;
+    }
+    if (v0params.lt !== undefined) {
+        v1params.lt = `${DbPrefixes.Master}${v0params.lt}`;
+    } else if (v0params.lte !== undefined) {
+        v1params.lte = `${DbPrefixes.Master}${v0params.lte}`;
+    } else {
+        v1params.lt = inc(DbPrefixes.Master); // stop after the last master key
+    }
+    return v1params;
+}
+
+module.exports = {
+    checkLimit,
+    inc,
+    listingParamsMasterKeysV0ToV1,
+    SKIP_NONE,
+    FILTER_END,
+    FILTER_SKIP,
+    FILTER_ACCEPT,
+};

lib/algos/set/ArrayUtils.js

@@ -0,0 +1,87 @@
+function indexOf(arr, value) {
+    if (!arr.length) {
+        return -1;
+    }
+    let lo = 0;
+    let hi = arr.length - 1;
+
+    while (hi - lo > 1) {
+        const i = lo + ((hi - lo) >> 1);
+        if (arr[i] > value) {
+            hi = i;
+        } else {
+            lo = i;
+        }
+    }
+    if (arr[lo] === value) {
+        return lo;
+    }
+    if (arr[hi] === value) {
+        return hi;
+    }
+    return -1;
+}
+
+function indexAtOrBelow(arr, value) {
+    let i;
+    let lo;
+    let hi;
+
+    if (!arr.length || arr[0] > value) {
+        return -1;
+    }
+    if (arr[arr.length - 1] <= value) {
+        return arr.length - 1;
+    }
+
+    lo = 0;
+    hi = arr.length - 1;
+
+    while (hi - lo > 1) {
+        i = lo + ((hi - lo) >> 1);
+        if (arr[i] > value) {
+            hi = i;
+        } else {
+            lo = i;
+        }
+    }
+
+    return lo;
+}
+
+/*
+ * perform symmetric diff in O(m + n)
+ */
+function symDiff(k1, k2, v1, v2, cb) {
+    let i = 0;
+    let j = 0;
+    const n = k1.length;
+    const m = k2.length;
+
+    while (i < n && j < m) {
+        if (k1[i] < k2[j]) {
+            cb(v1[i]);
+            i++;
+        } else if (k2[j] < k1[i]) {
+            cb(v2[j]);
+            j++;
+        } else {
+            i++;
+            j++;
+        }
+    }
+    while (i < n) {
+        cb(v1[i]);
+        i++;
+    }
+    while (j < m) {
+        cb(v2[j]);
+        j++;
+    }
+}
+
+module.exports = {
+    indexOf,
+    indexAtOrBelow,
+    symDiff,
+};

lib/algos/set/SortedSet.js

@@ -0,0 +1,51 @@
+const ArrayUtils = require('./ArrayUtils');
+
+class SortedSet {
+    constructor(obj) {
+        if (obj) {
+            this.keys = obj.keys;
+            this.values = obj.values;
+        } else {
+            this.clear();
+        }
+    }
+
+    clear() {
+        this.keys = [];
+        this.values = [];
+    }
+
+    get size() {
+        return this.keys.length;
+    }
+
+    set(key, value) {
+        const index = ArrayUtils.indexAtOrBelow(this.keys, key);
+        if (this.keys[index] === key) {
+            this.values[index] = value;
+            return;
+        }
+        this.keys.splice(index + 1, 0, key);
+        this.values.splice(index + 1, 0, value);
+    }
+
+    isSet(key) {
+        const index = ArrayUtils.indexOf(this.keys, key);
+        return index >= 0;
+    }
+
+    get(key) {
+        const index = ArrayUtils.indexOf(this.keys, key);
+        return index >= 0 ? this.values[index] : undefined;
+    }
+
+    del(key) {
+        const index = ArrayUtils.indexOf(this.keys, key);
+        if (index >= 0) {
+            this.keys.splice(index, 1);
+            this.values.splice(index, 1);
+        }
+    }
+}
+
+module.exports = SortedSet;

lib/algos/stream/MergeStream.js

@@ -0,0 +1,106 @@
+const stream = require('stream');
+
+class MergeStream extends stream.Readable {
+    constructor(stream1, stream2, compare) {
+        super({ objectMode: true });
+
+        this._compare = compare;
+        this._streams = [stream1, stream2];
+
+        // peekItems elements represent the latest item consumed from
+        // the respective input stream but not yet pushed. It can also
+        // be one of the following special values:
+        // - undefined: stream hasn't started emitting items
+        // - null: EOF reached and no more item to peek
+        this._peekItems = [undefined, undefined];
+        this._streamEof = [false, false];
+        this._streamToResume = null;
+
+        stream1.on('data', item => this._onItem(stream1, item, 0, 1));
+        stream1.once('end', () => this._onEnd(stream1, 0, 1));
+        stream1.once('error', err => this._onError(stream1, err, 0, 1));
+
+        stream2.on('data', item => this._onItem(stream2, item, 1, 0));
+        stream2.once('end', () => this._onEnd(stream2, 1, 0));
+        stream2.once('error', err => this._onError(stream2, err, 1, 0));
+    }
+
+    _read() {
+        if (this._streamToResume) {
+            this._streamToResume.resume();
+            this._streamToResume = null;
+        }
+    }
+
+    _destroy(err, callback) {
+        for (let i = 0; i < 2; ++i) {
+            if (!this._streamEof[i]) {
+                this._streams[i].destroy();
+            }
+        }
+        callback();
+    }
+
+    _onItem(myStream, myItem, myIndex, otherIndex) {
+        this._peekItems[myIndex] = myItem;
+        const otherItem = this._peekItems[otherIndex];
+        if (otherItem === undefined) {
+            // wait for the other stream to wake up
+            return myStream.pause();
+        }
+        if (otherItem === null || this._compare(myItem, otherItem) <= 0) {
+            if (!this.push(myItem)) {
+                myStream.pause();
+                this._streamToResume = myStream;
+            }
+            return undefined;
+        }
+        const otherStream = this._streams[otherIndex];
+        const otherMore = this.push(otherItem);
+        if (this._streamEof[otherIndex]) {
+            this._peekItems[otherIndex] = null;
+            return this.push(myItem);
+        }
+        myStream.pause();
+        if (otherMore) {
+            return otherStream.resume();
+        }
+        this._streamToResume = otherStream;
+        return undefined;
+    }
+
+    _onEnd(myStream, myIndex, otherIndex) {
+        this._streamEof[myIndex] = true;
+        if (this._peekItems[myIndex] === undefined) {
+            this._peekItems[myIndex] = null;
+        }
+        const myItem = this._peekItems[myIndex];
+        const otherItem = this._peekItems[otherIndex];
+        if (otherItem === undefined) {
+            // wait for the other stream to wake up
+            return undefined;
+        }
+        if (otherItem === null) {
+            return this.push(null);
+        }
+        if (myItem === null || this._compare(myItem, otherItem) <= 0) {
+            this.push(otherItem);
+            this._peekItems[myIndex] = null;
+        }
+        if (this._streamEof[otherIndex]) {
+            return this.push(null);
+        }
+        const otherStream = this._streams[otherIndex];
+        return otherStream.resume();
+    }
+
+    _onError(myStream, err, myIndex, otherIndex) {
+        myStream.destroy();
+        if (this._streams[otherIndex]) {
+            this._streams[otherIndex].destroy();
+        }
+        this.emit('error', err);
+    }
+}
+
+module.exports = MergeStream;

lib/auth/AuthInfo.ts

@@ -0,0 +1,64 @@
+import * as constants from '../constants';
+
+/**
+ * Class containing requester's information received from Vault
+ * @param {object} info from Vault including arn, canonicalID,
+ * shortid, email, accountDisplayName and IAMdisplayName (if applicable)
+ * @return {AuthInfo} an AuthInfo instance
+ */
+export default class AuthInfo {
+    arn: string;
+    canonicalID: string;
+    shortid: string;
+    email: string;
+    accountDisplayName: string;
+    IAMdisplayName: string;
+
+    constructor(objectFromVault: any) {
+        // amazon resource name for IAM user (if applicable)
+        this.arn = objectFromVault.arn;
+        // account canonicalID
+        this.canonicalID = objectFromVault.canonicalID;
+        // shortid for account (also contained in ARN)
+        this.shortid = objectFromVault.shortid;
+        // email for account or user as applicable
+        this.email = objectFromVault.email;
+        // display name for account
+        this.accountDisplayName = objectFromVault.accountDisplayName;
+        // display name for user (if applicable)
+        this.IAMdisplayName = objectFromVault.IAMdisplayName;
+    }
+    getArn() {
+        return this.arn;
+    }
+    getCanonicalID() {
+        return this.canonicalID;
+    }
+    getShortid() {
+        return this.shortid;
+    }
+    getEmail() {
+        return this.email;
+    }
+    getAccountDisplayName() {
+        return this.accountDisplayName;
+    }
+    getIAMdisplayName() {
+        return this.IAMdisplayName;
+    }
+    // Check whether requester is an IAM user versus an account
+    isRequesterAnIAMUser() {
+        return !!this.IAMdisplayName;
+    }
+    isRequesterPublicUser() {
+        return this.canonicalID === constants.publicId;
+    }
+    isRequesterAServiceAccount() {
+        return this.canonicalID.startsWith(
+            `${constants.zenkoServiceAccount}/`);
+    }
+    isRequesterThisServiceAccount(serviceName: string) {
+        const computedCanonicalID = `${constants.zenkoServiceAccount}/${serviceName}`;
+        return this.canonicalID === computedCanonicalID;
+    }
+}

lib/auth/Vault.ts

@@ -0,0 +1,404 @@
+import { Logger } from 'werelogs';
+import errors from '../errors';
+import AuthInfo from './AuthInfo';
+
+/** vaultSignatureCb parses message from Vault and instantiates
+ * @param err - error from vault
+ * @param authInfo - info from vault
+ * @param log - log for request
+ * @param callback - callback to authCheck functions
+ * @param [streamingV4Params] - present if v4 signature;
+ * items used to calculate signature on chunks if streaming auth
+ */
+function vaultSignatureCb(
+    err: Error | null,
+    authInfo: { message: { body: any } },
+    log: Logger,
+    callback: (err: Error | null, data?: any, results?: any, params?: any, infos?: any) => void,
+    streamingV4Params?: any
+) {
+    // vaultclient API guarantees that it returns:
+    // - either `err`, an Error object with `code` and `message` properties set
+    // - or `err == null` and `info` is an object with `message.code` and
+    //   `message.message` properties set.
+    if (err) {
+        log.debug('received error message from auth provider',
+            { errorMessage: err });
+        return callback(err);
+    }
+    log.debug('received info from Vault', { authInfo });
+    const info = authInfo.message.body;
+    const userInfo = new AuthInfo(info.userInfo);
+    const authorizationResults = info.authorizationResults;
+    const auditLog: { accountDisplayName: string, IAMdisplayName?: string } =
+        { accountDisplayName: userInfo.getAccountDisplayName() };
+    const iamDisplayName = userInfo.getIAMdisplayName();
+    if (iamDisplayName) {
+        auditLog.IAMdisplayName = iamDisplayName;
+    }
+    // @ts-ignore
+    log.addDefaultFields(auditLog);
+    return callback(null, userInfo, authorizationResults, streamingV4Params, {
+        accountQuota: info.accountQuota || {},
+    });
+}
+
+export type AuthV4RequestParams = {
+    version: 4;
+    log: Logger;
+    data: {
+        accessKey: string;
+        signatureFromRequest: string;
+        region: string;
+        stringToSign: string;
+        scopeDate: string;
+        authType: 'query' | 'header';
+        signatureVersion: string;
+        signatureAge?: number;
+        timestamp: number;
+        credentialScope: string;
+        securityToken: string;
+        algo: string;
+        log: Logger;
+    };
+};
+
+/**
+ * Class that provides common authentication methods against different
+ * authentication backends.
+ * @class Vault
+ */
+export default class Vault {
+    client: any;
+    implName: string;
+
+    /**
+     * @constructor
+     * @param {object} client - authentication backend or vault client
+     * @param {string} implName - implementation name for auth backend
+     */
+    constructor(client: any, implName: string) {
+        this.client = client;
+        this.implName = implName;
+    }
+    /**
+     * authenticateV2Request
+     *
+     * @param params - the authentication parameters as returned by
+     *                          auth.extractParams
+     * @param params.version - shall equal 2
+     * @param params.data.accessKey - the user's accessKey
+     * @param params.data.signatureFromRequest - the signature read
+     *                                                    from the request
+     * @param params.data.stringToSign - the stringToSign
+     * @param params.data.algo - the hashing algorithm used for the
+     *                                    signature
+     * @param params.data.authType - the type of authentication (query
+     *                                        or header)
+     * @param params.data.signatureVersion - the version of the
+     *                                                signature (AWS or AWS4)
+     * @param [params.data.signatureAge] - the age of the signature in
+     *                                              ms
+     * @param params.data.log - the logger object
+     * @param {RequestContext []} requestContexts - an array of RequestContext
+     * instances which contain information for policy authorization check
+     * @param callback - callback with either error or user info
+     */
+    authenticateV2Request(
+        params: {
+            version: 2;
+            log: Logger;
+            data: {
+                securityToken: string;
+                accessKey: string;
+                signatureFromRequest: string;
+                stringToSign: string;
+                algo: string;
+                authType: 'query' | 'header';
+                signatureVersion: string;
+                signatureAge?: number;
+                log: Logger;
+            };
+        },
+        requestContexts: any[],
+        callback: (err: Error | null, data?: any) => void
+    ) {
+        params.log.debug('authenticating V2 request');
+        let serializedRCsArr: any;
+        if (requestContexts) {
+            serializedRCsArr = requestContexts.map(rc => rc.serialize());
+        }
+        this.client.verifySignatureV2(
+            params.data.stringToSign,
+            params.data.signatureFromRequest,
+            params.data.accessKey,
+            {
+                algo: params.data.algo,
+                // @ts-ignore
+                reqUid: params.log.getSerializedUids(),
+                logger: params.log,
+                securityToken: params.data.securityToken,
+                requestContext: serializedRCsArr,
+            },
+            (err: Error | null, userInfo?: any) => vaultSignatureCb(err, userInfo,
+                params.log, callback),
+        );
+    }
+
+    /** authenticateV4Request
+     * @param params - the authentication parameters as returned by
+     *                          auth.extractParams
+     * @param params.version - shall equal 4
+     * @param params.data.log - the logger object
+     * @param params.data.accessKey - the user's accessKey
+     * @param params.data.signatureFromRequest - the signature read
+     *                                                    from the request
+     * @param params.data.region - the AWS region
+     * @param params.data.stringToSign - the stringToSign
+     * @param params.data.scopeDate - the timespan to allow the request
+     * @param params.data.authType - the type of authentication (query
+     *                                        or header)
+     * @param params.data.signatureVersion - the version of the
+     *                                                signature (AWS or AWS4)
+     * @param params.data.signatureAge - the age of the signature in ms
+     * @param params.data.timestamp - signaure timestamp
+     * @param params.credentialScope - credentialScope for signature
+     * @param {RequestContext [] | null} requestContexts -
+     * an array of RequestContext or null if authenticaiton of a chunk
+     * in streamingv4 auth
+     * instances which contain information for policy authorization check
+     * @param callback - callback with either error or user info
+    */
+    authenticateV4Request(
+        params: AuthV4RequestParams,
+        requestContexts: any[] | null,
+        callback: (err: Error | null, data?: any) => void
+    ) {
+        params.log.debug('authenticating V4 request');
+        let serializedRCs: any;
+        if (requestContexts) {
+            serializedRCs = requestContexts.map(rc => rc.serialize());
+        }
+        const streamingV4Params = {
+            accessKey: params.data.accessKey,
+            signatureFromRequest: params.data.signatureFromRequest,
+            region: params.data.region,
+            scopeDate: params.data.scopeDate,
+            timestamp: params.data.timestamp,
+            credentialScope: params.data.credentialScope };
+        this.client.verifySignatureV4(
+            params.data.stringToSign,
+            params.data.signatureFromRequest,
+            params.data.accessKey,
+            params.data.region,
+            params.data.scopeDate,
+            {
+                // @ts-ignore
+                reqUid: params.log.getSerializedUids(),
+                logger: params.log,
+                securityToken: params.data.securityToken,
+                requestContext: serializedRCs,
+            },
+            (err: Error | null, userInfo?: any) => vaultSignatureCb(err, userInfo,
+                params.log, callback, streamingV4Params),
+        );
+    }
+
+    /** getCanonicalIds -- call Vault to get canonicalIDs based on email
+     * addresses
+     * @param emailAddresses - list of emailAddresses
+     * @param log - log object
+     * @param callback - callback with either error or an array
+     * of objects with each object containing the canonicalID and emailAddress
+     * of an account as properties
+    */
+    getCanonicalIds(
+        emailAddresses: string[],
+        log: Logger,
+        callback: (
+            err: Error | null,
+            data?: { canonicalID: string; email: string }[]
+        ) => void
+    ) {
+        log.trace('getting canonicalIDs from Vault based on emailAddresses',
+            { emailAddresses });
+        this.client.getCanonicalIds(emailAddresses,
+            // @ts-ignore
+            { reqUid: log.getSerializedUids() },
+            (err: Error | null, info?: any) => {
+                if (err) {
+                    log.debug('received error message from auth provider',
+                        { errorMessage: err });
+                    return callback(err);
+                }
+                const infoFromVault = info.message.body;
+                log.trace('info received from vault', { infoFromVault });
+                const foundIds: { canonicalID: string; email: string }[] = [];
+                for (let i = 0; i < Object.keys(infoFromVault).length; i++) {
+                    const key = Object.keys(infoFromVault)[i];
+                    if (infoFromVault[key] === 'WrongFormat'
+                    || infoFromVault[key] === 'NotFound') {
+                        return callback(errors.UnresolvableGrantByEmailAddress);
+                    }
+                    foundIds.push({
+                        email: key,
+                        canonicalID: infoFromVault[key],
+                    })
+                }
+                return callback(null, foundIds);
+            });
+    }
+
+    /** getEmailAddresses -- call Vault to get email addresses based on
+     * canonicalIDs
+     * @param canonicalIDs - list of canonicalIDs
+     * @param log - log object
+     * @param callback - callback with either error or an object
+     * with canonicalID keys and email address values
+    */
+    getEmailAddresses(
+        canonicalIDs: string[],
+        log: Logger,
+        callback: (err: Error | null, data?: { [key: string]: any }) => void
+    ) {
+        log.trace('getting emailAddresses from Vault based on canonicalIDs',
+            { canonicalIDs });
+        this.client.getEmailAddresses(canonicalIDs,
+            // @ts-ignore
+            { reqUid: log.getSerializedUids() },
+            (err: Error | null, info?: any) => {
+                if (err) {
+                    log.debug('received error message from vault',
+                        { errorMessage: err });
+                    return callback(err);
+                }
+                const infoFromVault = info.message.body;
+                log.trace('info received from vault', { infoFromVault });
+                const result = {};
+                /* If the email address was not found in Vault, do not
+                send the canonicalID back to the API */
+                Object.keys(infoFromVault).forEach(key => {
+                    if (infoFromVault[key] !== 'NotFound' &&
+                    infoFromVault[key] !== 'WrongFormat') {
+                        result[key] = infoFromVault[key];
+                    }
+                });
+                return callback(null, result);
+            });
+    }
+
+    /** getAccountIds -- call Vault to get accountIds based on
+     * canonicalIDs
+     * @param canonicalIDs - list of canonicalIDs
+     * @param log - log object
+     * @param callback - callback with either error or an object
+     * with canonicalID keys and accountId values
+    */
+    getAccountIds(
+        canonicalIDs: string[],
+        log: Logger,
+        callback: (err: Error | null, data?: { [key: string]: string }) => void
+    ) {
+        log.trace('getting accountIds from Vault based on canonicalIDs',
+            { canonicalIDs });
+        this.client.getAccountIds(canonicalIDs,
+            // @ts-expect-error
+            { reqUid: log.getSerializedUids() },
+            (err: Error | null, info?: any) => {
+                if (err) {
+                    log.debug('received error message from vault',
+                        { errorMessage: err });
+                    return callback(err);
+                }
+                const infoFromVault = info.message.body;
+                log.trace('info received from vault', { infoFromVault });
+                const result = {};
+                /* If the accountId was not found in Vault, do not
+            send the canonicalID back to the API */
+                Object.keys(infoFromVault).forEach(key => {
+                    if (infoFromVault[key] !== 'NotFound' &&
+                infoFromVault[key] !== 'WrongFormat') {
+                        result[key] = infoFromVault[key];
+                    }
+                });
+                return callback(null, result);
+            });
+    }
+
+    /** checkPolicies -- call Vault to evaluate policies
+     * @param {object} requestContextParams - parameters needed to construct
+     * requestContext in Vault
+     * @param {object} requestContextParams.constantParams - params that have
+     * the same value for each requestContext to be constructed in Vault
+     * @param {object} requestContextParams.paramaterize - params that have
+     * arrays as values since a requestContext needs to be constructed with
+     * each option in Vault
+     * @param {string} userArn - arn of requesting user
+     * @param {object} log - log object
+     * @param {function} callback - callback with either error or an array
+     * of authorization results
+    */
+    checkPolicies(
+        requestContextParams: any[],
+        userArn: string,
+        log: Logger,
+        callback: (err: Error | null, data?: any[]) => void
+    ) {
+        log.trace('sending request context params to vault to evaluate' +
+        'policies');
+        this.client.checkPolicies(requestContextParams, userArn, {
+            // @ts-ignore
+            reqUid: log.getSerializedUids(),
+        }, (err: Error | null, info?: any) => {
+            if (err) {
+                log.debug('received error message from auth provider',
+                    { error: err });
+                return callback(err);
+            }
+            const result = info.message.body;
+            return callback(null, result);
+        });
+    }
+
+    checkHealth(log: Logger, callback: (err: Error | null, data?: any) => void) {
+        if (!this.client.healthcheck) {
+            const defResp = {};
+            defResp[this.implName] = { code: 200, message: 'OK' };
+            return callback(null, defResp);
+        }
+        // @ts-ignore
+        return this.client.healthcheck(log.getSerializedUids(), (err: Error | null, obj?: any) => {
+            const respBody = {};
+            if (err) {
+                log.debug(`error from ${this.implName}`, { error: err });
+                respBody[this.implName] = {
+                    error: err,
+                };
+                // error returned as null so async parallel doesn't return
+                // before all backends are checked
+                return callback(null, respBody);
+            }
+            respBody[this.implName] = {
+                code: 200,
+                message: 'OK',
+                body: obj,
+            };
+            return callback(null, respBody);
+        });
+    }
+
+    report(log: Logger, callback: (err: Error | null, data?: any) => void) {
+        // call the report function of the client
+        if (!this.client.report) {
+            return callback(null, {});
+        }
+        // @ts-ignore
+        return this.client.report(log.getSerializedUids(), (err: Error | null, obj?: any) => {
+            if (err) {
+                log.debug(`error from ${this.implName}`, { error: err });
+                return callback(err);
+            }
+            return callback(null, obj);
+        });
+    }
+}

lib/auth/auth.ts

@@ -0,0 +1,265 @@
+import * as crypto from 'crypto';
+import { Logger } from 'werelogs';
+import errors from '../errors';
+import * as queryString from 'querystring';
+import AuthInfo from './AuthInfo';
+import * as v2 from './v2/authV2';
+import * as v4 from './v4/authV4';
+import * as constants from '../constants';
+import constructStringToSignV2 from './v2/constructStringToSign';
+import constructStringToSignV4 from './v4/constructStringToSign';
+import { convertUTCtoISO8601 } from './v4/timeUtils';
+import * as vaultUtilities from './backends/in_memory/vaultUtilities';
+import * as inMemoryBackend from './backends/in_memory/Backend';
+import baseBackend from './backends/base';
+import chainBackend from './backends/ChainBackend';
+import validateAuthConfig from './backends/in_memory/validateAuthConfig';
+import AuthLoader from './backends/in_memory/AuthLoader';
+import Vault from './Vault';
+
+let vault: Vault | null = null;
+const auth = {};
+const checkFunctions = {
+    v2: {
+        headers: v2.header.check,
+        query: v2.query.check,
+    },
+    v4: {
+        headers: v4.header.check,
+        query: v4.query.check,
+    },
+};
+
+// If no auth information is provided in request, then user is part of
+// 'All Users Group' so use this group as the canonicalID for the publicUser
+const publicUserInfo = new AuthInfo({ canonicalID: constants.publicId });
+
+function setAuthHandler(handler: Vault) {
+    vault = handler;
+    return auth;
+}
+
+/**
+ * This function will check validity of request parameters to authenticate
+ *
+ * @param request - Http request object
+ * @param log - Logger object
+ * @param awsService - Aws service related
+ * @param data - Parameters from queryString parsing or body of
+ *      POST request
+ *
+ * @return ret
+ * @return ret.err - arsenal.errors object if any error was found
+ * @return ret.params - auth parameters to use later on for signature
+ *                               computation and check
+ * @return ret.params.version - the auth scheme version
+ *                                       (undefined, 2, 4)
+ * @return ret.params.data - the auth scheme's specific data
+ */
+function extractParams(
+    request: any,
+    log: Logger,
+    awsService: string,
+    data: { [key: string]: string }
+) {
+    log.trace('entered', { method: 'Arsenal.auth.server.extractParams' });
+    const authHeader = request.headers.authorization;
+    let version: 'v2' |'v4' | null = null;
+    let method: 'query' | 'headers' | null = null;
+
+    // Identify auth version and method to dispatch to the right check function
+    if (authHeader) {
+        method = 'headers';
+        // TODO: Check for security token header to handle temporary security
+        // credentials
+        if (authHeader.startsWith('AWS ')) {
+            version = 'v2';
+        } else if (authHeader.startsWith('AWS4')) {
+            version = 'v4';
+        } else {
+            log.trace('invalid authorization security header',
+                { header: authHeader });
+            return { err: errors.AccessDenied };
+        }
+    } else if (data.Signature) {
+        method = 'query';
+        version = 'v2';
+    } else if (data['X-Amz-Algorithm']) {
+        method = 'query';
+        version = 'v4';
+    }
+
+    // Here, either both values are set, or none is set
+    if (version !== null && method !== null) {
+        if (!checkFunctions[version] || !checkFunctions[version][method]) {
+            log.trace('invalid auth version or method',
+                { version, authMethod: method });
+            return { err: errors.NotImplemented };
+        }
+        log.trace('identified auth method', { version, authMethod: method });
+        return checkFunctions[version][method](request, log, data, awsService);
+    }
+
+    // no auth info identified
+    log.debug('assuming public user');
+    return { err: null, params: publicUserInfo };
+}
+
+/**
+ * This function will check validity of request parameters to authenticate
+ *
+ * @param request - Http request object
+ * @param log - Logger object
+ * @param cb - the callback
+ * @param awsService - Aws service related
+ * @param {RequestContext[] | null} requestContexts - array of RequestContext
+ * or null if no requestContexts to be sent to Vault (for instance,
+ * in multi-object delete request)
+ */
+function doAuth(
+    request: any,
+    log: Logger,
+    cb: (err: Error | null, data?: any) => void,
+    awsService: string,
+    requestContexts: any[] | null
+) {
+    const res = extractParams(request, log, awsService, request.query);
+    if (res.err) {
+        return cb(res.err);
+    } else if (res.params instanceof AuthInfo) {
+        return cb(null, res.params);
+    }
+    if (requestContexts) {
+        requestContexts.forEach((requestContext) => {
+            const { params } = res
+            if ('data' in params) {
+                const { data } = params
+                requestContext.setAuthType(data.authType);
+                requestContext.setSignatureVersion(data.signatureVersion);
+                requestContext.setSecurityToken(data.securityToken);
+                if ('signatureAge' in data) {
+                    requestContext.setSignatureAge(data.signatureAge);
+                }
+            }
+        });
+    }
+
+    // Corner cases managed, we're left with normal auth
+    // TODO What's happening here?
+    // @ts-ignore
+    res.params.log = log;
+    if (res.params.version === 2) {
+        // @ts-ignore
+        return vault!.authenticateV2Request(res.params, requestContexts, cb);
+    }
+    if (res.params.version === 4) {
+        // @ts-ignore
+        return vault!.authenticateV4Request(res.params, requestContexts, cb);
+    }
+
+    log.error('authentication method not found', {
+        method: 'Arsenal.auth.doAuth',
+    });
+    return cb(errors.InternalError);
+}
+
+/**
+ * This function will generate a version 4 content-md5 header
+ * It looks at the request path to determine what kind of header encoding is required
+ *
+ * @param path - the request path
+ * @param payload - the request payload to hash
+ */
+function generateContentMD5Header(
+    path: string,
+    payload: string,
+) {
+    const encoding = path && path.startsWith('/_/backbeat/') ? 'hex' : 'base64';
+    return crypto.createHash('md5').update(payload, 'binary').digest(encoding);
+}
+/**
+ * This function will generate a version 4 header
+ *
+ * @param request - Http request object
+ * @param data - Parameters from queryString parsing or body of
+ *                        POST request
+ * @param accessKey - the accessKey
+ * @param secretKeyValue - the secretKey
+ * @param awsService - Aws service related
+ * @param [proxyPath] - path that gets proxied by reverse proxy
+ * @param [sessionToken] - security token if the access/secret keys
+ *                                are temporary credentials from STS
+ * @param [payload] - body of the request if any
+ */
+function generateV4Headers(
+    request: any,
+    data: { [key: string]: string },
+    accessKey: string,
+    secretKeyValue: string,
+    awsService: string,
+    proxyPath?: string,
+    sessionToken?: string,
+    payload?: string,
+) {
+    Object.assign(request, { headers: {} });
+    const amzDate = convertUTCtoISO8601(Date.now());
+    // get date without time
+    const scopeDate = amzDate.slice(0, amzDate.indexOf('T'));
+    const region = 'us-east-1';
+    const service = awsService || 'iam';
+    const credentialScope =
+        `${scopeDate}/${region}/${service}/aws4_request`;
+    const timestamp = amzDate;
+    const algorithm = 'AWS4-HMAC-SHA256';
+
+    payload = payload || '';
+    if (request.method === 'POST') {
+        payload = queryString.stringify(data, undefined, undefined, {
+            encodeURIComponent,
+        });
+    }
+    const payloadChecksum = crypto.createHash('sha256')
+        .update(payload, 'binary').digest('hex');
+    request.setHeader('host', request._headers.host);
+    request.setHeader('x-amz-date', amzDate);
+    request.setHeader('x-amz-content-sha256', payloadChecksum);
+    request.setHeader('content-md5', generateContentMD5Header(request.path, payload));
+
+    if (sessionToken) {
+        request.setHeader('x-amz-security-token', sessionToken);
+    }
+
+    Object.assign(request.headers, request._headers);
+    const signedHeaders = Object.keys(request._headers)
+        .filter(headerName =>
+            headerName.startsWith('x-amz-')
+            || headerName.startsWith('x-scal-')
+            || headerName === 'content-md5'
+            || headerName === 'host',
+        ).sort().join(';');
+    const params = { request, signedHeaders, payloadChecksum,
+        credentialScope, timestamp, query: data,
+        awsService: service, proxyPath };
+    const stringToSign = constructStringToSignV4(params);
+    const signingKey = vaultUtilities.calculateSigningKey(secretKeyValue,
+        region,
+        scopeDate,
+        service);
+    const signature = crypto.createHmac('sha256', signingKey)
+        .update(stringToSign as string, 'binary').digest('hex');
+    const authorizationHeader = `${algorithm} Credential=${accessKey}` +
+        `/${credentialScope}, SignedHeaders=${signedHeaders}, ` +
+        `Signature=${signature}`;
+    request.setHeader('authorization', authorizationHeader);
+    Object.assign(request, { headers: {} });
+}
+
+export const server = { extractParams, doAuth }
+export const client = { generateV4Headers, constructStringToSignV2 }
+export const inMemory = { backend: inMemoryBackend, validateAuthConfig, AuthLoader }
+export const backends = { baseBackend, chainBackend }
+export {
+    setAuthHandler as setHandler,
+    AuthInfo,
+    Vault
+}

lib/auth/backends/ChainBackend.ts

@@ -0,0 +1,233 @@
+import assert from 'assert';
+import async from 'async';
+import errors from '../../errors';
+import BaseBackend from './base';
+
+/**
+ * Class that provides an authentication backend that will verify signatures
+ * and retrieve emails and canonical ids associated with an account using a
+ * given list of authentication backends and vault clients.
+ *
+ * @class ChainBackend
+ */
+export default class ChainBackend extends BaseBackend {
+    _clients: any[];
+
+    /**
+     * @constructor
+     * @param {string} service - service id
+     * @param {object[]} clients - list of authentication backends or vault clients
+     */
+    constructor(service: string, clients: any[]) {
+        super(service);
+
+        assert(Array.isArray(clients) && clients.length > 0, 'invalid client list');
+        assert(clients.every(client =>
+            typeof client.verifySignatureV4 === 'function' &&
+            typeof client.verifySignatureV2 === 'function' &&
+            typeof client.getCanonicalIds === 'function' &&
+            typeof client.getEmailAddresses === 'function' &&
+            typeof client.checkPolicies === 'function' &&
+            typeof client.healthcheck === 'function',
+        ), 'invalid client: missing required auth backend methods');
+        this._clients = clients;
+    }
+
+
+    /*
+     * try task against each client for one to be successful
+     */
+    _tryEachClient(task: any, cb: any) {
+        // @ts-ignore
+        async.tryEach(this._clients.map(client => done => task(client, done)), cb);
+    }
+
+    /*
+     * apply task to all clients
+     */
+    _forEachClient(task: any, cb: any) {
+        async.map(this._clients, task, cb);
+    }
+
+    verifySignatureV2(
+        stringToSign: string,
+        signatureFromRequest: string,
+        accessKey: string,
+        options: any,
+        callback: any,
+      ) {
+        this._tryEachClient((client, done) => client.verifySignatureV2(
+            stringToSign,
+            signatureFromRequest,
+            accessKey,
+            options,
+            done,
+        ), callback);
+    }
+
+    verifySignatureV4(
+      stringToSign: string,
+      signatureFromRequest: string,
+      accessKey: string,
+      region: string,
+      scopeDate: string,
+      options: any,
+      callback: any,
+    ) {
+        this._tryEachClient((client, done) => client.verifySignatureV4(
+            stringToSign,
+            signatureFromRequest,
+            accessKey,
+            region,
+            scopeDate,
+            options,
+            done,
+        ), callback);
+    }
+
+    static _mergeObjects(objectResponses: any) {
+        return objectResponses.reduce(
+            (retObj, resObj) => Object.assign(retObj, resObj.message.body),
+            {});
+    }
+
+    getCanonicalIds(emailAddresses: string[], options: any, callback: any) {
+        this._forEachClient(
+            (client, done) => client.getCanonicalIds(emailAddresses, options, done),
+            (err, res) => {
+                if (err) {
+                    return callback(err);
+                }
+                // TODO: atm naive merge, better handling of conflicting email results
+                return callback(null, {
+                    message: {
+                        body: ChainBackend._mergeObjects(res),
+                    },
+                });
+            });
+    }
+
+    getEmailAddresses(canonicalIDs: string[], options: any, callback: any) {
+        this._forEachClient(
+            (client, done) => client.getEmailAddresses(canonicalIDs, options, done),
+            (err, res) => {
+                if (err) {
+                    return callback(err);
+                }
+                return callback(null, {
+                    message: {
+                        body: ChainBackend._mergeObjects(res),
+                    },
+                });
+            });
+    }
+
+    /*
+     * merge policy responses into a single message
+     */
+    static _mergePolicies(policyResponses: any) {
+        const policyMap: any = {};
+
+        policyResponses.forEach(resp => {
+            if (!resp.message || !Array.isArray(resp.message.body)) {
+                return;
+            }
+
+            const check = (policy) => {
+                const key = (policy.arn || '') + (policy.versionId || '') + (policy.action || '');
+                if (!policyMap[key] || !policyMap[key].isAllowed) {
+                    policyMap[key] = policy;
+                }
+                // else is duplicate policy
+            };
+
+            resp.message.body.forEach(policy => {
+                if (Array.isArray(policy)) {
+                    policy.forEach(authResult => check(authResult));
+                } else {
+                    check(policy);
+                }
+            });
+        });
+
+        return Object.keys(policyMap).map(key => {
+            const policyRes: any = { isAllowed: policyMap[key].isAllowed };
+            if (policyMap[key].arn !== '') {
+                policyRes.arn = policyMap[key].arn;
+            }
+            if (policyMap[key].versionId) {
+                policyRes.versionId = policyMap[key].versionId;
+            }
+            if (policyMap[key].isImplicit !== undefined) {
+                policyRes.isImplicit = policyMap[key].isImplicit;
+            }
+            if (policyMap[key].action) {
+                policyRes.action = policyMap[key].action;
+            }
+            return policyRes;
+        });
+    }
+
+    /*
+        response format:
+            {  message: {
+                body: [{}],
+                code: number,
+                message: string,
+            } }
+     */
+    checkPolicies(requestContextParams: any, userArn: string, options: any, callback: any) {
+        this._forEachClient((client, done) => client.checkPolicies(
+            requestContextParams,
+            userArn,
+            options,
+            done,
+        ), (err, res) => {
+            if (err) {
+                return callback(err);
+            }
+            return callback(null, {
+                message: {
+                    body: ChainBackend._mergePolicies(res),
+                },
+            });
+        });
+    }
+
+    healthcheck(reqUid: string, callback: any) {
+        this._forEachClient((client, done) =>
+            client.healthcheck(reqUid, (err, res) => done(null, {
+                error: !!err ? err : null,
+                status: res,
+            }),
+            ), (err, res) => {
+            if (err) {
+                return callback(err);
+            }
+
+            const isError = res.some(results => !!results.error);
+            if (isError) {
+                return callback(errors.InternalError, res);
+            }
+            return callback(null, res);
+        });
+    }
+
+    report(reqUid: string, callback: any) {
+        this._forEachClient((client, done) =>
+            client.report(reqUid, done),
+            (err, res) => {
+                if (err) {
+                    return callback(err);
+                }
+                const mergedRes = res.reduce((acc, val) => {
+                    Object.keys(val).forEach(k => {
+                        acc[k] = val[k];
+                    });
+                    return acc;
+                }, {});
+
+                return callback(null, mergedRes);
+            });
+    }
+}

lib/auth/backends/base.ts

@@ -0,0 +1,96 @@
+import errors from '../../errors';
+
+/**
+ * Base backend class
+ *
+ * @class BaseBackend
+ */
+export default class BaseBackend {
+    service: string;
+
+    /**
+     * @constructor
+     * @param {string} service - service identifer for construction arn
+     */
+    constructor(service: string) {
+        this.service = service;
+    }
+
+    /** verifySignatureV2
+    * @param stringToSign - string to sign built per AWS rules
+    * @param signatureFromRequest - signature sent with request
+    * @param accessKey - account accessKey
+    * @param options - contains algorithm (SHA1 or SHA256)
+    * @param callback - callback with either error or user info
+    * @return calls callback
+    */
+    verifySignatureV2(
+        stringToSign: string,
+        signatureFromRequest: string,
+        accessKey: string,
+        options: any,
+        callback: any
+    ) {
+        return callback(errors.AuthMethodNotImplemented);
+    }
+
+
+    /** verifySignatureV4
+     * @param stringToSign - string to sign built per AWS rules
+     * @param signatureFromRequest - signature sent with request
+     * @param accessKey - account accessKey
+     * @param region - region specified in request credential
+     * @param scopeDate - date specified in request credential
+     * @param options - options to send to Vault
+     * (just contains reqUid for logging in Vault)
+     * @param callback - callback with either error or user info
+     * @return calls callback
+     */
+    verifySignatureV4(
+        stringToSign: string,
+        signatureFromRequest: string,
+        accessKey: string,
+        region: string,
+        scopeDate: string,
+        options: any,
+        callback: any
+    ) {
+        return callback(errors.AuthMethodNotImplemented);
+    }
+
+    /**
+     * Gets canonical ID's for a list of accounts
+     * based on email associated with account
+     * @param emails - list of email addresses
+     * @param options - to send log id to vault
+     * @param callback - callback to calling function
+     * @returns callback with either error or
+     * object with email addresses as keys and canonical IDs
+     * as values
+     */
+    getCanonicalIds(emails: string[], options: any, callback: any) {
+        return callback(errors.AuthMethodNotImplemented);
+    }
+
+    /**
+     * Gets email addresses (referred to as diplay names for getACL's)
+     * for a list of accounts based on canonical IDs associated with account
+     * @param canonicalIDs - list of canonicalIDs
+     * @param options - to send log id to vault
+     * @param callback - callback to calling function
+     * @returns callback with either error or
+     * an object from Vault containing account canonicalID
+     * as each object key and an email address as the value (or "NotFound")
+     */
+    getEmailAddresses(canonicalIDs: string[], options: any, callback: any) {
+        return callback(errors.AuthMethodNotImplemented);
+    }
+
+    checkPolicies(requestContextParams: any, userArn: string, options: any, callback: any) {
+        return callback(null, { message: { body: [] } });
+    }
+
+    healthcheck(reqUid: string, callback: any) {
+        return callback(null, { code: 200, message: 'OK' });
+    }
+}

lib/auth/backends/in_memory/AuthLoader.ts

@@ -0,0 +1,204 @@
+import * as fs from 'fs';
+import glob from 'simple-glob';
+import joi from 'joi';
+import werelogs from 'werelogs';
+import * as types from './types';
+import { Account, Accounts } from './types';
+import ARN from '../../../models/ARN';
+
+/** Load authentication information from files or pre-loaded account objects */
+export default class AuthLoader {
+    #log: werelogs.Logger;
+    #authData: Accounts;
+    #isValid: 'waiting-for-validation' | 'valid' | 'invalid';
+
+    constructor(logApi: { Logger: typeof werelogs.Logger } = werelogs) {
+        this.#log = new logApi.Logger('S3');
+        this.#authData = { accounts: [] };
+        this.#isValid = 'waiting-for-validation';
+    }
+
+    /** Add one or more accounts to the authentication info */
+    addAccounts(authData: Accounts, filePath?: string) {
+        const isValid = this.#isAuthDataValid(authData, filePath);
+        if (isValid) {
+            this.#authData.accounts = [
+                ...this.#authData.accounts,
+                ...authData.accounts,
+            ];
+            // defer validity checking when getting data to avoid
+            // logging multiple times the errors (we need to validate
+            // all accounts at once to detect duplicate values)
+            if (this.#isValid === 'valid') {
+                this.#isValid = 'waiting-for-validation';
+            }
+        } else {
+            this.#isValid = 'invalid';
+        }
+    }
+
+    /**
+     * Add account information from a file. Use { legacy: false } as an option
+     *  to use the new, Promise-based version.
+     *
+     * @param filePath - file path containing JSON
+     *   authentication info (see {@link addAccounts()} for format)
+     */
+    addFile(filePath: string, options: { legacy: false }): Promise<void>;
+    /** @deprecated Please use Promise-version instead. */
+    addFile(filePath: string, options?: { legacy: true }): void;
+    addFile(filePath: string, options = { legacy: true }) {
+        // On deprecation, remove the legacy part and keep the promises.
+        const readFunc: any = options.legacy ? fs.readFileSync : fs.promises.readFile;
+        const readResult = readFunc(filePath, 'utf8') as Promise<string> | string;
+        const prom = Promise.resolve(readResult).then((data) => {
+            const authData = JSON.parse(data);
+            this.addAccounts(authData, filePath);
+        });
+        return options.legacy ? undefined : prom;
+    }
+
+    /**
+     * Add account information from a filesystem path
+     *
+     * @param globPattern - filesystem glob pattern,
+     *   can be a single string or an array of glob patterns. Globs
+     *   can be simple file paths or can contain glob matching
+     *   characters, like '/a/b/*.json'. The matching files are
+     *   individually loaded as JSON and accounts are added. See
+     *   {@link addAccounts()} for JSON format.
+     */
+    addFilesByGlob(globPattern: string | string[]) {
+        // FIXME switch glob to async version
+        const files = glob(globPattern);
+        files.forEach((filePath) => this.addFile(filePath));
+    }
+
+    /**
+     * Perform validation on authentication info previously
+     * loaded. Note that it has to be done on the entire set after an
+     * update to catch duplicate account IDs or access keys.
+     */
+    validate() {
+        if (this.#isValid === 'waiting-for-validation') {
+            const isValid = this.#isAuthDataValid(this.#authData);
+            this.#isValid = isValid ? 'valid' : 'invalid';
+        }
+        return this.#isValid === 'valid';
+    }
+
+    /**
+     * Get authentication info as a plain JS object containing all accounts
+     * under the "accounts" attribute, with validation.
+     */
+    get data() {
+        return this.validate() ? this.#authData : null;
+    }
+
+    /** backward-compat: ignore arn if starts with 'aws:' and log a warning */
+    #isNotLegacyAWSARN(account: Account, filePath?: string) {
+        if (account.arn.startsWith('aws:')) {
+            const { name: accountName, arn: accountArn } = account;
+            this.#log.error(
+                'account must have a valid AWS ARN, legacy examples ' +
+                    "starting with 'aws:' are not supported anymore. " +
+                    'Please convert to a proper account entry (see ' +
+                    'examples at https://github.com/scality/S3/blob/' +
+                    'master/conf/authdata.json). Also note that support ' +
+                    'for account users has been dropped.',
+                { accountName, accountArn, filePath }
+            );
+            return false;
+        }
+        return true;
+    }
+
+    #isValidUsers(account: Account, filePath?: string) {
+        if (account.users) {
+            const { name: accountName, arn: accountArn } = account;
+            this.#log.error(
+                'support for account users has been dropped, consider ' +
+                    'turning users into account entries (see examples at ' +
+                    'https://github.com/scality/S3/blob/master/conf/' +
+                    'authdata.json)',
+                { accountName, accountArn, filePath }
+            );
+            return false;
+        }
+        return true;
+    }
+
+    #isValidARN(account: Account, filePath?: string) {
+        const arnObj = ARN.createFromString(account.arn);
+        const { name: accountName, arn: accountArn } = account;
+        if (arnObj instanceof ARN) {
+            if (!arnObj.isIAMAccount()) {
+                this.#log.error('authentication config validation error', {
+                    reason: 'not an IAM account ARN',
+                    accountName,
+                    accountArn,
+                    filePath,
+                });
+                return false;
+            }
+        } else {
+            this.#log.error('authentication config validation error', {
+                reason: arnObj.error.description,
+                accountName,
+                accountArn,
+                filePath,
+            });
+            return false;
+        }
+        return true;
+    }
+
+    #isAuthDataValid(authData: any, filePath?: string) {
+        const options = { abortEarly: true };
+        const response = types.validators.accounts.validate(authData, options);
+        if (response.error) {
+            this.#dumpJoiErrors(response.error.details, filePath);
+            return false;
+        }
+        const validAccounts = response.value.accounts.filter(
+            (account: Account) =>
+                this.#isNotLegacyAWSARN(account, filePath) &&
+                this.#isValidUsers(account, filePath) &&
+                this.#isValidARN(account, filePath)
+        );
+        const areSomeInvalidAccounts =
+            validAccounts.length !== response.value.accounts.length;
+        if (areSomeInvalidAccounts) {
+            return false;
+        }
+        const keys = validAccounts.flatMap((account) => account.keys);
+        const uniqueKeysValidator = types.validators.keys.unique('access');
+        const areKeysUnique = uniqueKeysValidator.validate(keys);
+        if (areKeysUnique.error) {
+            this.#dumpJoiErrors(areKeysUnique.error.details, filePath);
+            return false;
+        }
+        return true;
+    }
+
+    #dumpJoiErrors(errors: joi.ValidationErrorItem[], filePath?: string) {
+        errors.forEach((err) => {
+            const baseLogInfo = { item: err.path, filePath };
+            const logInfo = () => {
+                if (err.type === 'array.unique') {
+                    const reason = `duplicate value '${err.context?.path}'`;
+                    const dupValue = err.context?.value[err.context.path];
+                    return { ...baseLogInfo, reason, dupValue };
+                } else {
+                    const reason = err.message;
+                    const context = err.context;
+                    return { ...baseLogInfo, reason, context };
+                }
+            };
+            this.#log.error(
+                'authentication config validation error',
+                logInfo()
+            );
+        });
+    }
+}

lib/auth/backends/in_memory/Backend.ts

@@ -0,0 +1,194 @@
+import crypto from 'crypto';
+import { Logger } from 'werelogs';
+import errors from '../../../errors';
+import { calculateSigningKey, hashSignature } from './vaultUtilities';
+import Indexer from './Indexer';
+import BaseBackend from '../base';
+import { Accounts } from './types';
+
+function _formatResponse(userInfoToSend: any) {
+    return {
+        message: {
+            body: { userInfo: userInfoToSend },
+        },
+    };
+}
+
+/**
+ * Class that provides a memory backend for verifying signatures and getting
+ * emails and canonical ids associated with an account.
+ *
+ * @class InMemoryBackend
+ */
+class InMemoryBackend extends BaseBackend {
+    indexer: Indexer;
+    formatResponse: any;
+
+    /**
+     * @constructor
+     * @param service - service identifer for construction arn
+     * @param indexer - indexer instance for retrieving account info
+     * @param formatter - function which accepts user info to send
+     * back and returns it in an object
+     */
+    constructor(service: string, indexer: Indexer, formatter: typeof _formatResponse) {
+        super(service);
+        this.indexer = indexer;
+        this.formatResponse = formatter;
+    }
+
+    verifySignatureV2(
+        stringToSign: string,
+        signatureFromRequest: string,
+        accessKey: string,
+        options: any,
+        callback: any,
+    ) {
+        const entity = this.indexer.getEntityByKey(accessKey);
+        if (!entity) {
+            return callback(errors.InvalidAccessKeyId);
+        }
+        const secretKey = this.indexer.getSecretKey(entity, accessKey);
+        const reconstructedSig =
+            hashSignature(stringToSign, secretKey, options.algo);
+        if (signatureFromRequest !== reconstructedSig) {
+            return callback(errors.SignatureDoesNotMatch);
+        }
+        const userInfoToSend = {
+            accountDisplayName: this.indexer.getAcctDisplayName(entity),
+            canonicalID: entity.canonicalID,
+            arn: entity.arn,
+            // @ts-ignore
+            IAMdisplayName: entity.IAMdisplayName,
+        };
+        const vaultReturnObject = this.formatResponse(userInfoToSend);
+        return callback(null, vaultReturnObject);
+    }
+
+    verifySignatureV4(
+        stringToSign: string,
+        signatureFromRequest: string,
+        accessKey: string,
+        region: string,
+        scopeDate: string,
+        options: any,
+        callback: any,
+    ) {
+        const entity = this.indexer.getEntityByKey(accessKey);
+        if (!entity) {
+            return callback(errors.InvalidAccessKeyId);
+        }
+        const secretKey = this.indexer.getSecretKey(entity, accessKey);
+        const signingKey = calculateSigningKey(secretKey, region, scopeDate);
+        const reconstructedSig = crypto.createHmac('sha256', signingKey)
+            .update(stringToSign, 'binary').digest('hex');
+        if (signatureFromRequest !== reconstructedSig) {
+            return callback(errors.SignatureDoesNotMatch);
+        }
+        const userInfoToSend = {
+            accountDisplayName: this.indexer.getAcctDisplayName(entity),
+            canonicalID: entity.canonicalID,
+            arn: entity.arn,
+            // @ts-ignore
+            IAMdisplayName: entity.IAMdisplayName,
+        };
+        const vaultReturnObject = this.formatResponse(userInfoToSend);
+        return callback(null, vaultReturnObject);
+    }
+
+    getCanonicalIds(emails: string[], log: Logger, cb: any) {
+        const results = {};
+        emails.forEach(email => {
+            const lowercasedEmail = email.toLowerCase();
+            const entity = this.indexer.getEntityByEmail(lowercasedEmail);
+            if (!entity) {
+                results[email] = 'NotFound';
+            } else {
+                results[email] =
+                    entity.canonicalID;
+            }
+        });
+        const vaultReturnObject = {
+            message: {
+                body: results,
+            },
+        };
+        return cb(null, vaultReturnObject);
+    }
+
+    getEmailAddresses(canonicalIDs: string[], options: any, cb: any) {
+        const results = {};
+        canonicalIDs.forEach(canonicalId => {
+            const foundEntity = this.indexer.getEntityByCanId(canonicalId);
+            if (!foundEntity || !foundEntity.email) {
+                results[canonicalId] = 'NotFound';
+            } else {
+                results[canonicalId] = foundEntity.email;
+            }
+        });
+        const vaultReturnObject = {
+            message: {
+                body: results,
+            },
+        };
+        return cb(null, vaultReturnObject);
+    }
+
+    /**
+     * Gets accountIds for a list of accounts based on
+     * the canonical IDs associated with the account
+     * @param canonicalIDs - list of canonicalIDs
+     * @param options - to send log id to vault
+     * @param cb - callback to calling function
+     * @returns callback with either error or
+     * an object from Vault containing account canonicalID
+     * as each object key and an accountId as the value (or "NotFound")
+     */
+    getAccountIds(canonicalIDs: string[], options: any, cb: any) {
+        const results = {};
+        canonicalIDs.forEach(canonicalID => {
+            const foundEntity = this.indexer.getEntityByCanId(canonicalID);
+            if (!foundEntity || !foundEntity.shortid) {
+                results[canonicalID] = 'Not Found';
+            } else {
+                results[canonicalID] = foundEntity.shortid;
+            }
+        });
+        const vaultReturnObject = {
+            message: {
+                body: results,
+            },
+        };
+        return cb(null, vaultReturnObject);
+    }
+
+    report(log: Logger, callback: any) {
+        return callback(null, {});
+    }
+}
+
+
+class S3AuthBackend extends InMemoryBackend {
+    /**
+     * @constructor
+     * @param authdata - the authentication config file's data
+     * @param authdata.accounts - array of account objects
+     * @param authdata.accounts[].name - account name
+     * @param authdata.accounts[].email - account email
+     * @param authdata.accounts[].arn - IAM resource name
+     * @param authdata.accounts[].canonicalID - account canonical ID
+     * @param authdata.accounts[].shortid - short account ID
+     * @param authdata.accounts[].keys - array of key objects
+     * @param authdata.accounts[].keys[].access - access key
+     * @param authdata.accounts[].keys[].secret - secret key
+     */
+    constructor(authdata?: Accounts) {
+        super('s3', new Indexer(authdata), _formatResponse);
+    }
+
+    refreshAuthData(authData?: Accounts) {
+        this.indexer = new Indexer(authData);
+    }
+}
+
+export { S3AuthBackend as s3 }

lib/auth/backends/in_memory/Indexer.ts

@@ -0,0 +1,93 @@
+import { Accounts, Account, Entity } from './types';
+
+/**
+ * Class that provides an internal indexing over the simple data provided by
+ * the authentication configuration file for the memory backend. This allows
+ * accessing the different authentication entities through various types of
+ * keys.
+ */
+export default class Indexer {
+    accountsBy: {
+        canId: { [id: string]: Entity | undefined },
+        accessKey: { [id: string]: Entity | undefined },
+        email: { [id: string]: Entity | undefined },
+    }
+
+    constructor(authdata?: Accounts) {
+        this.accountsBy = {
+            canId: {},
+            accessKey: {},
+            email: {},
+        };
+
+        /*
+         * This may happen if the application is configured to use another
+         * authentication backend than in-memory.
+         * As such, we're managing the error here to avoid screwing up there.
+         */
+        if (!authdata) {
+            return;
+        }
+
+        this.#build(authdata);
+    }
+
+    #indexAccount(account: Account) {
+        const accountData: Entity = {
+            arn: account.arn,
+            canonicalID: account.canonicalID,
+            shortid: account.shortid,
+            accountDisplayName: account.name,
+            email: account.email.toLowerCase(),
+            keys: [],
+        };
+        this.accountsBy.canId[accountData.canonicalID] = accountData;
+        this.accountsBy.email[accountData.email] = accountData;
+        if (account.keys !== undefined) {
+            account.keys.forEach(key => {
+                accountData.keys.push(key);
+                this.accountsBy.accessKey[key.access] = accountData;
+            });
+        }
+    }
+
+    #build(authdata: Accounts) {
+        authdata.accounts.forEach(account => {
+            this.#indexAccount(account);
+        });
+    }
+
+    /** This method returns the account associated to a canonical ID. */
+    getEntityByCanId(canId: string): Entity | undefined {
+        return this.accountsBy.canId[canId];
+    }
+
+    /**
+     * This method returns the entity (either an account or a user) associated
+     * to a canonical ID.
+     * @param {string} key - The accessKey of the entity
+     */
+    getEntityByKey(key: string): Entity | undefined {
+        return this.accountsBy.accessKey[key];
+    }
+
+    /**
+     * This method returns the entity (either an account or a user) associated
+     * to an email address.
+     */
+    getEntityByEmail(email: string): Entity | undefined {
+        const lowerCasedEmail = email.toLowerCase();
+        return this.accountsBy.email[lowerCasedEmail];
+    }
+
+    /** This method returns the secret key associated with the entity. */
+    getSecretKey(entity: Entity, accessKey: string) {
+        const keys = entity.keys.filter(kv => kv.access === accessKey);
+        return keys[0].secret;
+    }
+
+    /** This method returns the account display name associated with the entity. */
+    getAcctDisplayName(entity: Entity) {
+        return entity.accountDisplayName;
+    }
+}

lib/auth/backends/in_memory/types.ts

@@ -0,0 +1,51 @@
+import joi from 'joi';
+
+export type Callback<Data = any> = (err?: Error | null | undefined, data?: Data) => void;
+
+export type Credentials = { access: string; secret: string };
+export type Base = {
+    arn: string;
+    canonicalID: string;
+    shortid: string;
+    email: string;
+    keys: Credentials[];
+};
+export type Account = Base & { name: string; users: any[] };
+export type Accounts = { accounts: Account[] };
+export type Entity = Base & { accountDisplayName: string };
+
+const keys = ((): joi.ArraySchema => {
+    const str = joi.string().required();
+    const items = { access: str, secret: str };
+    return joi.array().items(items).required();
+})();
+
+const account = (() => {
+    return joi.object<Account>({
+        name: joi.string().required(),
+        email: joi.string().email().required(),
+        arn: joi.string().required(),
+        canonicalID: joi.string().required(),
+        shortid: joi
+            .string()
+            .regex(/^[0-9]{12}$/)
+            .required(),
+        keys: keys,
+        // backward-compat
+        users: joi.array(),
+    });
+})();
+
+const accounts = (() => {
+    return joi.object<Accounts>({
+        accounts: joi
+            .array()
+            .items(account)
+            .required()
+            .unique('arn')
+            .unique('email')
+            .unique('canonicalID'),
+    });
+})();
+
+export const validators = { keys, account, accounts };

lib/auth/backends/in_memory/validateAuthConfig.ts

@@ -0,0 +1,16 @@
+import { Logger } from 'werelogs';
+import AuthLoader from './AuthLoader';
+import { Accounts } from './types';
+
+/**
+ * @deprecated please use {@link AuthLoader} class instead
+ * @return true on erroneous data false on success
+ */
+export default function validateAuthConfig(
+    authdata: Accounts,
+    logApi?: { Logger: typeof Logger }
+) {
+    const authLoader = new AuthLoader(logApi);
+    authLoader.addAccounts(authdata);
+    return !authLoader.validate();
+}

lib/auth/backends/in_memory/vaultUtilities.ts

@@ -0,0 +1,40 @@
+import * as crypto from 'crypto';
+
+/** hashSignature for v2 Auth
+ * @param {string} stringToSign - built string to sign per AWS rules
+ * @param {string} secretKey - user's secretKey
+ * @param {string} algorithm - either SHA256 or SHA1
+ * @return {string} reconstructed signature
+ */
+export function hashSignature(
+    stringToSign: string,
+    secretKey: string,
+    algorithm: 'SHA256' | 'SHA1'
+): string {
+    const hmacObject = crypto.createHmac(algorithm, secretKey);
+    return hmacObject.update(stringToSign, 'binary').digest('base64');
+}
+
+const sha256Digest = (key: string | Buffer, data: string) => {
+    return crypto.createHmac('sha256', key).update(data, 'binary').digest();
+};
+
+/** calculateSigningKey for v4 Auth
+ * @param {string} secretKey - requester's secretKey
+ * @param {string} region - region included in request
+ * @param {string} scopeDate - scopeDate included in request
+ * @param {string} [service] - To specify another service than s3
+ * @return {string} signingKey - signingKey to calculate signature
+ */
+export function calculateSigningKey(
+    secretKey: string,
+    region: string,
+    scopeDate: string,
+    service?: string
+): Buffer {
+    const dateKey = sha256Digest(`AWS4${secretKey}`, scopeDate);
+    const dateRegionKey = sha256Digest(dateKey, region);
+    const dateRegionServiceKey = sha256Digest(dateRegionKey, service || 's3');
+    const signingKey = sha256Digest(dateRegionServiceKey, 'aws4_request');
+    return signingKey;
+}

lib/auth/v2/algoCheck.ts

@@ -0,0 +1,16 @@
+export default function algoCheck(signatureLength: number) {
+    let algo: 'sha256' | 'sha1';
+    // If the signature sent is 44 characters,
+    // this means that sha256 was used:
+    // 44 characters in base64
+    const SHA256LEN = 44;
+    const SHA1LEN = 28;
+    if (signatureLength === SHA256LEN) {
+        algo = 'sha256';
+    }
+    if (signatureLength === SHA1LEN) {
+        algo = 'sha1';
+    }
+    // @ts-ignore
+    return algo;
+}

lib/auth/v2/authV2.ts

@@ -0,0 +1,2 @@
+export * as header from './headerAuthCheck';
+export * as query from './queryAuthCheck';

lib/auth/v2/checkRequestExpiry.ts

@@ -0,0 +1,34 @@
+import { Logger } from 'werelogs';
+import errors from '../../errors';
+
+const epochTime = new Date('1970-01-01').getTime();
+
+export default function checkRequestExpiry(timestamp: number, log: Logger) {
+    // If timestamp is before epochTime, the request is invalid and return
+    // errors.AccessDenied
+    if (timestamp < epochTime) {
+        log.debug('request time is invalid', { timestamp });
+        return errors.AccessDenied;
+    }
+    // If timestamp is not within 15 minutes of current time, or if
+    // timestamp is more than 15 minutes in the future, the request
+    // has expired and return errors.RequestTimeTooSkewed
+    const currentTime = Date.now();
+    log.trace('request timestamp', { requestTimestamp: timestamp });
+    log.trace('current timestamp', { currentTimestamp: currentTime });
+
+    const fifteenMinutes = (15 * 60 * 1000);
+    if (currentTime - timestamp > fifteenMinutes) {
+        log.trace('request timestamp is not within 15 minutes of current time');
+        log.debug('request time too skewed', { timestamp });
+        return errors.RequestTimeTooSkewed;
+    }
+
+    if (currentTime + fifteenMinutes < timestamp) {
+        log.trace('request timestamp is more than 15 minutes into future');
+        log.debug('request time too skewed', { timestamp });
+        return errors.RequestTimeTooSkewed;
+    }
+
+    return undefined;
+}

lib/auth/v2/constructStringToSign.ts

@@ -0,0 +1,47 @@
+import { Logger } from 'werelogs';
+import utf8 from 'utf8';
+import getCanonicalizedAmzHeaders from './getCanonicalizedAmzHeaders';
+import getCanonicalizedResource from './getCanonicalizedResource';
+
+export default function constructStringToSign(
+    request: any,
+    data: { [key: string]: string },
+    log: Logger,
+    clientType?: any
+) {
+    /*
+    Build signature per AWS requirements:
+    StringToSign = HTTP-Verb + '\n' +
+    Content-MD5 + '\n' +
+    Content-Type + '\n' +
+    Date (or Expiration for query Auth) + '\n' +
+    CanonicalizedAmzHeaders +
+    CanonicalizedResource;
+    */
+    log.trace('constructing string to sign');
+
+    let stringToSign = `${request.method}\n`;
+    const headers = request.headers;
+    const query = data;
+
+    const contentMD5 = headers['content-md5'] ?
+        headers['content-md5'] : query['Content-MD5'];
+    stringToSign += (contentMD5 ? `${contentMD5}\n` : '\n');
+
+    const contentType = headers['content-type'] ?
+        headers['content-type'] : query['Content-Type'];
+    stringToSign += (contentType ? `${contentType}\n` : '\n');
+
+    /*
+    AWS docs are conflicting on whether to include x-amz-date header here
+    if present in request.
+    s3cmd includes x-amz-date in amzHeaders rather
+    than here in stringToSign so we have replicated that.
+    */
+    const date = query.Expires ? query.Expires : headers.date;
+    const combinedQueryHeaders = Object.assign({}, headers, query);
+    stringToSign += (date ? `${date}\n` : '\n')
+        + getCanonicalizedAmzHeaders(combinedQueryHeaders, clientType)
+        + getCanonicalizedResource(request, clientType);
+    return utf8.encode(stringToSign);
+}

lib/auth/v2/getCanonicalizedAmzHeaders.ts

@@ -0,0 +1,43 @@
+export default function getCanonicalizedAmzHeaders(headers: Headers, clientType: string) {
+    /*
+    Iterate through headers and pull any headers that are x-amz headers.
+    Need to include 'x-amz-date' here even though AWS docs
+    ambiguous on this.
+    */
+    const filterFn = clientType === 'GCP' ?
+        (val: string) => val.substr(0, 7) === 'x-goog-' :
+        (val: string) => val.substr(0, 6) === 'x-amz-';
+    const amzHeaders = Object.keys(headers)
+        .filter(filterFn)
+        .map(val => [val.trim(), headers[val].trim()]);
+    /*
+    AWS docs state that duplicate headers should be combined
+    in the same header with values concatenated with
+    a comma separation.
+    Node combines duplicate headers and concatenates the values
+    with a comma AND SPACE separation.
+    Could replace all occurrences of ', ' with ',' but this
+    would remove spaces that might be desired
+    (for instance, in date header).
+    Opted to proceed without this parsing since it does not appear
+    that the AWS clients use duplicate headers.
+    */
+
+    // If there are no amz headers, just return an empty string
+    if (amzHeaders.length === 0) {
+        return '';
+    }
+
+
+    // Sort the amz headers by key (first item in tuple)
+    amzHeaders.sort((a, b) => {
+        if (a[0] > b[0]) {
+            return 1;
+        }
+        return -1;
+    });
+    // Build headerString
+    return amzHeaders.reduce((headerStr, current) =>
+        `${headerStr}${current[0]}:${current[1]}\n`,
+    '');
+}

lib/auth/v2/getCanonicalizedResource.ts

@@ -0,0 +1,117 @@
+import * as url from 'url';
+
+const gcpSubresources = [
+    'acl',
+    'billing',
+    'compose',
+    'cors',
+    'encryption',
+    'lifecycle',
+    'location',
+    'logging',
+    'storageClass',
+    'tagging',
+    'upload_id',
+    'versioning',
+    'versions',
+    'websiteConfig',
+];
+
+const awsSubresources = [
+    'acl',
+    'cors',
+    'delete',
+    'lifecycle',
+    'location',
+    'logging',
+    'notification',
+    'partNumber',
+    'policy',
+    'requestPayment',
+    'tagging',
+    'torrent',
+    'uploadId',
+    'uploads',
+    'versionId',
+    'versioning',
+    'replication',
+    'versions',
+    'website',
+];
+
+export default function getCanonicalizedResource(request: any, clientType: string) {
+    /*
+    This variable is used to determine whether to insert
+    a '?' or '&'.  Once a query parameter is added to the resourceString,
+    it changes to '&' before any new query parameter is added.
+    */
+    let queryChar = '?';
+    // If bucket specified in hostname, add to resourceString
+    let resourceString = request.gotBucketNameFromHost ?
+        `/${request.bucketName}` : '';
+    // Add the path to the resourceString
+    resourceString += url.parse(request.url).pathname;
+
+    /*
+    If request includes a specified subresource,
+    add to the resourceString: (a) a '?', (b) the subresource,
+    and (c) its value (if any).
+    Separate multiple subresources with '&'.
+    Subresources must be in alphabetical order.
+    */
+
+    // Specified subresources:
+    const subresources =
+        clientType === 'GCP' ? gcpSubresources : awsSubresources;
+
+    /*
+    If the request includes parameters in the query string,
+    that override the headers, include
+    them in the resourceString
+    along with their values.
+    AWS is ambiguous about format.  Used alphabetical order.
+    */
+    const overridingParams = [
+        'response-cache-control',
+        'response-content-disposition',
+        'response-content-encoding',
+        'response-content-language',
+        'response-content-type',
+        'response-expires',
+    ];
+
+    // Check which specified subresources are present in query string,
+    // build array with them
+    const query = request.query;
+    const presentSubresources = Object.keys(query).filter(val =>
+        subresources.indexOf(val) !== -1);
+    // Sort the array and add the subresources and their value (if any)
+    // to the resourceString
+    presentSubresources.sort();
+    resourceString = presentSubresources.reduce((prev, current) => {
+        const ch = (query[current] !== '' ? '=' : '');
+        const ret = `${prev}${queryChar}${current}${ch}${query[current]}`;
+        queryChar = '&';
+        return ret;
+    }, resourceString);
+    // Add the overriding parameters to our resourceString
+    resourceString = overridingParams.reduce((prev, current) => {
+        if (query[current]) {
+            const ret = `${prev}${queryChar}${current}=${query[current]}`;
+            queryChar = '&';
+            return ret;
+        }
+        return prev;
+    }, resourceString);
+
+    /*
+    Per AWS, the delete query string parameter must be included when
+    you create the CanonicalizedResource for a multi-object Delete request.
+    Unclear what this means for a single item delete request.
+    */
+    if (request.query.delete) {
+        // Addresses adding '?' instead of '&' if no other params added.
+        resourceString += `${queryChar}delete=${query.delete}`;
+    }
+    return resourceString;
+}

lib/auth/v2/headerAuthCheck.ts

@@ -0,0 +1,82 @@
+import { Logger } from 'werelogs';
+import errors from '../../errors';
+import * as constants from '../../constants';
+import constructStringToSign from './constructStringToSign';
+import checkRequestExpiry from './checkRequestExpiry';
+import algoCheck from './algoCheck';
+
+export function check(request: any, log: Logger, data: { [key: string]: string }) {
+    log.trace('running header auth check');
+    const headers = request.headers;
+
+    const token = headers['x-amz-security-token'];
+    if (token && !constants.iamSecurityToken.pattern.test(token)) {
+        log.debug('invalid security token', { token });
+        return { err: errors.InvalidToken };
+    }
+
+    // Check to make sure timestamp is within 15 minutes of current time
+    let timestamp = headers['x-amz-date'] ?
+        headers['x-amz-date'] : headers.date;
+    timestamp = Date.parse(timestamp);
+    if (!timestamp) {
+        log.debug('missing or invalid date header',
+            { method: 'auth/v2/headerAuthCheck.check' });
+        return { err: errors.AccessDenied.
+            customizeDescription('Authentication requires a valid Date or ' +
+          'x-amz-date header') };
+    }
+
+    const err = checkRequestExpiry(timestamp, log);
+    if (err) {
+        return { err };
+    }
+
+    // Authorization Header should be
+    // in the format of 'AWS AccessKey:Signature'
+    const authInfo = headers.authorization;
+
+    if (!authInfo) {
+        log.debug('missing authorization security header');
+        return { err: errors.MissingSecurityHeader };
+    }
+    const semicolonIndex = authInfo.indexOf(':');
+    if (semicolonIndex < 0) {
+        log.debug('invalid authorization header', { authInfo });
+        return { err: errors.InvalidArgument };
+    }
+    const accessKey = semicolonIndex > 4 ?
+        authInfo.substring(4, semicolonIndex).trim() : undefined;
+    if (typeof accessKey !== 'string' || accessKey.length === 0) {
+        log.trace('invalid authorization header', { authInfo });
+        return { err: errors.MissingSecurityHeader };
+    }
+    // @ts-ignore
+    log.addDefaultFields({ accessKey });
+
+    const signatureFromRequest = authInfo.substring(semicolonIndex + 1).trim();
+    log.trace('signature from request', { signatureFromRequest });
+    const stringToSign = constructStringToSign(request, data, log);
+    log.trace('constructed string to sign', { stringToSign });
+    const algo = algoCheck(signatureFromRequest.length);
+    log.trace('algo for calculating signature', { algo });
+    if (algo === undefined) {
+        return { err: errors.InvalidArgument };
+    }
+    return {
+        err: null,
+        params: {
+            version: 2,
+            data: {
+                accessKey,
+                signatureFromRequest,
+                stringToSign,
+                algo,
+                authType: 'REST-HEADER',
+                signatureVersion: 'AWS',
+                signatureAge: Date.now() - timestamp,
+                securityToken: token,
+            },
+        },
+    };
+}

lib/auth/v2/queryAuthCheck.ts

@@ -0,0 +1,84 @@
+import { Logger } from 'werelogs';
+import errors from '../../errors';
+import * as constants from '../../constants';
+import algoCheck from './algoCheck';
+import constructStringToSign from './constructStringToSign';
+
+export function check(request: any, log: Logger, data: { [key: string]: string }) {
+    log.trace('running query auth check');
+    if (request.method === 'POST') {
+        log.debug('query string auth not supported for post requests');
+        return { err: errors.NotImplemented };
+    }
+
+    const token = data.SecurityToken;
+    if (token && !constants.iamSecurityToken.pattern.test(token)) {
+        log.debug('invalid security token', { token });
+        return { err: errors.InvalidToken };
+    }
+
+    /*
+    Check whether request has expired or if
+    expires parameter is more than 604800000 milliseconds
+    (7 days) in the future.
+    Expires time is provided in seconds so need to
+    multiply by 1000 to obtain
+    milliseconds to compare to Date.now()
+    */
+    const expirationTime = parseInt(data.Expires, 10) * 1000;
+    if (Number.isNaN(expirationTime)) {
+        log.debug('invalid expires parameter',
+            { expires: data.Expires });
+        return { err: errors.MissingSecurityHeader };
+    }
+
+    const currentTime = Date.now();
+
+    const preSignedURLExpiry = process.env.PRE_SIGN_URL_EXPIRY
+        && !Number.isNaN(process.env.PRE_SIGN_URL_EXPIRY)
+        ? Number.parseInt(process.env.PRE_SIGN_URL_EXPIRY, 10)
+        : constants.defaultPreSignedURLExpiry * 1000;
+
+    if (expirationTime > currentTime + preSignedURLExpiry) {
+        log.debug('expires parameter too far in future',
+            { expires: request.query.Expires });
+        return { err: errors.AccessDenied };
+    }
+    if (currentTime > expirationTime) {
+        log.debug('current time exceeds expires time',
+            { expires: request.query.Expires });
+        return { err: errors.RequestTimeTooSkewed };
+    }
+    const accessKey = data.AWSAccessKeyId;
+    // @ts-ignore
+    log.addDefaultFields({ accessKey });
+
+    const signatureFromRequest = decodeURIComponent(data.Signature);
+    log.trace('signature from request', { signatureFromRequest });
+    if (!accessKey || !signatureFromRequest) {
+        log.debug('invalid access key/signature parameters');
+        return { err: errors.MissingSecurityHeader };
+    }
+    const stringToSign = constructStringToSign(request, data, log);
+    log.trace('constructed string to sign', { stringToSign });
+    const algo = algoCheck(signatureFromRequest.length);
+    log.trace('algo for calculating signature', { algo });
+    if (algo === undefined) {
+        return { err: errors.InvalidArgument };
+    }
+    return {
+        err: null,
+        params: {
+            version: 2,
+            data: {
+                accessKey,
+                signatureFromRequest,
+                stringToSign,
+                algo,
+                authType: 'REST-QUERY-STRING',
+                signatureVersion: 'AWS',
+                securityToken: token,
+            },
+        },
+    };
+}

lib/auth/v4/authV4.ts

@@ -0,0 +1,2 @@
+export * as header from './headerAuthCheck';
+export * as query from './queryAuthCheck';

lib/auth/v4/awsURIencode.ts

@@ -0,0 +1,81 @@
+/*
+AWS's URI encoding rules:
+URI encode every byte. Uri-Encode() must enforce the following rules:
+
+URI encode every byte except the unreserved characters:
+'A'-'Z', 'a'-'z', '0'-'9', '-', '.', '_', and '~'.
+The space character is a reserved character and must be
+encoded as "%20" (and not as "+").
+Each Uri-encoded byte is formed by a '%' and the two-digit
+hexadecimal value of the byte.
+Letters in the hexadecimal value must be uppercase, for example "%1A".
+Encode the forward slash character, '/',
+everywhere except in the object key name.
+For example, if the object key name is photos/Jan/sample.jpg,
+the forward slash in the key name is not encoded.
+See http://docs.aws.amazon.com/AmazonS3/latest/API/sig-v4-header-based-auth.html
+*/
+
+// converts utf8 character to hex and pads "%" before every two hex digits
+function _toHexUTF8(char: string) {
+    const hexRep = Buffer.from(char, 'utf8').toString('hex').toUpperCase();
+    let res = '';
+    hexRep.split('').forEach((v, n) => {
+        // pad % before every 2 hex digits
+        if (n % 2 === 0) {
+            res += '%';
+        }
+        res += v;
+    });
+    return res;
+}
+
+export default function awsURIencode(
+    input: string,
+    encodeSlash?: boolean,
+    noEncodeStar?: boolean
+) {
+    /**
+     * Duplicate query params are not suppported by AWS S3 APIs. These params
+     * are parsed as Arrays by Node.js HTTP parser which breaks this method
+     */
+     if (typeof input !== 'string') {
+        return '';
+    }
+    let encoded = "";
+    const slash = encodeSlash === undefined || encodeSlash ? '%2F' : '/';
+    const star = noEncodeStar !== undefined && noEncodeStar ? '*' : '%2A';
+    for (let i = 0; i < input.length; i++) {
+        let ch = input.charAt(i);
+        if ((ch >= 'A' && ch <= 'Z') ||
+            (ch >= 'a' && ch <= 'z') ||
+            (ch >= '0' && ch <= '9') ||
+            ch === '_' || ch === '-' ||
+            ch === '~' || ch === '.') {
+            encoded = encoded.concat(ch);
+        } else if (ch === ' ') {
+            encoded = encoded.concat('%20');
+        } else if (ch === '/') {
+            encoded = encoded.concat(slash);
+        } else if (ch === '*') {
+            encoded = encoded.concat(star);
+        } else {
+            if (ch >= '\uD800' && ch <= '\uDBFF') {
+                // If this character is a high surrogate peek the next character
+                // and join it with this one if the next character is a low
+                // surrogate.
+                // Otherwise the encoded URI will contain the two surrogates as
+                // two distinct UTF-8 sequences which is not valid UTF-8.
+                if (i + 1 < input.length) {
+                    const ch2 = input.charAt(i + 1);
+                    if (ch2 >= '\uDC00' && ch2 <= '\uDFFF') {
+                        i++;
+                        ch += ch2;
+                    }
+                }
+            }
+            encoded = encoded.concat(_toHexUTF8(ch));
+        }
+    }
+    return encoded;
+}

lib/auth/v4/constructStringToSign.ts

@@ -0,0 +1,60 @@
+import * as crypto from 'crypto';
+import { Logger } from 'werelogs';
+import createCanonicalRequest from './createCanonicalRequest';
+
+/**
+ * constructStringToSign - creates V4 stringToSign
+ * @param {object} params - params object
+ * @returns {string} - stringToSign
+ */
+export default function constructStringToSign(params: {
+    request: any;
+    signedHeaders: any;
+    payloadChecksum: any;
+    credentialScope: string;
+    timestamp: string;
+    query: { [key: string]: string };
+    log?: Logger;
+    proxyPath?: string;
+    awsService: string;
+}): string | Error {
+    const {
+        request,
+        signedHeaders,
+        payloadChecksum,
+        credentialScope,
+        timestamp,
+        query,
+        log,
+        proxyPath,
+    } = params;
+    const path = proxyPath || request.path;
+
+    const canonicalReqResult = createCanonicalRequest({
+        pHttpVerb: request.method,
+        pResource: path,
+        pQuery: query,
+        pHeaders: request.headers,
+        pSignedHeaders: signedHeaders,
+        payloadChecksum,
+        service: params.awsService,
+    });
+
+    // TODO Why that line?
+    // @ts-ignore
+    if (canonicalReqResult instanceof Error) {
+        if (log) {
+            log.error('error creating canonicalRequest');
+        }
+        return canonicalReqResult;
+    }
+    if (log) {
+        log.debug('constructed canonicalRequest', { canonicalReqResult });
+    }
+    const sha256 = crypto.createHash('sha256');
+    const canonicalHex = sha256.update(canonicalReqResult, 'binary')
+        .digest('hex');
+    const stringToSign = `AWS4-HMAC-SHA256\n${timestamp}\n` +
+    `${credentialScope}\n${canonicalHex}`;
+    return stringToSign;
+}

lib/auth/v4/createCanonicalRequest.ts

@@ -0,0 +1,95 @@
+import * as crypto from 'crypto';
+import * as queryString from 'querystring';
+import awsURIencode from './awsURIencode';
+
+/**
+ * createCanonicalRequest - creates V4 canonical request
+ * @param params - contains pHttpVerb (request type),
+ * pResource (parsed from URL), pQuery (request query),
+ * pHeaders (request headers), pSignedHeaders (signed headers from request),
+ * payloadChecksum (from request)
+ * @returns - canonicalRequest
+ */
+export default function createCanonicalRequest(
+    params: {
+        pHttpVerb: string;
+        pResource: string;
+        pQuery: { [key: string]: string };
+        pHeaders: any;
+        pSignedHeaders: any;
+        service: string;
+        payloadChecksum: string;
+    }
+) {
+    const pHttpVerb = params.pHttpVerb;
+    const pResource = params.pResource;
+    const pQuery = params.pQuery;
+    const pHeaders = params.pHeaders;
+    const pSignedHeaders = params.pSignedHeaders;
+    const service = params.service;
+    let payloadChecksum = params.payloadChecksum;
+    if (!payloadChecksum) {
+        if (pHttpVerb === 'GET') {
+            payloadChecksum = 'e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b' +
+                '934ca495991b7852b855';
+        } else if (pHttpVerb === 'POST') {
+            let notEncodeStar = false;
+            // The java sdk does not encode the '*' parameter to compute the
+            // signature, if the user-agent is recognized, we need to keep
+            // the plain '*' as well.
+            if (/aws-sdk-java\/[0-9.]+/.test(pHeaders['user-agent'])) {
+                notEncodeStar = true;
+            }
+            let payload = queryString.stringify(pQuery, undefined, undefined, {
+                encodeURIComponent: input => awsURIencode(input, true,
+                    notEncodeStar),
+            });
+            payload = payload.replace(/%20/g, '+');
+            payloadChecksum = crypto.createHash('sha256')
+                .update(payload, 'binary').digest('hex').toLowerCase();
+        }
+    }
+
+    const canonicalURI = !!pResource ? awsURIencode(pResource, false) : '/';
+
+    // canonical query string
+    let canonicalQueryStr = '';
+    if (pQuery && !((service === 'iam' || service === 'ring' ||
+        service === 'sts') &&
+        pHttpVerb === 'POST')) {
+        const sortedQueryParams = Object.keys(pQuery).sort().map(key => {
+            const encodedKey = awsURIencode(key);
+            const value = pQuery[key] ? awsURIencode(pQuery[key]) : '';
+            return `${encodedKey}=${value}`;
+        });
+        canonicalQueryStr = sortedQueryParams.join('&');
+    }
+
+    // signed headers
+    const signedHeadersList = pSignedHeaders.split(';');
+    signedHeadersList.sort((a: any, b: any) => a.localeCompare(b));
+    const signedHeaders = signedHeadersList.join(';');
+
+    // canonical headers
+    const canonicalHeadersList = signedHeadersList.map((signedHeader: any) => {
+        if (pHeaders[signedHeader] !== undefined) {
+            const trimmedHeader = pHeaders[signedHeader]
+                .trim().replace(/\s+/g, ' ');
+            return `${signedHeader}:${trimmedHeader}\n`;
+        }
+        // nginx will strip the actual expect header so add value of
+        // header back here if it was included as a signed header
+        if (signedHeader === 'expect') {
+            return `${signedHeader}:100-continue\n`;
+        }
+        // handle case where signed 'header' is actually query param
+        return `${signedHeader}:${pQuery[signedHeader]}\n`;
+    });
+
+    const canonicalHeaders = canonicalHeadersList.join('');
+
+    const canonicalRequest = `${pHttpVerb}\n${canonicalURI}\n` +
+        `${canonicalQueryStr}\n${canonicalHeaders}\n` +
+        `${signedHeaders}\n${payloadChecksum}`;
+    return canonicalRequest;
+}

lib/auth/v4/headerAuthCheck.ts

@@ -0,0 +1,185 @@
+import { Logger } from 'werelogs';
+import errors from '../../../lib/errors';
+import * as constants from '../../constants';
+import constructStringToSign from './constructStringToSign';
+import {
+    checkTimeSkew,
+    convertUTCtoISO8601,
+    convertAmzTimeToMs,
+} from './timeUtils';
+import {
+    extractAuthItems,
+    validateCredentials,
+    areSignedHeadersComplete,
+} from './validateInputs';
+
+/**
+ * V4 header auth check
+ * @param request - HTTP request object
+ * @param log - logging object
+ * @param data - Parameters from queryString parsing or body of
+ *      POST request
+ * @param awsService - Aws service ('iam' or 's3')
+ */
+export function check(
+    request: any,
+    log: Logger,
+    data: { [key: string]: string },
+    awsService: string
+) {
+    log.trace('running header auth check');
+
+    const token = request.headers['x-amz-security-token'];
+    if (token && !constants.iamSecurityToken.pattern.test(token)) {
+        log.debug('invalid security token', { token });
+        return { err: errors.InvalidToken };
+    }
+
+    // authorization header
+    const authHeader = request.headers.authorization;
+    if (!authHeader) {
+        log.debug('missing authorization header');
+        return { err: errors.MissingSecurityHeader };
+    }
+
+    const authHeaderItems = extractAuthItems(authHeader, log);
+    if (Object.keys(authHeaderItems).length < 3) {
+        log.debug('invalid authorization header', { authHeader });
+        return { err: errors.InvalidArgument };
+    }
+
+    const payloadChecksum = request.headers['x-amz-content-sha256'];
+    if (!payloadChecksum && awsService !== 'iam') {
+        log.debug('missing payload checksum');
+        return { err: errors.MissingSecurityHeader };
+    }
+    if (payloadChecksum === 'STREAMING-AWS4-HMAC-SHA256-PAYLOAD') {
+        log.trace('requesting streaming v4 auth');
+        if (request.method !== 'PUT') {
+            log.debug('streaming v4 auth for put only',
+                { method: 'auth/v4/headerAuthCheck.check' });
+            return { err: errors.InvalidArgument };
+        }
+        if (!request.headers['x-amz-decoded-content-length']) {
+            return { err: errors.MissingSecurityHeader };
+        }
+    }
+
+    log.trace('authorization header from request', { authHeader });
+
+    const signatureFromRequest = authHeaderItems.signatureFromRequest!;
+    const credentialsArr = authHeaderItems.credentialsArr!;
+    const signedHeaders = authHeaderItems.signedHeaders!;
+
+    if (!areSignedHeadersComplete(signedHeaders, request.headers)) {
+        log.debug('signedHeaders are incomplete', { signedHeaders });
+        return { err: errors.AccessDenied };
+    }
+
+    let timestamp: string | undefined;
+    // check request timestamp
+    const xAmzDate = request.headers['x-amz-date'];
+    if (xAmzDate) {
+        const xAmzDateArr = xAmzDate.split('T');
+        // check that x-amz- date has the correct format and after epochTime
+        if (xAmzDateArr.length === 2 && xAmzDateArr[0].length === 8
+          && xAmzDateArr[1].length === 7
+          && Number.parseInt(xAmzDateArr[0], 10) > 19700101) {
+            // format of x-amz- date is ISO 8601: YYYYMMDDTHHMMSSZ
+            timestamp = request.headers['x-amz-date'];
+        }
+    } else if (request.headers.date) {
+        timestamp = convertUTCtoISO8601(request.headers.date);
+    }
+    if (!timestamp) {
+        log.debug('missing or invalid date header',
+            { method: 'auth/v4/headerAuthCheck.check' });
+        return { err: errors.AccessDenied.
+            customizeDescription('Authentication requires a valid Date or ' +
+          'x-amz-date header') };
+    }
+
+    const validationResult = validateCredentials(credentialsArr, timestamp,
+        log);
+    if (validationResult instanceof Error) {
+        log.debug('credentials in improper format', { credentialsArr,
+            timestamp, validationResult });
+        return { err: validationResult };
+    }
+    // credentialsArr is [accessKey, date, region, aws-service, aws4_request]
+    const scopeDate = credentialsArr[1];
+    const region = credentialsArr[2];
+    const service = credentialsArr[3];
+    const accessKey = credentialsArr.shift();
+    const credentialScope = credentialsArr.join('/');
+
+    // In AWS Signature Version 4, the signing key is valid for up to seven days
+    // (see Introduction to Signing Requests.
+    // Therefore, a signature is also valid for up to seven days or
+    // less if specified by a bucket policy.
+    // Since policies are not yet implemented, we will have a 15
+    // minute default like in v2 Auth.
+    // See http://docs.aws.amazon.com/AmazonS3/latest/API/
+    // bucket-policy-s3-sigv4-conditions.html
+    // TODO: When implementing bucket policies,
+    // note that expiration can be shortened so
+    // expiry is as set out in the policy.
+
+    // 15 minutes in seconds
+    const expiry = (15 * 60);
+    const isTimeSkewed = checkTimeSkew(timestamp, expiry, log);
+    if (isTimeSkewed) {
+        return { err: errors.RequestTimeTooSkewed };
+    }
+
+    let proxyPath: string | undefined;
+    if (request.headers.proxy_path) {
+        try {
+            proxyPath = decodeURIComponent(request.headers.proxy_path);
+        } catch (err) {
+            log.debug('invalid proxy_path header', { proxyPath, err });
+            return { err: errors.InvalidArgument.customizeDescription(
+                'invalid proxy_path header') };
+        }
+    }
+
+    const stringToSign = constructStringToSign({
+        log,
+        request,
+        query: data,
+        signedHeaders,
+        credentialScope,
+        timestamp,
+        payloadChecksum,
+        awsService: service,
+        proxyPath,
+    });
+    log.trace('constructed stringToSign', { stringToSign });
+    if (stringToSign instanceof Error) {
+        return { err: stringToSign };
+    }
+
+
+    return {
+        err: null,
+        params: {
+            version: 4,
+            data: {
+                accessKey,
+                signatureFromRequest,
+                region,
+                service,
+                scopeDate,
+                stringToSign,
+                authType: 'REST-HEADER',
+                signatureVersion: 'AWS4-HMAC-SHA256',
+                signatureAge: Date.now() - convertAmzTimeToMs(timestamp),
+                // credentialScope and timestamp needed for streaming V4
+                // chunk evaluation
+                credentialScope,
+                timestamp,
+                securityToken: token,
+            },
+        },
+    };
+}

lib/auth/v4/queryAuthCheck.ts

@@ -0,0 +1,118 @@
+import { Logger } from 'werelogs';
+import * as constants from '../../constants';
+import errors from '../../errors';
+import constructStringToSign from './constructStringToSign';
+import { checkTimeSkew, convertAmzTimeToMs } from './timeUtils';
+import { validateCredentials, extractQueryParams } from './validateInputs';
+import { areSignedHeadersComplete } from './validateInputs';
+
+/**
+ * V4 query auth check
+ * @param request - HTTP request object
+ * @param log - logging object
+ * @param data - Contain authentification params (GET or POST data)
+ */
+export function check(request: any, log: Logger, data: { [key: string]: string }) {
+    const authParams = extractQueryParams(data, log);
+
+    if (Object.keys(authParams).length !== 5) {
+        return { err: errors.InvalidArgument };
+    }
+
+    // Query params are not specified in AWS documentation as case-insensitive,
+    // so we use case-sensitive
+    const token = data['X-Amz-Security-Token'];
+    if (token && !constants.iamSecurityToken.pattern.test(token)) {
+        log.debug('invalid security token', { token });
+        return { err: errors.InvalidToken };
+    }
+
+    const signedHeaders = authParams.signedHeaders!;
+    const signatureFromRequest = authParams.signatureFromRequest!;
+    const timestamp = authParams.timestamp!;
+    const expiry = authParams.expiry!;
+    const credential = authParams.credential!;
+
+    if (!areSignedHeadersComplete(signedHeaders, request.headers)) {
+        log.debug('signedHeaders are incomplete', { signedHeaders });
+        return { err: errors.AccessDenied };
+    }
+
+    const validationResult = validateCredentials(credential, timestamp,
+        log);
+    if (validationResult instanceof Error) {
+        log.debug('credentials in improper format', { credential,
+            timestamp, validationResult });
+        return { err: validationResult };
+    }
+    const accessKey = credential[0];
+    const scopeDate = credential[1];
+    const region = credential[2];
+    const service = credential[3];
+    const requestType = credential[4];
+
+    const isTimeSkewed = checkTimeSkew(timestamp, expiry, log);
+    if (isTimeSkewed) {
+        return { err: errors.RequestTimeTooSkewed };
+    }
+
+    let proxyPath: string | undefined;
+    if (request.headers.proxy_path) {
+        try {
+            proxyPath = decodeURIComponent(request.headers.proxy_path);
+        } catch (err) {
+            log.debug('invalid proxy_path header', { proxyPath });
+            return { err: errors.InvalidArgument.customizeDescription(
+                'invalid proxy_path header') };
+        }
+    }
+
+    // In query v4 auth, the canonical request needs
+    // to include the query params OTHER THAN
+    // the signature so create a
+    // copy of the query object and remove
+    // the X-Amz-Signature property.
+    const queryWithoutSignature = Object.assign({}, data);
+    delete queryWithoutSignature['X-Amz-Signature'];
+
+    // For query auth, instead of a
+    // checksum of the contents, the
+    // string 'UNSIGNED-PAYLOAD' should be
+    // added to the canonicalRequest in
+    // building string to sign
+    const payloadChecksum = 'UNSIGNED-PAYLOAD';
+
+    const stringToSign = constructStringToSign({
+        log,
+        request,
+        query: queryWithoutSignature,
+        signedHeaders,
+        payloadChecksum,
+        timestamp,
+        credentialScope:
+            `${scopeDate}/${region}/${service}/${requestType}`,
+        awsService: service,
+        proxyPath,
+    });
+    if (stringToSign instanceof Error) {
+        return { err: stringToSign };
+    }
+    log.trace('constructed stringToSign', { stringToSign });
+    return {
+        err: null,
+        params: {
+            version: 4,
+            data: {
+                accessKey,
+                signatureFromRequest,
+                region,
+                scopeDate,
+                stringToSign,
+                authType: 'REST-QUERY-STRING',
+                signatureVersion: 'AWS4-HMAC-SHA256',
+                signatureAge: Date.now() - convertAmzTimeToMs(timestamp),
+                securityToken: token,
+            },
+        },
+    };
+}

lib/auth/v4/streamingV4/V4Transform.ts

@@ -0,0 +1,316 @@
+import { Transform } from 'stream';
+import async from 'async';
+import errors from '../../../errors';
+import { Logger } from 'werelogs';
+import Vault, { AuthV4RequestParams } from '../../Vault';
+import { Callback } from '../../backends/in_memory/types';
+
+import constructChunkStringToSign from './constructChunkStringToSign';
+
+export type TransformParams = {
+    accessKey: string;
+    signatureFromRequest: string;
+    region: string;
+    scopeDate: string;
+    timestamp: string;
+    credentialScope: string;
+};
+
+/**
+ * This class is designed to handle the chunks sent in a streaming
+ * v4 Auth request
+ */
+export default class V4Transform extends Transform {
+    log: Logger;
+    cb: Callback;
+    accessKey: string;
+    region: string;
+    scopeDate: string;
+    timestamp: string;
+    credentialScope: string;
+    lastSignature: string;
+    currentSignature?: string;
+    haveMetadata: boolean;
+    seekingDataSize: number;
+    currentData?: any;
+    dataCursor: number;
+    currentMetadata: any[];
+    lastPieceDone: boolean;
+    lastChunk: boolean;
+    vault: Vault;
+
+    /**
+     * @constructor
+     * @param streamingV4Params - info for chunk authentication
+     * @param streamingV4Params.accessKey - requester's accessKey
+     * @param streamingV4Params.signatureFromRequest - signature
+     * sent with headers
+     * @param streamingV4Params.region - region sent with auth header
+     * @param streamingV4Params.scopeDate - date sent with auth header
+     * @param streamingV4Params.timestamp - date parsed from headers
+     * in ISO 8601 format: YYYYMMDDTHHMMSSZ
+     * @param streamingV4Params.credentialScope - items from auth
+     * header plus the string 'aws4_request' joined with '/':
+     * timestamp/region/aws-service/aws4_request
+     * @param vault - Vault instance passed from CloudServer
+     * @param log - logger object
+     * @param cb - callback to api
+     */
+    constructor(
+        streamingV4Params: TransformParams,
+        vault: Vault,
+        log: Logger,
+        cb: Callback,
+    ) {
+        const { accessKey, signatureFromRequest, region, scopeDate, timestamp,
+            credentialScope } = streamingV4Params;
+        super({});
+        this.log = log;
+        this.cb = cb;
+        this.accessKey = accessKey;
+        this.region = region;
+        this.scopeDate = scopeDate;
+        this.timestamp = timestamp;
+        this.credentialScope = credentialScope;
+        this.lastSignature = signatureFromRequest;
+        this.currentSignature = undefined;
+        this.haveMetadata = false;
+        // keep this as -1 to start since a seekingDataSize of 0
+        // means that chunk is just metadata (as is the case with the
+        // last chunk)
+        this.seekingDataSize = -1;
+        this.currentData = undefined;
+        this.dataCursor = 0;
+        this.currentMetadata = [];
+        this.lastPieceDone = false;
+        this.lastChunk = false;
+        this.vault = vault;
+    }
+
+    /**
+     * This function will parse the metadata portion of the chunk
+     * @param remainingChunk - chunk sent from _transform
+     * @return response - if error, will return 'err' key with
+     * arsenal error value.
+     * if incomplete metadata, will return 'completeMetadata' key with
+     * value false
+     * if complete metadata received, will return 'completeMetadata' key with
+     * value true and the key 'unparsedChunk' with the remaining chunk without
+     * the parsed metadata piece
+     */
+    _parseMetadata(remainingChunk: Buffer) {
+        let remainingPlusStoredMetadata = remainingChunk;
+        // have metadata pieces so need to add to the front of
+        // remainingChunk
+        if (this.currentMetadata.length > 0) {
+            this.currentMetadata.push(remainingChunk);
+            remainingPlusStoredMetadata = Buffer.concat(this.currentMetadata);
+            // zero out stored metadata
+            this.currentMetadata.length = 0;
+        }
+        let lineBreakIndex = remainingPlusStoredMetadata.indexOf('\r\n');
+        if (lineBreakIndex < 0) {
+            this.currentMetadata.push(remainingPlusStoredMetadata);
+            return { completeMetadata: false };
+        }
+        let fullMetadata = remainingPlusStoredMetadata.slice(0,
+            lineBreakIndex);
+
+        // handle extra line break on end of data chunk
+        if (fullMetadata.length === 0) {
+            const chunkWithoutLeadingLineBreak = remainingPlusStoredMetadata
+                .slice(2);
+            // find second line break
+            lineBreakIndex = chunkWithoutLeadingLineBreak.indexOf('\r\n');
+            if (lineBreakIndex < 0) {
+                this.currentMetadata.push(chunkWithoutLeadingLineBreak);
+                return { completeMetadata: false };
+            }
+            fullMetadata = chunkWithoutLeadingLineBreak.slice(0,
+                lineBreakIndex);
+        }
+
+        const splitMeta = fullMetadata.toString().split(';');
+        this.log.trace('parsed full metadata for chunk', { splitMeta });
+        if (splitMeta.length !== 2) {
+            this.log.trace('chunk body did not contain correct ' +
+            'metadata format');
+            return { err: errors.InvalidArgument };
+        }
+        // chunk-size is sent in hex
+        const dataSize = Number.parseInt(splitMeta[0], 16);
+        if (Number.isNaN(dataSize)) {
+            this.log.trace('chunk body did not contain valid size');
+            return { err: errors.InvalidArgument };
+        }
+        let chunkSig = splitMeta[1];
+        if (!chunkSig || chunkSig.indexOf('chunk-signature=') < 0) {
+            this.log.trace('chunk body did not contain correct sig format');
+            return { err: errors.InvalidArgument };
+        }
+        chunkSig = chunkSig.replace('chunk-signature=', '');
+        this.currentSignature = chunkSig;
+        this.haveMetadata = true;
+        if (dataSize === 0) {
+            this.lastChunk = true;
+            return {
+                completeMetadata: true,
+            };
+        }
+        // + 2 to get \r\n at end
+        this.seekingDataSize = dataSize + 2;
+        this.currentData = Buffer.alloc(dataSize);
+
+        return {
+            completeMetadata: true,
+            // start slice at lineBreak plus 2 to remove line break at end of
+            // metadata piece since length of '\r\n' is 2
+            unparsedChunk: remainingPlusStoredMetadata
+                .slice(lineBreakIndex + 2),
+        };
+    }
+
+    /**
+     * Build the stringToSign and authenticate the chunk
+     * @param dataToSend - chunk sent from _transform or null
+     * if last chunk without data
+     * @param done - callback to _transform
+     * @return executes callback with err if applicable
+     */
+    _authenticate(dataToSend: Buffer | null, done: Callback) {
+        // use prior sig to construct new string to sign
+        const stringToSign = constructChunkStringToSign(this.timestamp,
+            this.credentialScope, this.lastSignature, dataToSend ?? undefined);
+        this.log.trace('constructed chunk string to sign',
+            { stringToSign });
+        // once used prior sig to construct string to sign, reassign
+        // lastSignature to current signature
+        this.lastSignature = this.currentSignature!;
+        const vaultParams: AuthV4RequestParams = {
+            log: this.log,
+            data: {
+                accessKey: this.accessKey,
+                signatureFromRequest: this.currentSignature!,
+                region: this.region,
+                scopeDate: this.scopeDate,
+                stringToSign,
+                // TODO FIXME This can not work
+                // @ts-expect-errors
+                timestamp: this.timestamp,
+                credentialScope: this.credentialScope,
+            },
+        };
+        return this.vault.authenticateV4Request(vaultParams, null, err => {
+            if (err) {
+                this.log.trace('err from vault on streaming v4 auth',
+                    { error: err, paramsSentToVault: vaultParams.data });
+                return done(err);
+            }
+            return done();
+        });
+    }
+
+
+    /**
+     * This function will parse the chunk into metadata and data,
+     * use the metadata to authenticate with vault and send the
+     * data on to be stored if authentication passes
+     *
+     * @param chunk - chunk from request body
+     * @param _encoding - Data encoding unused
+     * @param callback - Callback(err, justDataChunk, encoding)
+     * @return executes callback with err if applicable
+     */
+    _transform(chunk: Buffer, _encoding: string, callback: Callback) {
+        // 'chunk' here is the node streaming chunk
+        // transfer-encoding chunks should be of the format:
+        // string(IntHexBase(chunk-size)) + ";chunk-signature=" +
+        // signature + \r\n + chunk-data + \r\n
+        // Last transfer-encoding chunk will have size 0 and no chunk-data.
+
+        if (this.lastPieceDone) {
+            const slice = chunk.slice(0, 10);
+            this.log.trace('received chunk after end.' +
+            'See first 10 bytes of chunk',
+            { chunk: slice.toString() });
+            return callback();
+        }
+        let unparsedChunk = chunk;
+        let chunkLeftToEvaluate = true;
+        return async.whilst(
+            // test function
+            () => chunkLeftToEvaluate,
+            // async function
+            done => {
+                if (!this.haveMetadata) {
+                    this.log.trace('do not have metadata so calling ' +
+                    '_parseMetadata');
+                    // need to parse our metadata
+                    const parsedMetadataResults =
+                        this._parseMetadata(unparsedChunk);
+                    if (parsedMetadataResults.err) {
+                        return done(parsedMetadataResults.err);
+                    }
+                    // if do not have full metadata get next chunk
+                    if (!parsedMetadataResults.completeMetadata) {
+                        chunkLeftToEvaluate = false;
+                        return done();
+                    }
+                    // have metadata so reset unparsedChunk to remaining
+                    // without metadata piece
+                    // TODO Is that okay?
+                    // @ts-expect-errors
+                    unparsedChunk = parsedMetadataResults.unparsedChunk;
+                }
+                if (this.lastChunk) {
+                    this.log.trace('authenticating final chunk with no data');
+                    return this._authenticate(null, err => {
+                        if (err) {
+                            return done(err);
+                        }
+                        chunkLeftToEvaluate = false;
+                        this.lastPieceDone = true;
+                        return done();
+                    });
+                }
+                if (unparsedChunk.length < this.seekingDataSize) {
+                    // add chunk to currentData and get next chunk
+                    unparsedChunk.copy(this.currentData, this.dataCursor);
+                    this.dataCursor += unparsedChunk.length;
+                    this.seekingDataSize -= unparsedChunk.length;
+                    chunkLeftToEvaluate = false;
+                    return done();
+                }
+                // parse just the next data piece without \r\n at the end
+                // (therefore, minus 2)
+                const nextDataPiece =
+                    unparsedChunk.slice(0, this.seekingDataSize - 2);
+                // add parsed data piece to other currentData pieces
+                // so that this.currentData is the full data piece
+                nextDataPiece.copy(this.currentData, this.dataCursor);
+                return this._authenticate(this.currentData, err => {
+                    if (err) {
+                        return done(err);
+                    }
+                    unparsedChunk =
+                        unparsedChunk.slice(this.seekingDataSize);
+                    this.push(this.currentData);
+                    this.haveMetadata = false;
+                    this.seekingDataSize = -1;
+                    this.currentData = undefined;
+                    this.dataCursor = 0;
+                    chunkLeftToEvaluate = unparsedChunk.length > 0;
+                    return done();
+                });
+            },
+            // final callback
+            err => {
+                if (err) {
+                    return this.cb(err as any);
+                }
+                // get next chunk
+                return callback();
+            },
+        );
+    }
+}

lib/auth/v4/streamingV4/constructChunkStringToSign.ts

@@ -0,0 +1,35 @@
+import * as crypto from 'crypto';
+import * as constants from '../../../constants';
+
+/**
+ * Constructs stringToSign for chunk
+ * @param timestamp - date parsed from headers
+ * in ISO 8601 format: YYYYMMDDTHHMMSSZ
+ * @param credentialScope - items from auth
+ * header plus the string 'aws4_request' joined with '/':
+ * timestamp/region/aws-service/aws4_request
+ * @param lastSignature - signature from headers or prior chunk
+ * @param justDataChunk - data portion of chunk
+ * @returns stringToSign
+ */
+export default function constructChunkStringToSign(
+    timestamp: string,
+    credentialScope: string,
+    lastSignature: string,
+    justDataChunk?: Buffer | string,
+) {
+    let currentChunkHash: string;
+    // for last chunk, there will be no data, so use emptyStringHash
+    if (!justDataChunk) {
+        currentChunkHash = constants.emptyStringHash;
+    } else {
+        const hash = crypto.createHash('sha256');
+        const temp = justDataChunk instanceof Buffer
+            ? hash.update(justDataChunk)
+            : hash.update(justDataChunk, 'binary');
+        currentChunkHash = temp.digest('hex');
+    }
+    return `AWS4-HMAC-SHA256-PAYLOAD\n${timestamp}\n` +
+        `${credentialScope}\n${lastSignature}\n` +
+        `${constants.emptyStringHash}\n${currentChunkHash}`;
+}

lib/auth/v4/timeUtils.ts

@@ -0,0 +1,56 @@
+import { Logger } from 'werelogs';
+
+/**
+ * Convert timestamp to milliseconds since Unix Epoch
+ * @param timestamp of ISO8601Timestamp format without
+ * dashes or colons, e.g. 20160202T220410Z
+ */
+export function convertAmzTimeToMs(timestamp: string) {
+    const arr = timestamp.split('');
+    // Convert to YYYY-MM-DDTHH:mm:ss.sssZ
+    const ISO8601time = `${arr.slice(0, 4).join('')}-${arr[4]}${arr[5]}` +
+        `-${arr.slice(6, 11).join('')}:${arr[11]}${arr[12]}:${arr[13]}` +
+        `${arr[14]}.000Z`;
+    return Date.parse(ISO8601time);
+}
+
+/**
+ * Convert UTC timestamp to ISO 8601 timestamp
+ * @param timestamp of UTC form: Fri, 10 Feb 2012 21:34:55 GMT
+ * @return ISO8601 timestamp of form: YYYYMMDDTHHMMSSZ
+ */
+export function convertUTCtoISO8601(timestamp: string | number) {
+    // convert to ISO string: YYYY-MM-DDTHH:mm:ss.sssZ.
+    const converted = new Date(timestamp).toISOString();
+    // Remove "-"s and "."s and milliseconds
+    return converted.split('.')[0].replace(/-|:/g, '').concat('Z');
+}
+
+/**
+ * Check whether timestamp predates request or is too old
+ * @param timestamp of ISO8601Timestamp format without
+ * dashes or colons, e.g. 20160202T220410Z
+ * @param expiry - number of seconds signature should be valid
+ * @param log - log for request
+ * @return true if there is a time problem
+ */
+export function checkTimeSkew(timestamp: string, expiry: number, log: Logger) {
+    const currentTime = Date.now();
+    const fifteenMinutes = (15 * 60 * 1000);
+    const parsedTimestamp = convertAmzTimeToMs(timestamp);
+    if ((currentTime + fifteenMinutes) < parsedTimestamp) {
+        log.debug('current time pre-dates timestamp', {
+            parsedTimestamp,
+            currentTimeInMilliseconds: currentTime });
+        return true;
+    }
+    const expiryInMilliseconds = expiry * 1000;
+    if (currentTime > parsedTimestamp + expiryInMilliseconds) {
+        log.debug('signature has expired', {
+            parsedTimestamp,
+            expiry,
+            currentTimeInMilliseconds: currentTime });
+        return true;
+    }
+    return false;
+}

lib/auth/v4/validateInputs.ts

@@ -0,0 +1,206 @@
+import { Logger } from 'werelogs';
+import errors from '../../../lib/errors';
+
+/**
+ * Validate Credentials
+ * @param credentials - contains accessKey, scopeDate,
+ * region, service, requestType
+ * @param timestamp - timestamp from request in
+ * the format of ISO 8601: YYYYMMDDTHHMMSSZ
+ * @param log - logging object
+ */
+export function validateCredentials(
+    credentials: [string, string, string, string, string],
+    timestamp: string,
+    log: Logger
+): Error | {} {
+    if (!Array.isArray(credentials) || credentials.length !== 5) {
+        log.warn('credentials in improper format', { credentials });
+        return errors.InvalidArgument;
+    }
+    // credentials[2] (region) is not read intentionally
+    const accessKey = credentials[0];
+    const scopeDate = credentials[1];
+    const service = credentials[3];
+    const requestType = credentials[4];
+    if (accessKey.length < 1) {
+        log.warn('accessKey provided is wrong format', { accessKey });
+        return errors.InvalidArgument;
+    }
+    // The scope date (format YYYYMMDD) must be same date as the timestamp
+    // on the request from the x-amz-date param (if queryAuthCheck)
+    // or from the x-amz-date header or date header (if headerAuthCheck)
+    // Format of timestamp is ISO 8601: YYYYMMDDTHHMMSSZ.
+    // http://docs.aws.amazon.com/AmazonS3/latest/API/
+    // sigv4-query-string-auth.html
+    // http://docs.aws.amazon.com/general/latest/gr/
+    // sigv4-date-handling.html
+
+    // convert timestamp to format of scopeDate YYYYMMDD
+    const timestampDate = timestamp.split('T')[0];
+    if (scopeDate.length !== 8 || scopeDate !== timestampDate) {
+        log.warn('scope date must be the same date as the timestamp date',
+            { scopeDate, timestampDate });
+        return errors.RequestTimeTooSkewed;
+    }
+    if (service !== 's3' && service !== 'iam' && service !== 'ring' &&
+        service !== 'sts') {
+        log.warn('service in credentials is not one of s3/iam/ring/sts', {
+            service,
+        });
+        return errors.InvalidArgument;
+    }
+    if (requestType !== 'aws4_request') {
+        log.warn('requestType contained in params is not aws4_request',
+            { requestType });
+        return errors.InvalidArgument;
+    }
+    return {};
+}
+
+/**
+ * Extract and validate components from query object
+ * @param  queryObj - query object from request
+ * @param log - logging object
+ * @return object containing extracted query params for authV4
+ */
+export function extractQueryParams(
+    queryObj: { [key: string]: string | undefined },
+    log: Logger
+) {
+    const authParams: {
+        signedHeaders?: string;
+        signatureFromRequest?: string;
+        timestamp?: string;
+        expiry?: number;
+        credential?: [string, string, string, string, string];
+    } = {};
+
+    // Do not need the algorithm sent back
+    if (queryObj['X-Amz-Algorithm'] !== 'AWS4-HMAC-SHA256') {
+        log.warn('algorithm param incorrect',
+            { algo: queryObj['X-Amz-Algorithm'] });
+        return authParams;
+    }
+
+    const signedHeaders = queryObj['X-Amz-SignedHeaders'];
+    // At least "host" must be included in signed headers
+    if (signedHeaders && signedHeaders.length > 3) {
+        authParams.signedHeaders = signedHeaders;
+    } else {
+        log.warn('missing signedHeaders');
+        return authParams;
+    }
+
+
+    const signature = queryObj['X-Amz-Signature'];
+    if (signature && signature.length === 64) {
+        authParams.signatureFromRequest = signature;
+    } else {
+        log.warn('missing signature');
+        return authParams;
+    }
+
+    const timestamp = queryObj['X-Amz-Date'];
+    if (timestamp && timestamp.length === 16) {
+        authParams.timestamp = timestamp;
+    } else {
+        log.warn('missing or invalid timestamp',
+            { timestamp: queryObj['X-Amz-Date'] });
+        return authParams;
+    }
+
+    const expiry = Number.parseInt(queryObj['X-Amz-Expires'] ?? 'nope', 10);
+    const sevenDays = 604800;
+    if (expiry && (expiry > 0 && expiry <= sevenDays)) {
+        authParams.expiry = expiry;
+    } else {
+        log.warn('invalid expiry', { expiry });
+        return authParams;
+    }
+
+    const credential = queryObj['X-Amz-Credential'];
+    if (credential && credential.length > 28 && credential.indexOf('/') > -1) {
+        // @ts-ignore
+        authParams.credential = credential.split('/');
+    } else {
+        log.warn('invalid credential param', { credential });
+        return authParams;
+    }
+    return authParams;
+}
+
+
+/**
+ * Extract and validate components from auth header
+ * @param authHeader - authorization header from request
+ * @param log - logging object
+ * @return object containing extracted auth header items for authV4
+ */
+export function extractAuthItems(authHeader: string, log: Logger) {
+    const authItems: {
+        credentialsArr?: [string, string, string, string, string];
+        signedHeaders?: string;
+        signatureFromRequest?: string;
+    } = {};
+    const authArray = authHeader.replace('AWS4-HMAC-SHA256 ', '').split(',');
+
+    if (authArray.length < 3) {
+        return authItems;
+    }
+    // extract authorization components
+    const credentialStr = authArray[0];
+    const signedHeadersStr = authArray[1];
+    const signatureStr = authArray[2];
+    log.trace('credentials from request', { credentialStr });
+    if (
+        credentialStr &&
+        credentialStr.trim().startsWith('Credential=') &&
+        credentialStr.indexOf('/') > -1
+    ) {
+        // @ts-ignore
+        authItems.credentialsArr = credentialStr
+            .trim().replace('Credential=', '').split('/');
+    } else {
+        log.warn('missing credentials');
+    }
+    log.trace('signed headers from request', { signedHeadersStr });
+    if (signedHeadersStr && signedHeadersStr.trim()
+        .startsWith('SignedHeaders=')) {
+        authItems.signedHeaders = signedHeadersStr
+            .trim().replace('SignedHeaders=', '');
+    } else {
+        log.warn('missing signed headers');
+    }
+    log.trace('signature from request', { signatureStr });
+    if (signatureStr && signatureStr.trim().startsWith('Signature=')) {
+        authItems.signatureFromRequest = signatureStr
+            .trim().replace('Signature=', '');
+    } else {
+        log.warn('missing signature');
+    }
+    return authItems;
+}
+
+/**
+ * Checks whether the signed headers include the host header
+ * and all x-amz- and x-scal- headers in request
+ * @param signedHeaders - signed headers sent with request
+ * @param allHeaders - request.headers
+ * @return true if all x-amz-headers included and false if not
+ */
+export function areSignedHeadersComplete(signedHeaders: string, allHeaders: Headers) {
+    const signedHeadersList = signedHeaders.split(';');
+    if (signedHeadersList.indexOf('host') === -1) {
+        return false;
+    }
+    const headers = Object.keys(allHeaders);
+    for (let i = 0; i < headers.length; i++) {
+        if ((headers[i].startsWith('x-amz-')
+        || headers[i].startsWith('x-scal-'))
+        && signedHeadersList.indexOf(headers[i]) === -1) {
+            return false;
+        }
+    }
+    return true;
+}

lib/clustering/ClusterRPC.ts

@@ -0,0 +1,569 @@
+import cluster, { Worker } from 'cluster';
+import * as werelogs from 'werelogs';
+
+import { default as errors } from '../../lib/errors';
+
+const rpcLogger = new werelogs.Logger('ClusterRPC');
+
+/**
+ * Remote procedure calls support between cluster workers.
+ *
+ * When using the cluster module, new processes are forked and are
+ * dispatched workloads, usually HTTP requests. The ClusterRPC module
+ * implements a RPC system to send commands to all cluster worker
+ * processes at once from any particular worker, and retrieve their
+ * individual command results, like a distributed map operation.
+ *
+ * The existing nodejs cluster IPC channel is setup from the primary
+ * to each worker, but not between workers, so there has to be a hop
+ * by the primary.
+ *
+ * How a command is treated:
+ *
+ * - a worker sends a command message to the primary
+ *
+ * - the primary then forwards that command to each existing worker
+ *   (including the requestor)
+ *
+ * - each worker then executes the command and returns a result or an
+ *   error
+ *
+ * - the primary gathers all workers results into an array
+ *
+ * - finally, the primary dispatches the results array to the original
+ *   requesting worker
+ *
+ *
+ * Limitations:
+ *
+ * - The command payload must be serializable, which means that:
+ *   - it should not contain circular references
+ *   - it should be of a reasonable size to be sent in a single RPC message
+ *
+ * - The "toWorkers" parameter of value "*" targets the set of workers
+ *   that are available at the time the command is dispatched. Any new
+ *   worker spawned after the command has been dispatched for
+ *   processing, but before the command completes, don't execute
+ *   the command and hence are not part of the results array.
+ *
+ *
+ * To set it up:
+ *
+ * - On the primary:
+ *     if (cluster.isPrimary) {
+ *         setupRPCPrimary();
+ *     }
+ *
+ * - On the workers:
+ *     if (!cluster.isPrimary) {
+ *         setupRPCWorker({
+ *             handler1: (payload: object, uids: string, callback: HandlerCallback) => void,
+ *             handler2: ...
+ *         });
+ *     }
+ *     Handler functions will be passed the command payload, request
+ *     serialized uids, and must call the callback when the worker is done
+ *     processing the command:
+ *         callback(error: Error | null | undefined, result?: any)
+ *
+ * When this setup is done, any worker can start sending commands by calling
+ * the async function sendWorkerCommand().
+ */
+
+// exported types
+
+export type ResultObject = {
+    error: Error | null;
+    result: any;
+};
+
+/**
+ * saved Promise for sendWorkerCommand
+ */
+export type CommandPromise = {
+    resolve: (results?: ResultObject[]) => void;
+    reject: (error: Error) => void;
+    timeout: NodeJS.Timeout | null;
+};
+export type HandlerCallback = (error: (Error & { code?: number }) | null | undefined, result?: any) => void;
+export type HandlerFunction = (payload: object, uids: string, callback: HandlerCallback) => void;
+export type HandlersMap = {
+    [index: string]: HandlerFunction;
+};
+export type PrimaryHandlerFunction = (worker: Worker, payload: object, uids: string, callback: HandlerCallback) => void;
+export type PrimaryHandlersMap = Record<string, PrimaryHandlerFunction>;
+
+// private types
+
+type RPCMessage<T extends string, P> = {
+    type: T;
+    uids: string;
+    payload: P;
+};
+
+type RPCCommandMessage = RPCMessage<'cluster-rpc:command', any> & {
+    toWorkers: string;
+    toHandler: string;
+};
+
+type MarshalledResultObject = {
+    error: string | null;
+    errorCode?: number;
+    result: any;
+};
+
+type RPCCommandResultMessage = RPCMessage<'cluster-rpc:commandResult', MarshalledResultObject>;
+
+type RPCCommandResultsMessage = RPCMessage<'cluster-rpc:commandResults', {
+    results: MarshalledResultObject[];
+}>;
+
+type RPCCommandErrorMessage = RPCMessage<'cluster-rpc:commandError', {
+    error: string;
+}>;
+
+interface RPCSetupOptions {
+    /**
+     * As werelogs is not a peerDependency, arsenal and a parent project
+     * might have their own separate versions duplicated in dependencies.
+     * The config are therefore not shared.
+     * Use this to propagate werelogs config to arsenal's ClusterRPC.
+     */
+    werelogsConfig?: Parameters<typeof werelogs.configure>[0];
+};
+
+/**
+ * In primary: store worker IDs that are waiting to be dispatched
+ * their command's results, as a mapping.
+ */
+const uidsToWorkerId: {
+    [index: string]: number;
+} = {};
+
+
+/**
+ * In primary: store worker responses for commands in progress as a
+ * mapping.
+ *
+ * Result objects are 'null' while the worker is still processing the
+ * command. When a worker finishes processing it stores the result as:
+ *    {
+ *        error: string | null,
+ *        result: any
+ *    }
+ */
+const uidsToCommandResults: {
+    [index: string]: {
+        [index: number]: MarshalledResultObject | null;
+    };
+} = {};
+
+/**
+ * In workers: store promise callbacks for commands waiting to be
+ * dispatched, as a mapping.
+ */
+const uidsToCommandPromise: {
+    [index: string]: CommandPromise;
+} = {};
+
+
+function _isRpcMessage(message) {
+    return (message !== null &&
+            typeof message === 'object' &&
+            typeof message.type === 'string' &&
+            message.type.startsWith('cluster-rpc:'));
+}
+
+/**
+ * Setup cluster RPC system on the primary
+ *
+ * @param {object} [handlers] - mapping of handler names to handler functions
+ *     handler function:
+ *         `handler({Worker} worker, {object} payload, {string} uids, {function} callback)`
+ *     handler callback must be called when worker is done with the command:
+ *         `callback({Error|null} error, {any} [result])`
+ * @return {undefined}
+ */
+export function setupRPCPrimary(handlers?: PrimaryHandlersMap, options?: RPCSetupOptions) {
+    if (options?.werelogsConfig) {
+        werelogs.configure(options.werelogsConfig);
+    }
+    cluster.on('message', (worker, message) => {
+        if (_isRpcMessage(message)) {
+            _handlePrimaryMessage(worker, message, handlers);
+        }
+    });
+}
+
+/**
+ * Setup RPCs on a cluster worker process
+ *
+ * @param {object} handlers - mapping of handler names to handler functions
+ *     handler function:
+ *         handler({object} payload, {string} uids, {function} callback)
+ *     handler callback must be called when worker is done with the command:
+ *         callback({Error|null} error, {any} [result])
+ * @return {undefined}
+ * }
+ */
+export function setupRPCWorker(handlers: HandlersMap, options?: RPCSetupOptions) {
+    if (!process.send) {
+        throw new Error('fatal: cannot setup cluster RPC: "process.send" is not available');
+    }
+    if (options?.werelogsConfig) {
+        werelogs.configure(options.werelogsConfig);
+    }
+    process.on('message', (message: RPCCommandMessage | RPCCommandResultsMessage) => {
+        if (_isRpcMessage(message)) {
+            _handleWorkerMessage(message, handlers);
+        }
+    });
+}
+
+/**
+ * Send a command for workers to execute in parallel, and wait for results
+ *
+ * @param {string} toWorkers - which workers should execute the command
+ *     Currently the supported values are:
+ *         - "*", meaning all workers will execute the command
+ *         - "PRIMARY", meaning primary process will execute the command
+ * @param {string} toHandler - name of handler that will execute the
+ * command in workers, as declared in setupRPCWorker() parameter object
+ * @param {string} uids - unique identifier of the command, must be
+ * unique across all commands in progress
+ * @param {object} payload - message payload, sent as-is to the handler
+ * @param {number} [timeoutMs=60000] - timeout the command with a
+ * "RequestTimeout" error after this number of milliseconds - set to 0
+ * to disable timeouts (the command may then hang forever)
+ * @returns {Promise}
+ */
+export async function sendWorkerCommand(
+    toWorkers: string,
+    toHandler: string,
+    uids: string,
+    payload: object,
+    timeoutMs: number = 60000
+) {
+    if (typeof uids !== 'string') {
+        rpcLogger.error('missing or invalid "uids" field', { uids });
+        throw errors.MissingParameter;
+    }
+    if (uidsToCommandPromise[uids] !== undefined) {
+        rpcLogger.error('a command is already in progress with same uids', { uids });
+        throw errors.OperationAborted;
+    }
+    rpcLogger.info('sending command', { toWorkers, toHandler, uids, payload });
+    return new Promise((resolve, reject) => {
+        let timeout: NodeJS.Timeout | null = null;
+        if (timeoutMs) {
+            timeout = setTimeout(() => {
+                delete uidsToCommandPromise[uids];
+                reject(errors.RequestTimeout);
+            }, timeoutMs);
+        }
+        uidsToCommandPromise[uids] = { resolve, reject, timeout };
+        const message: RPCCommandMessage = {
+            type: 'cluster-rpc:command',
+            toWorkers,
+            toHandler,
+            uids,
+            payload,
+        };
+        return process.send?.(message);
+    });
+}
+
+/**
+ * Get the number of commands in flight
+ * @returns {number}
+ */
+export function getPendingCommandsCount() {
+    return Object.keys(uidsToCommandPromise).length;
+}
+
+
+function _dispatchCommandResultsToWorker(
+    worker: Worker,
+    uids: string,
+    resultsArray: MarshalledResultObject[]
+): void {
+    const message: RPCCommandResultsMessage = {
+        type: 'cluster-rpc:commandResults',
+        uids,
+        payload: {
+            results: resultsArray,
+        },
+    };
+    worker.send(message);
+}
+
+function _dispatchCommandErrorToWorker(
+    worker: Worker,
+    uids: string,
+    error: Error,
+): void {
+    const message: RPCCommandErrorMessage = {
+        type: 'cluster-rpc:commandError',
+        uids,
+        payload: {
+            error: error.message,
+        },
+    };
+    worker.send(message);
+}
+
+function _sendPrimaryCommandResult(
+    worker: Worker,
+    uids: string,
+    error: (Error & { code?: number }) | null | undefined,
+    result?: any
+): void {
+    const message: RPCCommandResultsMessage = {
+        type: 'cluster-rpc:commandResults',
+        uids,
+        payload: {
+            results: [{ error: error?.message || null, errorCode: error?.code, result }],
+        },
+    };
+    worker.send?.(message);
+}
+
+function _handlePrimaryCommandMessage(
+    fromWorker: Worker,
+    logger: any,
+    message: RPCCommandMessage,
+    handlers?: PrimaryHandlersMap
+): void {
+    const { toWorkers, toHandler, uids, payload } = message;
+    if (toWorkers === '*') {
+        if (uidsToWorkerId[uids] !== undefined) {
+            logger.warn('new command already has a waiting worker with same uids', {
+                uids, workerId: uidsToWorkerId[uids],
+            });
+            return undefined;
+        }
+        const commandResults = {};
+        for (const workerId of Object.keys(cluster.workers || {})) {
+            commandResults[workerId] = null;
+        }
+        uidsToWorkerId[uids] = fromWorker?.id;
+        uidsToCommandResults[uids] = commandResults;
+
+        for (const [workerId, worker] of Object.entries(cluster.workers || {})) {
+            logger.debug('sending command message to worker', {
+                workerId, toHandler, payload,
+            });
+            if (worker) {
+                worker.send(message);
+            }
+        }
+    } else if (toWorkers === 'PRIMARY') {
+        const { toHandler, uids, payload } = message;
+        const cb: HandlerCallback = (err, result) => _sendPrimaryCommandResult(fromWorker, uids, err, result);
+
+        if (toHandler in (handlers || {})) {
+            return handlers![toHandler](fromWorker, payload, uids, cb);
+        }
+        logger.error('no such handler in "toHandler" field from worker command message', {
+            toHandler,
+        });
+        return cb(errors.NotImplemented);
+    } else {
+        logger.error('unsupported "toWorkers" field from worker command message', {
+            toWorkers,
+        });
+        if (fromWorker) {
+            _dispatchCommandErrorToWorker(fromWorker, uids, errors.NotImplemented);
+        }
+    }
+}
+
+function _handlePrimaryCommandResultMessage(
+    fromWorkerId: number,
+    logger: any,
+    message: RPCCommandResultMessage
+): void {
+    const { uids, payload } = message;
+    const commandResults = uidsToCommandResults[uids];
+    if (!commandResults) {
+        logger.warn('received command response message from worker for command not in flight', {
+            workerId: fromWorkerId,
+            uids,
+        });
+        return undefined;
+    }
+    if (commandResults[fromWorkerId] === undefined) {
+        logger.warn('received command response message with unexpected worker ID', {
+            workerId: fromWorkerId,
+            uids,
+        });
+        return undefined;
+    }
+    if (commandResults[fromWorkerId] !== null) {
+        logger.warn('ignoring duplicate command response from worker', {
+            workerId: fromWorkerId,
+            uids,
+        });
+        return undefined;
+    }
+    commandResults[fromWorkerId] = payload;
+    const commandResultsArray = Object.values(commandResults);
+    if (commandResultsArray.every(response => response !== null)) {
+        logger.debug('all workers responded to command', { uids });
+        const completeCommandResultsArray = <MarshalledResultObject[]> commandResultsArray;
+        const toWorkerId = uidsToWorkerId[uids];
+        const toWorker = cluster.workers?.[toWorkerId];
+
+        delete uidsToCommandResults[uids];
+        delete uidsToWorkerId[uids];
+
+        if (!toWorker) {
+            logger.warn('worker shut down while its command was executing', {
+                workerId: toWorkerId, uids,
+            });
+            return undefined;
+        }
+        // send back response to original worker
+        _dispatchCommandResultsToWorker(toWorker, uids, completeCommandResultsArray);
+    }
+}
+
+function _handlePrimaryMessage(
+    fromWorker: Worker,
+    message: RPCCommandMessage | RPCCommandResultMessage,
+    handlers?: PrimaryHandlersMap
+): void {
+    const { type: messageType, uids } = message;
+    const logger = rpcLogger.newRequestLoggerFromSerializedUids(uids);
+    logger.debug('primary received message from worker', {
+        workerId: fromWorker?.id, rpcMessage: message,
+    });
+    if (messageType === 'cluster-rpc:command') {
+        return _handlePrimaryCommandMessage(fromWorker, logger, message, handlers);
+    }
+    if (messageType === 'cluster-rpc:commandResult') {
+        return _handlePrimaryCommandResultMessage(fromWorker?.id, logger, message);
+    }
+    logger.error('unsupported message type', {
+        workerId: fromWorker?.id, messageType, uids,
+    });
+    return undefined;
+}
+
+function _sendWorkerCommandResult(
+    uids: string,
+    error: Error | null | undefined,
+    result?: any
+): void {
+    const message: RPCCommandResultMessage = {
+        type: 'cluster-rpc:commandResult',
+        uids,
+        payload: {
+            error: error ? error.message : null,
+            result,
+        },
+    };
+    process.send?.(message);
+}
+
+function _handleWorkerCommandMessage(
+    logger: any,
+    message: RPCCommandMessage,
+    handlers: HandlersMap
+): void {
+    const { toHandler, uids, payload } = message;
+    const cb: HandlerCallback = (err, result) => _sendWorkerCommandResult(uids, err, result);
+
+    if (toHandler in handlers) {
+        return handlers[toHandler](payload, uids, cb);
+    }
+    logger.error('no such handler in "toHandler" field from worker command message', {
+        toHandler,
+    });
+    return cb(errors.NotImplemented);
+}
+
+function _handleWorkerCommandResultsMessage(
+    logger: any,
+    message: RPCCommandResultsMessage,
+): void {
+    const { uids, payload } = message;
+    const { results } = payload;
+    const commandPromise: CommandPromise = uidsToCommandPromise[uids];
+    if (commandPromise === undefined) {
+        logger.error('missing promise for command results', { uids, payload });
+        return undefined;
+    }
+    if (commandPromise.timeout) {
+        clearTimeout(commandPromise.timeout);
+    }
+    delete uidsToCommandPromise[uids];
+    const unmarshalledResults = results.map(workerResult => {
+        let workerError: Error | null = null;
+        if (workerResult.error) {
+            if (workerResult.error in errors) {
+                workerError = errors[workerResult.error];
+            } else {
+                workerError = new Error(workerResult.error);
+            }
+        }
+        if (workerError && workerResult.errorCode) {
+            (workerError as Error & { code: number }).code = workerResult.errorCode;
+        }
+        const unmarshalledResult: ResultObject = {
+            error: workerError,
+            result: workerResult.result,
+        };
+        return unmarshalledResult;
+    });
+    return commandPromise.resolve(unmarshalledResults);
+}
+
+function _handleWorkerCommandErrorMessage(
+    logger: any,
+    message: RPCCommandErrorMessage,
+): void {
+    const { uids, payload } = message;
+    const { error } = payload;
+    const commandPromise: CommandPromise = uidsToCommandPromise[uids];
+    if (commandPromise === undefined) {
+        logger.error('missing promise for command results', { uids, payload });
+        return undefined;
+    }
+    if (commandPromise.timeout) {
+        clearTimeout(commandPromise.timeout);
+    }
+    delete uidsToCommandPromise[uids];
+    let commandError: Error | null = null;
+    if (error in errors) {
+        commandError = errors[error];
+    } else {
+        commandError = new Error(error);
+    }
+    return commandPromise.reject(<Error> commandError);
+}
+
+function _handleWorkerMessage(
+    message: RPCCommandMessage | RPCCommandResultsMessage | RPCCommandErrorMessage,
+    handlers: HandlersMap
+): void {
+    const { type: messageType, uids } = message;
+    const workerId = cluster.worker?.id;
+    const logger = rpcLogger.newRequestLoggerFromSerializedUids(uids);
+    logger.debug('worker received message from primary', {
+        workerId, rpcMessage: message,
+    });
+    if (messageType === 'cluster-rpc:command') {
+        return _handleWorkerCommandMessage(logger, message, handlers);
+    }
+    if (messageType === 'cluster-rpc:commandResults') {
+        return _handleWorkerCommandResultsMessage(logger, message);
+    }
+    if (messageType === 'cluster-rpc:commandError') {
+        return _handleWorkerCommandErrorMessage(logger, message);
+    }
+    logger.error('unsupported message type', {
+        workerId, messageType,
+    });
+    return undefined;
+}

lib/constants.ts

@@ -0,0 +1,177 @@
+import * as crypto from 'crypto';
+
+// The min value here is to manage further backward compat if we
+// need it
+// Default value
+export const vaultGeneratedIamSecurityTokenSizeMin = 128;
+// Safe to assume that a typical token size is less than 8192 bytes
+export const vaultGeneratedIamSecurityTokenSizeMax = 8192;
+// Base-64
+export const vaultGeneratedIamSecurityTokenPattern = /^[A-Za-z0-9/+=]*$/;
+
+// info about the iam security token
+export const iamSecurityToken = {
+    min: vaultGeneratedIamSecurityTokenSizeMin,
+    max: vaultGeneratedIamSecurityTokenSizeMax,
+    pattern: vaultGeneratedIamSecurityTokenPattern,
+};
+// PublicId is used as the canonicalID for a request that contains
+// no authentication information.  Requestor can access
+// only public resources
+export const publicId = 'http://acs.amazonaws.com/groups/global/AllUsers';
+export const zenkoServiceAccount = 'http://acs.zenko.io/accounts/service';
+export const metadataFileNamespace = '/MDFile';
+export const dataFileURL = '/DataFile';
+export const passthroughFileURL = '/PassthroughFile';
+// AWS states max size for user-defined metadata
+// (x-amz-meta- headers) is 2 KB:
+// http://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectPUT.html
+// In testing, AWS seems to allow up to 88 more bytes,
+// so we do the same.
+export const maximumMetaHeadersSize = 2136;
+export const emptyFileMd5 = 'd41d8cd98f00b204e9800998ecf8427e';
+// Version 2 changes the format of the data location property
+// Version 3 adds the dataStoreName attribute
+// Version 4 add the Creation-Time and Content-Language attributes,
+//     and add support for x-ms-meta-* headers in UserMetadata
+// Version 5 adds the azureInfo structure
+// Version 6 adds a "deleted" flag that is updated to true before
+// the object gets deleted. This is done to keep object metadata in the
+// oplog when deleting the object, as oplog deletion events don't contain
+// any metadata of the object.
+// version 6 also adds the "isPHD" flag that is used to indicate that the master
+// object is a placeholder and is not up to date.
+export const mdModelVersion = 6;
+/*
+ * Splitter is used to build the object name for the overview of a
+ * multipart upload and to build the object names for each part of a
+ * multipart upload.  These objects with large names are then stored in
+ * metadata in a "shadow bucket" to a real bucket.  The shadow bucket
+ * contains all ongoing multipart uploads.  We include in the object
+ * name some of the info we might need to pull about an open multipart
+ * upload or about an individual part with each piece of info separated
+ * by the splitter.  We can then extract each piece of info by splitting
+ * the object name string with this splitter.
+ * For instance, assuming a splitter of '...!*!',
+ * the name of the upload overview would be:
+ *   overview...!*!objectKey...!*!uploadId
+ * For instance, the name of a part would be:
+ *   uploadId...!*!partNumber
+ *
+ * The sequence of characters used in the splitter should not occur
+ * elsewhere in the pieces of info to avoid splitting where not
+ * intended.
+ *
+ * Splitter is also used in adding bucketnames to the
+ * namespacerusersbucket.  The object names added to the
+ * namespaceusersbucket are of the form:
+ * canonicalID...!*!bucketname
+ */
+
+export const splitter = '..|..';
+export const usersBucket = 'users..bucket';
+// MPU Bucket Prefix is used to create the name of the shadow
+// bucket used for multipart uploads.  There is one shadow mpu
+// bucket per bucket and its name is the mpuBucketPrefix followed
+// by the name of the final destination bucket for the object
+// once the multipart upload is complete.
+export const mpuBucketPrefix = 'mpuShadowBucket';
+// since aws s3 does not allow capitalized buckets, these may be
+// used for special internal purposes
+export const permittedCapitalizedBuckets = {
+    METADATA: true,
+};
+// Setting a lower object key limit to account for:
+// - Mongo key limit of 1012 bytes
+// - Version ID in Mongo Key if versioned of 33
+// - Max bucket name length if bucket match false of 63
+// - Extra prefix slash for bucket prefix if bucket match of 1
+export const objectKeyByteLimit = 915;
+/* delimiter for location-constraint. The location constraint will be able
+ * to include the ingestion flag
+ */
+export const zenkoSeparator = ':';
+/* eslint-disable camelcase */
+export const externalBackends = { aws_s3: true, azure: true, gcp: true, pfs: true };
+export const replicationBackends = { aws_s3: true, azure: true, gcp: true };
+// hex digest of sha256 hash of empty string:
+export const emptyStringHash = crypto.createHash('sha256')
+    .update('', 'binary').digest('hex');
+export const mpuMDStoredExternallyBackend = { aws_s3: true, gcp: true };
+// AWS sets a minimum size limit for parts except for the last part.
+// http://docs.aws.amazon.com/AmazonS3/latest/API/mpUploadComplete.html
+export const minimumAllowedPartSize = 5242880;
+export const gcpMaximumAllowedPartCount = 1024;
+// GCP Object Tagging Prefix
+export const gcpTaggingPrefix = 'aws-tag-';
+export const productName = 'APN/1.0 Scality/1.0 Scality CloudServer for Zenko';
+export const legacyLocations = ['sproxyd', 'legacy'];
+// healthcheck default call from nginx is every 2 seconds
+// for external backends, don't call unless at least 1 minute
+// (60,000 milliseconds) since last call
+export const externalBackendHealthCheckInterval = 60000;
+// some of the available data backends  (if called directly rather
+// than through the multiple backend gateway) need a key provided
+// as a string as first parameter of the get/delete methods.
+export const clientsRequireStringKey = { sproxyd: true, cdmi: true };
+export const hasCopyPartBackends = { aws_s3: true, gcp: true };
+export const versioningNotImplBackends = { azure: true, gcp: true };
+// user metadata applied on zenko-created objects
+export const zenkoIDHeader = 'x-amz-meta-zenko-instance-id';
+// Default expiration value of the S3 pre-signed URL duration
+// 604800 seconds (seven days).
+export const defaultPreSignedURLExpiry = 7 * 24 * 60 * 60;
+// Regex for ISO-8601 formatted date
+export const shortIso8601Regex = /\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z/;
+export const longIso8601Regex = /\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}.\d{3}Z/;
+export const supportedNotificationEvents = new Set([
+    's3:ObjectCreated:*',
+    's3:ObjectCreated:Put',
+    's3:ObjectCreated:Copy',
+    's3:ObjectCreated:CompleteMultipartUpload',
+    's3:ObjectRemoved:*',
+    's3:ObjectRemoved:Delete',
+    's3:ObjectRemoved:DeleteMarkerCreated',
+    's3:Replication:OperationFailedReplication',
+    's3:ObjectTagging:*',
+    's3:ObjectTagging:Put',
+    's3:ObjectTagging:Delete',
+    's3:ObjectAcl:Put',
+    's3:ObjectRestore:*',
+    's3:ObjectRestore:Post',
+    's3:ObjectRestore:Completed',
+    's3:ObjectRestore:Delete',
+    's3:LifecycleTransition',
+    's3:LifecycleExpiration:*',
+    's3:LifecycleExpiration:DeleteMarkerCreated',
+    's3:LifecycleExpiration:Delete',
+]);
+export const notificationArnPrefix = 'arn:scality:bucketnotif';
+// HTTP server keep-alive timeout is set to a higher value than
+// client's free sockets timeout to avoid the risk of triggering
+// ECONNRESET errors if the server closes the connection at the
+// exact moment clients attempt to reuse an established connection
+// for a new request.
+//
+// Note: the ability to close inactive connections on the client
+// after httpClientFreeSocketsTimeout milliseconds requires the
+// use of "agentkeepalive" module instead of the regular node.js
+// http.Agent.
+export const httpServerKeepAliveTimeout = 60000;
+export const httpClientFreeSocketTimeout = 55000;
+export const supportedLifecycleRules = [
+    'expiration',
+    'noncurrentVersionExpiration',
+    'abortIncompleteMultipartUpload',
+    'transitions',
+    'noncurrentVersionTransition',
+];
+// Maximum number of buckets to cache (bucket metadata)
+export const maxCachedBuckets = process.env.METADATA_MAX_CACHED_BUCKETS ?
+    Number(process.env.METADATA_MAX_CACHED_BUCKETS) : 1000;
+
+export const validRestoreObjectTiers = new Set(['Expedited', 'Standard', 'Bulk']);
+export const maxBatchingConcurrentOperations = 5;
+
+/** For policy resource arn check we allow empty account ID to not break compatibility */
+export const policyArnAllowedEmptyAccountId = ['utapi', 'scuba'];

lib/db.ts

@@ -0,0 +1,194 @@
+/**
+ * Like Error, but with a property set to true.
+ * TODO: this is copied from kineticlib, should consolidate with the
+ * future errors module
+ *
+ * Example: instead of:
+ *     const err = new Error("input is not a buffer");
+ *     err.badTypeInput = true;
+ *     throw err;
+ * use:
+ *     throw propError("badTypeInput", "input is not a buffer");
+ *
+ * @param propName - the property name.
+ * @param message - the Error message.
+ * @returns the Error object.
+ */
+function propError(propName: string, message: string): Error {
+    const err = new Error(message);
+    err[propName] = true;
+    // @ts-ignore
+    err.is = { [propName]: true };
+    return err;
+}
+
+/**
+ * Running transaction with multiple updates to be committed atomically
+ */
+export class IndexTransaction {
+    operations: { type: 'put' | 'del'; key: string; value?: any }[];
+    db: any;
+    closed: boolean;
+    conditions: { [key: string]: string }[];
+
+    /**
+     * Builds a new transaction
+     *
+     * @argument {Leveldb} db an open database to which the updates
+     *                     will be applied
+     *
+     * @returns a new empty transaction
+     */
+    constructor(db: any) {
+        this.operations = [];
+        this.db = db;
+        this.closed = false;
+        this.conditions = [];
+    }
+
+    /**
+     * Adds a new operation to participate in this running transaction
+     *
+     * @argument op an object with the following attributes:
+     *                    {
+     *                      type: 'put' or 'del',
+     *                      key: the object key,
+     *                      value: (optional for del) the value to store,
+     *                    }
+     *
+     * @throws an error described by the following properties
+     *                 - invalidTransactionVerb if op is not put or del
+     *                 - pushOnCommittedTransaction if already committed
+     *                 - missingKey if the key is missing from the op
+     *                 - missingValue if putting without a value
+     */
+    push(op: { type: 'put'; key: string; value: any }): void;
+    push(op: { type: 'del'; key: string }): void;
+    push(op: { type: 'put' | 'del'; key: string; value?: any }): void {
+        if (this.closed) {
+            throw propError(
+                'pushOnCommittedTransaction',
+                'can not add ops to already committed transaction'
+            );
+        }
+
+        if (op.type !== 'put' && op.type !== 'del') {
+            throw propError(
+                'invalidTransactionVerb',
+                `unknown action type: ${op.type}`
+            );
+        }
+
+        if (op.key === undefined) {
+            throw propError('missingKey', 'missing key');
+        }
+
+        if (op.type === 'put' && op.value === undefined) {
+            throw propError('missingValue', 'missing value');
+        }
+
+        this.operations.push(op);
+    }
+
+    /**
+     * Adds a new put operation to this running transaction
+     *
+     * @argument {string} key - the key of the object to put
+     * @argument {string} value - the value to put
+     *
+     * @throws {Error} an error described by the following properties
+     *                 - pushOnCommittedTransaction if already committed
+     *                 - missingKey if the key is missing from the op
+     *                 - missingValue if putting without a value
+     * @see push
+     */
+    put(key: string, value: any) {
+        this.push({ type: 'put', key, value });
+    }
+
+    /**
+     * Adds a new del operation to this running transaction
+     *
+     * @argument key - the key of the object to delete
+     *
+     * @throws an error described by the following properties
+     *                 - pushOnCommittedTransaction if already committed
+     *                 - missingKey if the key is missing from the op
+     *
+     * @see push
+     */
+    del(key: string) {
+        this.push({ type: 'del', key });
+    }
+
+    /**
+     * Adds a condition for the transaction
+     *
+     * @argument condition an object with the following attributes:
+     *                    {
+     *                      <condition>: the object key
+     *                    }
+     *                    example: { notExists: 'key1' }
+     *
+     * @throws an error described by the following properties
+     *                 - pushOnCommittedTransaction if already committed
+     *                 - missingCondition if the condition is empty
+     *
+     */
+    addCondition(condition: { [key: string]: string }) {
+        if (this.closed) {
+            throw propError(
+                'pushOnCommittedTransaction',
+                'can not add conditions to already committed transaction'
+            );
+        }
+        if (condition === undefined || Object.keys(condition).length === 0) {
+            throw propError(
+                'missingCondition',
+                'missing condition for conditional put'
+            );
+        }
+        if (typeof condition.notExists !== 'string' && typeof condition.exists !== 'string') {
+            throw propError(
+                'unsupportedConditionalOperation',
+                'missing key or supported condition'
+            );
+        }
+        this.conditions.push(condition);
+    }
+
+    /**
+     * Applies the queued updates in this transaction atomically.
+     *
+     * @argument cb function to be called when the commit
+     *              finishes, taking an optional error argument
+     *
+     */
+    commit(cb: (error: Error | null, data?: any) => void) {
+        if (this.closed) {
+            return cb(
+                propError(
+                    'alreadyCommitted',
+                    'transaction was already committed'
+                )
+            );
+        }
+
+        if (this.operations.length === 0) {
+            return cb(
+                propError(
+                    'emptyTransaction',
+                    'tried to commit an empty transaction'
+                )
+            );
+        }
+
+        this.closed = true;
+        const options = { sync: true, conditions: this.conditions };
+
+        // The array-of-operations variant of the `batch` method
+        // allows passing options such has `sync: true` whereas the
+        // chained form does not.
+        return this.db.batch(this.operations, options, cb);
+    }
+}

lib/errorUtils.ts

@@ -0,0 +1,11 @@
+export interface ErrorLike {
+    message: any;
+    code: any;
+    stack: any;
+    name: any;
+}
+
+export function reshapeExceptionError(error: ErrorLike) {
+    const { message, code, stack, name } = error;
+    return { message, code, stack, name };
+}

lib/errors/index.ts

@@ -0,0 +1,175 @@
+import type { ServerResponse } from 'http';
+import * as rawErrors from './arsenalErrors';
+
+/** All possible errors names. */
+export type Name = keyof typeof rawErrors;
+/** Object containing all errors names. It has the format { [Name]: "Name" } */
+export type Names = { [Name_ in Name]: Name_ };
+/** Mapping used to determine an error type. It has the format { [Name]: boolean } */
+export type Is = { [_ in Name]: boolean };
+/** Mapping of all possible Errors. It has the format { [Name]: Error } */
+export type Errors = { [_ in Name]: ArsenalError };
+
+// This object is reused constantly through createIs, we store it there
+// to avoid recomputation.
+const isBase = Object.fromEntries(
+    Object.keys(rawErrors).map((key) => [key, false])
+) as Is;
+
+// This allows to conditionally add the old behavior of errors to properly
+// test migration.
+// Activate CI tests with `ALLOW_UNSAFE_ERROR_COMPARISON=false yarn test`.
+// Remove this mechanism in ARSN-176.
+export const allowUnsafeErrComp = (
+    process.env.ALLOW_UNSAFE_ERROR_COMPARISON ?? 'true') === 'true'
+
+// This contains some metaprog. Be careful.
+// Proxy can be found on MDN.
+// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy
+// While this could seems better to avoid metaprog, this allows us to enforce
+// type-checking properly while avoiding all errors that could happen at runtime.
+// Even if some errors are made in JavaScript, like using err.is.NonExistingError,
+// the Proxy will return false.
+const createIs = (type: Name): Is => {
+    const get = (is: Is, value: string | symbol) => is[value] ?? false;
+    const final = Object.freeze({ ...isBase, [type]: true });
+    return new Proxy(final, { get });
+};
+
+export class ArsenalError extends Error {
+    /** HTTP status code. Example: 401, 403, 500, ... */
+    #code: number;
+    /** Text description of the error. */
+    #description: string;
+    /** Type of the error. */
+    #type: Name;
+    /** Object used to determine the error type.
+     * Example: error.is.InternalError */
+    #is: Is;
+    /** A map of error metadata (can be extra fields
+     * that only show in debug mode) */
+    #metadata: Map<string, Object[]>;
+
+    private constructor(type: Name, code: number, description: string,
+        metadata?: Map<string, Object[]>) {
+        super(type);
+        this.#code = code;
+        this.#description = description;
+        this.#type = type;
+        this.#is = createIs(type);
+        this.#metadata = metadata ?? new Map<string, Object[]>();
+
+        // This restores the old behavior of errors, to make sure they're now
+        // backward-compatible. Fortunately it's handled by TS, but it cannot
+        // be type-checked. This means we have to be extremely careful about
+        // what we're doing when using errors.
+        // Disables the feature when in CI tests but not in production.
+        if (allowUnsafeErrComp) {
+            this[type] = true;
+        }
+    }
+
+    /** Output the error as a JSON string */
+    toString() {
+        const errorType = this.message;
+        const errorMessage = this.#description;
+        return JSON.stringify({ errorType, errorMessage });
+    }
+
+    flatten() {
+        return {
+            is_arsenal_error: true,
+            code: this.#code,
+            description: this.#description,
+            type: this.#type,
+            stack: this.stack
+        }
+    }
+
+    static unflatten(flat_obj) {
+        if (!flat_obj.is_arsenal_error) {
+            return null;
+        }
+
+        const err = new ArsenalError(
+            flat_obj.type,
+            flat_obj.code,
+            flat_obj.description
+        )
+        err.stack = flat_obj.stack
+        return err;
+    }
+
+    /** Write the error in an HTTP response */
+    writeResponse(res: ServerResponse) {
+        res.writeHead(this.#code);
+        const asStr = this.toString();
+        res.end(asStr);
+    }
+
+    /** Clone the error with a new description.*/
+    customizeDescription(description: string): ArsenalError {
+        const type = this.#type;
+        const code = this.#code;
+        const metadata = new Map(this.#metadata);
+        const err = new ArsenalError(type, code, description, metadata);
+        err.stack = this.stack;
+        return err;
+    }
+
+    /** Clone the error with a new metadata field */
+    addMetadataEntry(key: string, value: Object[]): ArsenalError {
+        const type = this.#type;
+        const code = this.#code;
+        const description = this.#description;
+        const metadata = new Map(this.#metadata);
+        metadata.set(key, value);
+        const err = new ArsenalError(type, code, description, metadata);
+        err.stack = this.stack;
+        return err;
+    }
+
+    /** Used to determine the error type. Example: error.is.InternalError */
+    get is() {
+        return this.#is;
+    }
+
+    /** HTTP status code. Example: 401, 403, 500, ... */
+    get code() {
+        return this.#code;
+    }
+
+    /** Text description of the error. */
+    get description() {
+        return this.#description;
+    }
+
+    /**
+     * Type of the error, belonging to Name. is should be prefered instead of
+     * type in a daily-basis, but type remains accessible for future use. */
+    get type() {
+        return this.#type;
+    }
+
+    /** A map of error metadata */
+    get metadata() {
+        return this.#metadata;
+    }
+
+    /** Generate all possible errors. An instance is created by default. */
+    static errors() {
+        const errors = {};
+        Object.entries(rawErrors).forEach((value) => {
+            const name = value[0] as Name;
+            const error = value[1];
+            const { code, description } = error;
+            const get = () => new ArsenalError(name, code, description);
+            Object.defineProperty(errors, name, { get });
+        });
+        return errors as Errors;
+    }
+}
+
+/** Mapping of all possible Errors.
+ * Use them with errors[error].customizeDescription for any customization. */
+export default ArsenalError.errors();

lib/executables/pensieveCreds/README.md

@@ -0,0 +1,20 @@
+# Get Pensieve Credentials Executable
+
+## To make executable file from getPensieveCreds.js
+
+`npm install -g pkg`
+`pkg getPensieveCreds.js`
+
+This will build a mac, linux and windows file.
+If you just want linux, for example:
+`pkg getPensieveCreds.js --targets node6-linux-x64`
+
+For further options, see https://github.com/zeit/pkg
+
+## To run the executable file
+
+Call the output executable file with an
+argument that names the service you
+are trying to get credentials for (e.g., clueso):
+
+`./getPensieveCreds-linux serviceName`

lib/executables/pensieveCreds/getPensieveCreds.js

@@ -0,0 +1,45 @@
+const async = require('async');
+const MetadataFileClient =
+    require('../../storage/metadata/file/MetadataFileClient');
+const mdClient = new MetadataFileClient({
+    host: 's3-metadata',
+    port: '9993',
+});
+const { loadOverlayVersion, parseServiceCredentials } = require('./utils');
+
+const serviceName = process.argv[2];
+if (serviceName === undefined) {
+    throw new Error('Missing service name (e.g., clueso)');
+}
+const tokenKey = 'auth/zenko/remote-management-token';
+
+const mdDb = mdClient.openDB(error => {
+    if (error) {
+        throw error;
+    }
+
+    const db = mdDb.openSub('PENSIEVE');
+    return async.waterfall([
+        cb => db.get('configuration/overlay-version', {}, cb),
+        (version, cb) => loadOverlayVersion(db, version, cb),
+        (conf, cb) => db.get(tokenKey, {}, (err, instanceAuth) => {
+            if (err) {
+                return cb(err);
+            }
+            const creds = parseServiceCredentials(conf, instanceAuth,
+                serviceName);
+            return cb(null, creds);
+        }),
+    ], (err, creds) => {
+        db.disconnect();
+        if (err) {
+            throw err;
+        }
+        if (!creds) {
+            throw new Error('No credentials found');
+        }
+        process.stdout.write(`export AWS_ACCESS_KEY_ID="${creds.accessKey}"\n`);
+        process.stdout
+            .write(`export AWS_SECRET_ACCESS_KEY="${creds.secretKey}"`);
+    });
+});

lib/executables/pensieveCreds/package.json

@@ -0,0 +1,14 @@
+{
+  "name": "pensievecreds",
+  "version": "1.0.0",
+  "description": "Executable tool for Pensieve",
+  "main": "getPensieveCreds.js",
+  "scripts": {
+    "test": "mocha --recursive --timeout 5500 tests/unit"
+  },
+  "dependencies": {
+    "mocha": "5.2.0",
+    "async": "~2.6.1",
+    "node-forge": "^0.7.1"
+  }
+}

lib/executables/pensieveCreds/tests/resources.json

@@ -0,0 +1,7 @@
+{
+    "privateKey": "-----BEGIN RSA PRIVATE KEY-----\r\nMIIEowIBAAKCAQEAj13sSYE40lAX2qpBvfdGfcSVNtBf8i5FH+E8FAhORwwPu+2S\r\n3yBQbgwHq30WWxunGb1NmZL1wkVZ+vf12DtxqFRnMA08LfO4oO6oC4V8XfKeuHyJ\r\n1qlaKRINz6r9yDkTHtwWoBnlAINurlcNKgGD5p7D+G26Chbr/Oo0ZwHula9DxXy6\r\neH8/bJ5/BynyNyyWRPoAO+UkUdY5utkFCUq2dbBIhovMgjjikf5p2oWqnRKXc+JK\r\nBegr6lSHkkhyqNhTmd8+wA+8Cace4sy1ajY1t5V4wfRZea5vwl/HlyyKodvHdxng\r\nJgg6H61JMYPkplY6Gr9OryBKEAgq02zYoYTDfwIDAQABAoIBAAuDYGlavkRteCzw\r\nRU1LIVcSRWVcgIgDXTu9K8T0Ec0008Kkxomyn6LmxmroJbZ1VwsDH8s4eRH73ckA\r\nxrZxt6Pr+0lplq6eBvKtl8MtGhq1VDe+kJczjHEF6SQHOFAu/TEaPZrn2XMcGvRX\r\nO1BnRL9tepFlxm3u/06VRFYNWqqchM+tFyzLu2AuiuKd5+slSX7KZvVgdkY1ErKH\r\ngB75lPyhPb77C/6ptqUisVMSO4JhLhsD0+ekDVY982Sb7KkI+szdWSbtMx9Ek2Wo\r\ntXwJz7I8T7IbODy9aW9G+ydyhMDFmaEYIaDVFKJj5+fluNza3oQ5PtFNVE50GQJA\r\nsisGqfECgYEAwpkwt0KpSamSEH6qknNYPOwxgEuXWoFVzibko7is2tFPvY+YJowb\r\n68MqHIYhf7gHLq2dc5Jg1TTbGqLECjVxp4xLU4c95KBy1J9CPAcuH4xQLDXmeLzP\r\nJ2YgznRocbzAMCDAwafCr3uY9FM7oGDHAi5bE5W11xWx+9MlFExL3JkCgYEAvJp5\r\nf+JGN1W037bQe2QLYUWGszewZsvplnNOeytGQa57w4YdF42lPhMz6Kc/zdzKZpN9\r\njrshiIDhAD5NCno6dwqafBAW9WZl0sn7EnlLhD4Lwm8E9bRHnC9H82yFuqmNrzww\r\nzxBCQogJISwHiVz4EkU48B283ecBn0wT/fAa19cCgYEApKWsnEHgrhy1IxOpCoRh\r\nUhqdv2k1xDPN/8DUjtnAFtwmVcLa/zJopU/Zn4y1ZzSzjwECSTi+iWZRQ/YXXHPf\r\nl92SFjhFW92Niuy8w8FnevXjF6T7PYiy1SkJ9OR1QlZrXc04iiGBDazLu115A7ce\r\nanACS03OLw+CKgl6Q/RR83ECgYBCUngDVoimkMcIHHt3yJiP3ikeAKlRnMdJlsa0\r\nXWVZV4hCG3lDfRXsnEgWuimftNKf+6GdfYSvQdLdiQsCcjT5A4uLsQTByv5nf4uA\r\n1ZKOsFrmRrARzxGXhLDikvj7yP//7USkq+0BBGFhfuAvl7fMhPceyPZPehqB7/jf\r\nxX1LBQKBgAn5GgSXzzS0e06ZlP/VrKxreOHa5Z8wOmqqYQ0QTeczAbNNmuITdwwB\r\nNkbRqpVXRIfuj0BQBegAiix8om1W4it0cwz54IXBwQULxJR1StWxj3jo4QtpMQ+z\r\npVPdB1Ilb9zPV1YvDwRfdS1xsobzznAx56ecsXduZjs9mF61db8Q\r\n-----END RSA PRIVATE KEY-----\r\n",
+    "publicKey": "-----BEGIN PUBLIC KEY-----\r\nMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAj13sSYE40lAX2qpBvfdG\r\nfcSVNtBf8i5FH+E8FAhORwwPu+2S3yBQbgwHq30WWxunGb1NmZL1wkVZ+vf12Dtx\r\nqFRnMA08LfO4oO6oC4V8XfKeuHyJ1qlaKRINz6r9yDkTHtwWoBnlAINurlcNKgGD\r\n5p7D+G26Chbr/Oo0ZwHula9DxXy6eH8/bJ5/BynyNyyWRPoAO+UkUdY5utkFCUq2\r\ndbBIhovMgjjikf5p2oWqnRKXc+JKBegr6lSHkkhyqNhTmd8+wA+8Cace4sy1ajY1\r\nt5V4wfRZea5vwl/HlyyKodvHdxngJgg6H61JMYPkplY6Gr9OryBKEAgq02zYoYTD\r\nfwIDAQAB\r\n-----END PUBLIC KEY-----\r\n",
+    "accessKey": "QXP3VDG3SALNBX2QBJ1C",
+    "secretKey": "K5FyqZo5uFKfw9QBtn95o6vuPuD0zH/1seIrqPKqGnz8AxALNSx6EeRq7G1I6JJpS1XN13EhnwGn2ipsml3Uf2fQ00YgEmImG8wzGVZm8fWotpVO4ilN4JGyQCah81rNX4wZ9xHqDD7qYR5MyIERxR/osoXfctOwY7GGUjRKJfLOguNUlpaovejg6mZfTvYAiDF+PTO1sKUYqHt1IfKQtsK3dov1EFMBB5pWM7sVfncq/CthKN5M+VHx9Y87qdoP3+7AW+RCBbSDOfQgxvqtS7PIAf10mDl8k2kEURLz+RqChu4O4S0UzbEmtja7wa7WYhYKv/tM/QeW7kyNJMmnPg==",
+    "decryptedSecretKey": "n7PSZ3U6SgerF9PCNhXYsq3S3fRKVGdZTicGV8Ur"
+}

lib/executables/pensieveCreds/tests/unit/utilsSpec.js

@@ -0,0 +1,39 @@
+const assert = require('assert');
+const { parseServiceCredentials, decryptSecret } =
+    require('../../utils');
+const { privateKey, accessKey, secretKey, decryptedSecretKey }
+    = require('../resources.json');
+
+describe('decyrptSecret', () => {
+    it('should decrypt a secret', () => {
+        const instanceCredentials = {
+            privateKey,
+        };
+        const result = decryptSecret(instanceCredentials, secretKey);
+        assert.strictEqual(result, decryptedSecretKey);
+    });
+});
+
+describe('parseServiceCredentials', () => {
+    const conf = {
+        users: [{ accessKey,
+            accountType: 'service-clueso',
+            secretKey,
+            userName: 'Search Service Account' }],
+    };
+    const auth = JSON.stringify({ privateKey });
+
+    it('should parse service credentials', () => {
+        const result = parseServiceCredentials(conf, auth, 'clueso');
+        const expectedResult = {
+            accessKey,
+            secretKey: decryptedSecretKey,
+        };
+        assert.deepStrictEqual(result, expectedResult);
+    });
+
+    it('should return undefined if no such service', () => {
+        const result = parseServiceCredentials(conf, auth, undefined);
+        assert.strictEqual(result, undefined);
+    });
+});

lib/executables/pensieveCreds/utils.js

@@ -0,0 +1,38 @@
+const forge = require('node-forge');
+
+function decryptSecret(instanceCredentials, secret) {
+    const privateKey = forge.pki.privateKeyFromPem(
+        instanceCredentials.privateKey);
+    const encryptedSecretKey = forge.util.decode64(secret);
+    return privateKey.decrypt(encryptedSecretKey, 'RSA-OAEP', {
+        md: forge.md.sha256.create(),
+    });
+}
+
+function loadOverlayVersion(db, version, cb) {
+    db.get(`configuration/overlay/${version}`, {}, (err, val) => {
+        if (err) {
+            return cb(err);
+        }
+        return cb(null, JSON.parse(val));
+    });
+}
+
+function parseServiceCredentials(conf, auth, serviceName) {
+    const instanceAuth = JSON.parse(auth);
+    const serviceAccount = (conf.users || []).find(
+        u => u.accountType === `service-${serviceName}`);
+    if (!serviceAccount) {
+        return undefined;
+    }
+    return {
+        accessKey: serviceAccount.accessKey,
+        secretKey: decryptSecret(instanceAuth, serviceAccount.secretKey),
+    };
+}
+
+module.exports = {
+    decryptSecret,
+    loadOverlayVersion,
+    parseServiceCredentials,
+};