Merge branch 'bugfix/S3C-2987-serialStreamHelper' into bugfix/S3C-2987-featureBranch

The v0v1 migration step (keys are both in v0 and v1 format) and v1mig
(keys in v0 are being deleted) both use the same logic than the plain
v1 vformat, because all v1 keys exist hence the listing can benefit
from the v1 enhancements in those migration steps.

index.js

@@ -28,6 +28,7 @@ module.exports = {
             LRUCache: require('./lib/algos/cache/LRUCache'),
         },
         stream: {
+            SerialStream: require('./lib/algos/stream/SerialStream'),
             MergeStream: require('./lib/algos/stream/MergeStream'),
         },
     },

lib/algos/list/MPU.js

@@ -1,6 +1,6 @@
 'use strict'; // eslint-disable-line strict
 
-const { inc, checkLimit, listingParamsMasterKeysV0ToV1,
+const { inc, checkLimit, listingParamsMasterKeysV0ToV1, listingParamsV0ToV0Mig,
         FILTER_END, FILTER_ACCEPT } = require('./tools');
 const DEFAULT_MAX_KEYS = 1000;
 const VSConst = require('../../versioning/constants').VersioningConstants;
@@ -44,6 +44,18 @@ class MultipartUploads {
                 genMDParams: this.genMDParamsV0,
                 getObjectKey: this.getObjectKeyV0,
             },
+            [BucketVersioningKeyFormat.v0mig]: {
+                genMDParams: this.genMDParamsV0Mig,
+                getObjectKey: this.getObjectKeyV0,
+            },
+            [BucketVersioningKeyFormat.v0v1]: {
+                genMDParams: this.genMDParamsV1,
+                getObjectKey: this.getObjectKeyV1,
+            },
+            [BucketVersioningKeyFormat.v1mig]: {
+                genMDParams: this.genMDParamsV1,
+                getObjectKey: this.getObjectKeyV1,
+            },
             [BucketVersioningKeyFormat.v1]: {
                 genMDParams: this.genMDParamsV1,
                 getObjectKey: this.getObjectKeyV1,
@@ -73,6 +85,11 @@ class MultipartUploads {
         return params;
     }
 
+    genMDParamsV0Mig() {
+        const v0params = this.genMDParamsV0();
+        return listingParamsV0ToV0Mig(v0params);
+    }
+
     genMDParamsV1() {
         const v0params = this.genMDParamsV0();
         return listingParamsMasterKeysV0ToV1(v0params);

lib/algos/list/delimiter.js

@@ -1,7 +1,7 @@
 'use strict'; // eslint-disable-line strict
 
 const Extension = require('./Extension').default;
-const { inc, listingParamsMasterKeysV0ToV1,
+const { inc, listingParamsMasterKeysV0ToV1, listingParamsV0ToV0Mig,
         FILTER_END, FILTER_ACCEPT, FILTER_SKIP } = require('./tools');
 const VSConst = require('../../versioning/constants').VersioningConstants;
 const { DbPrefixes, BucketVersioningKeyFormat } = VSConst;
@@ -99,6 +99,21 @@ class Delimiter extends Extension {
                 getObjectKey: this.getObjectKeyV0,
                 skipping: this.skippingV0,
             },
+            [BucketVersioningKeyFormat.v0mig]: {
+                genMDParams: this.genMDParamsV0Mig,
+                getObjectKey: this.getObjectKeyV0,
+                skipping: this.skippingV0,
+            },
+            [BucketVersioningKeyFormat.v0v1]: {
+                genMDParams: this.genMDParamsV1,
+                getObjectKey: this.getObjectKeyV1,
+                skipping: this.skippingV1,
+            },
+            [BucketVersioningKeyFormat.v1mig]: {
+                genMDParams: this.genMDParamsV1,
+                getObjectKey: this.getObjectKeyV1,
+                skipping: this.skippingV1,
+            },
             [BucketVersioningKeyFormat.v1]: {
                 genMDParams: this.genMDParamsV1,
                 getObjectKey: this.getObjectKeyV1,
@@ -124,6 +139,11 @@ class Delimiter extends Extension {
         return params;
     }
 
+    genMDParamsV0Mig() {
+        const v0params = this.genMDParamsV0();
+        return listingParamsV0ToV0Mig(v0params);
+    }
+
     genMDParamsV1() {
         const params = this.genMDParamsV0();
         return listingParamsMasterKeysV0ToV1(params);

lib/algos/list/delimiterMaster.js

@@ -38,6 +38,18 @@ class DelimiterMaster extends Delimiter {
                 filter: this.filterV0,
                 skipping: this.skippingV0,
             },
+            [BucketVersioningKeyFormat.v0mig]: {
+                filter: this.filterV0,
+                skipping: this.skippingV0,
+            },
+            [BucketVersioningKeyFormat.v0v1]: {
+                filter: this.filterV1,
+                skipping: this.skippingV1,
+            },
+            [BucketVersioningKeyFormat.v1mig]: {
+                filter: this.filterV1,
+                skipping: this.skippingV1,
+            },
             [BucketVersioningKeyFormat.v1]: {
                 filter: this.filterV1,
                 skipping: this.skippingV1,

lib/algos/list/delimiterVersions.js

@@ -3,8 +3,8 @@
 const Delimiter = require('./delimiter').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 { inc, listingParamsV0ToV0Mig,
+        FILTER_END, FILTER_ACCEPT, FILTER_SKIP, SKIP_NONE } = require('./tools');
 
 const VID_SEP = VSConst.VersionId.Separator;
 const { DbPrefixes, BucketVersioningKeyFormat } = VSConst;
@@ -40,6 +40,21 @@ class DelimiterVersions extends Delimiter {
                 filter: this.filterV0,
                 skipping: this.skippingV0,
             },
+            [BucketVersioningKeyFormat.v0mig]: {
+                genMDParams: this.genMDParamsV0Mig,
+                filter: this.filterV0,
+                skipping: this.skippingV0,
+            },
+            [BucketVersioningKeyFormat.v0v1]: {
+                genMDParams: this.genMDParamsV1,
+                filter: this.filterV1,
+                skipping: this.skippingV1,
+            },
+            [BucketVersioningKeyFormat.v1mig]: {
+                genMDParams: this.genMDParamsV1,
+                filter: this.filterV1,
+                skipping: this.skippingV1,
+            },
             [BucketVersioningKeyFormat.v1]: {
                 genMDParams: this.genMDParamsV1,
                 filter: this.filterV1,
@@ -72,6 +87,11 @@ class DelimiterVersions extends Delimiter {
         return params;
     }
 
+    genMDParamsV0Mig() {
+        const v0params = this.genMDParamsV0();
+        return listingParamsV0ToV0Mig(v0params);
+    }
+
     genMDParamsV1() {
         // return an array of two listing params sets to ask for
         // synchronized listing of M and V ranges

lib/algos/list/tools.js

@@ -59,10 +59,59 @@ function listingParamsMasterKeysV0ToV1(v0params) {
     return v1params;
 }
 
+function listingParamsV0ToV0Mig(v0params) {
+    if ((v0params.gt !== undefined && v0params.gt >= inc(DbPrefixes.V1))
+        || (v0params.gte !== undefined && v0params.gte >= inc(DbPrefixes.V1))
+        || (v0params.lt !== undefined && v0params.lt <= DbPrefixes.V1)) {
+        return v0params;
+    }
+    if ((v0params.gt !== undefined && v0params.gt >= DbPrefixes.V1)
+        || (v0params.gte !== undefined && v0params.gte >= DbPrefixes.V1)) {
+        const v0migParams = Object.assign({}, v0params);
+        let greaterParam;
+        if (v0params.gt !== undefined) {
+            v0migParams.gt = inc(DbPrefixes.V1);
+            greaterParam = v0migParams.gt;
+        }
+        if (v0params.gte !== undefined) {
+            v0migParams.gte = inc(DbPrefixes.V1);
+            greaterParam = v0migParams.gte;
+        }
+        if (v0params.lt !== undefined && greaterParam !== undefined
+            && v0params.lt <= greaterParam) {
+            // we annihilated the valid range during our v0mig
+            // transform to skip V1 prefix: return an empty range with
+            // a trick instead of an invalid combo
+            return { lt: '' };
+        }
+        return v0migParams;
+    }
+    const rangeParams1 = {
+        lt: DbPrefixes.V1,
+    };
+    if (v0params.gt !== undefined) {
+        rangeParams1.gt = v0params.gt;
+    }
+    if (v0params.gte !== undefined) {
+        rangeParams1.gte = v0params.gte;
+    }
+    const rangeParams2 = {
+        gte: inc(DbPrefixes.V1),
+        // tell RepdServer._listObject() that the second listing is to
+        // be done after the first, not in parallel
+        serial: true,
+    };
+    if (v0params.lt !== undefined) {
+        rangeParams2.lt = v0params.lt;
+    }
+    return [rangeParams1, rangeParams2];
+}
+
 module.exports = {
     checkLimit,
     inc,
     listingParamsMasterKeysV0ToV1,
+    listingParamsV0ToV0Mig,
     SKIP_NONE,
     FILTER_END,
     FILTER_SKIP,

lib/algos/stream/SerialStream.js

@@ -0,0 +1,56 @@
+const stream = require('stream');
+
+class SerialStream extends stream.Readable {
+    constructor(stream1, stream2) {
+        super({ objectMode: true });
+
+        this._streams = [stream1, stream2];
+        this._currentStream = stream1;
+        this._streamToResume = null;
+
+        stream1.on('data', item => this._onItem(stream1, item));
+        stream1.once('end', () => this._onEndStream1());
+        stream1.once('error', err => this._onError(stream1, err));
+    }
+
+    _read() {
+        if (this._streamToResume) {
+            this._streamToResume.resume();
+            this._streamToResume = null;
+        }
+    }
+
+    _destroy(err, callback) {
+        this._currentStream.destroy();
+        if (this._currentStream === this._streams[0]) {
+            this._streams[1].destroy();
+        }
+        callback();
+    }
+
+    _onItem(myStream, item) {
+        if (!this.push(item)) {
+            myStream.pause();
+            this._streamToResume = myStream;
+        }
+    }
+
+    _onEndStream1() {
+        // stream1 is done, now move on with data from stream2
+        const stream2 = this._streams[1];
+        stream2.on('data', item => this._onItem(stream2, item));
+        stream2.once('end', () => this._onEnd());
+        stream2.once('error', err => this._onError(stream2, err));
+    }
+
+    _onEnd() {
+        this.push(null);
+    }
+
+    _onError(myStream, err) {
+        this.emit('error', err);
+        this._destroy(err, () => {});
+    }
+}
+
+module.exports = SerialStream;

lib/versioning/constants.js

@@ -3,6 +3,7 @@ module.exports.VersioningConstants = {
         Separator: '\0',
     },
     DbPrefixes: {
+        V1: '\x7f',
         Master: '\x7fM',
         Version: '\x7fV',
     },

tests/unit/algos/list/MPU.js

@@ -1,14 +1,28 @@
 'use strict'; // eslint-disable-line strict
 
 const assert = require('assert');
-const MultipartUploads =
-    require('../../../../lib/algos/list/MPU').MultipartUploads;
+const MultipartUploads = require('../../../../lib/algos/list/MPU').MultipartUploads;
+const { inc } = require('../../../../lib/algos/list/tools');
 const werelogs = require('werelogs').Logger;
 // eslint-disable-next-line new-cap
 const logger = new werelogs('listMpuTest');
 const performListing = require('../../../utils/performListing');
 const VSConst = require('../../../../lib/versioning/constants').VersioningConstants;
-const { DbPrefixes } = VSConst;
+const { DbPrefixes, BucketVersioningKeyFormat } = VSConst;
+
+function getListingKey(key, vFormat) {
+    if ([BucketVersioningKeyFormat.v0,
+         BucketVersioningKeyFormat.v0mig].includes(vFormat)) {
+        return key;
+    }
+    if ([BucketVersioningKeyFormat.v0v1,
+         BucketVersioningKeyFormat.v1mig,
+         BucketVersioningKeyFormat.v1].includes(vFormat)) {
+        return `${DbPrefixes.Master}${key}`;
+    }
+    assert.fail(`bad vFormat ${vFormat}`);
+    return undefined;
+}
 
 describe('Multipart Uploads listing algorithm', () => {
     const splitter = '**';
@@ -16,22 +30,14 @@ describe('Multipart Uploads listing algorithm', () => {
     const storageClass = 'STANDARD';
     const initiator1 = { ID: '1', DisplayName: 'initiator1' };
     const initiator2 = { ID: '2', DisplayName: 'initiator2' };
-    const keys = {
-        v0: [`${overviewPrefix}test/1${splitter}uploadId1`,
-             `${overviewPrefix}test/2${splitter}uploadId2`,
-             `${overviewPrefix}test/3${splitter}uploadId3`,
-             `${overviewPrefix}testMore/4${splitter}uploadId4`,
-             `${overviewPrefix}testMore/5${splitter}uploadId5`,
-             `${overviewPrefix}prefixTest/5${splitter}uploadId5`,
-            ],
-        v1: [`${DbPrefixes.Master}${overviewPrefix}test/1${splitter}uploadId1`,
-             `${DbPrefixes.Master}${overviewPrefix}test/2${splitter}uploadId2`,
-             `${DbPrefixes.Master}${overviewPrefix}test/3${splitter}uploadId3`,
-             `${DbPrefixes.Master}${overviewPrefix}testMore/4${splitter}uploadId4`,
-             `${DbPrefixes.Master}${overviewPrefix}testMore/5${splitter}uploadId5`,
-             `${DbPrefixes.Master}${overviewPrefix}prefixTest/5${splitter}uploadId5`,
-            ],
-    };
+    const v0keys = [
+        `${overviewPrefix}test/1${splitter}uploadId1`,
+        `${overviewPrefix}test/2${splitter}uploadId2`,
+        `${overviewPrefix}test/3${splitter}uploadId3`,
+        `${overviewPrefix}testMore/4${splitter}uploadId4`,
+        `${overviewPrefix}testMore/5${splitter}uploadId5`,
+        `${overviewPrefix}prefixTest/5${splitter}uploadId5`,
+    ];
     const values = [
         JSON.stringify({
             'key': 'test/1',
@@ -128,9 +134,15 @@ describe('Multipart Uploads listing algorithm', () => {
         done();
     });
 
-    ['v0', 'v1'].forEach(vFormat => {
-        const dbListing = keys[vFormat].map((key, i) => ({
-            key,
+    [
+        BucketVersioningKeyFormat.v0,
+        BucketVersioningKeyFormat.v0mig,
+        BucketVersioningKeyFormat.v0v1,
+        BucketVersioningKeyFormat.v1mig,
+        BucketVersioningKeyFormat.v1,
+    ].forEach(vFormat => {
+        const dbListing = v0keys.map((key, i) => ({
+            key: getListingKey(key, vFormat),
             value: values[i],
         }));
         it(`should perform a vFormat=${vFormat} listing of all keys`, () => {
@@ -171,4 +183,90 @@ describe('Multipart Uploads listing algorithm', () => {
             assert.deepStrictEqual(listingResult, expectedResult);
         });
     });
+
+    describe('MultipartUploads.genMDParams()', () => {
+        [{
+            listingParams: {
+                splitter,
+            },
+            mdParams: {
+                [BucketVersioningKeyFormat.v0]: {},
+                [BucketVersioningKeyFormat.v0mig]: [{
+                    lt: DbPrefixes.V1,
+                }, {
+                    gte: inc(DbPrefixes.V1),
+                    serial: true,
+                }],
+                [BucketVersioningKeyFormat.v1]: {
+                    gte: DbPrefixes.Master,
+                    lt: inc(DbPrefixes.Master),
+                },
+            },
+        }, {
+            listingParams: {
+                splitter,
+                prefix: 'foo/bar',
+            },
+            mdParams: {
+                [BucketVersioningKeyFormat.v0]: {
+                    gte: 'foo/bar',
+                    lt: 'foo/bas',
+                },
+                [BucketVersioningKeyFormat.v0mig]: {
+                    gte: 'foo/bar',
+                    lt: 'foo/bas',
+                },
+                [BucketVersioningKeyFormat.v1]: {
+                    gte: `${DbPrefixes.Master}foo/bar`,
+                    lt: `${DbPrefixes.Master}foo/bas`,
+                },
+            },
+        }, {
+            listingParams: {
+                splitter,
+                keyMarker: 'marker',
+            },
+            mdParams: {
+                [BucketVersioningKeyFormat.v0]: {
+                    gt: `${overviewPrefix}marker${inc(splitter)}`,
+                },
+                [BucketVersioningKeyFormat.v0mig]: [{
+                    gt: `${overviewPrefix}marker${inc(splitter)}`,
+                    lt: DbPrefixes.V1,
+                }, {
+                    gte: inc(DbPrefixes.V1),
+                    serial: true,
+                }],
+                [BucketVersioningKeyFormat.v1]: {
+                    gt: `${DbPrefixes.Master}${overviewPrefix}marker${inc(splitter)}`,
+                    lt: inc(DbPrefixes.Master),
+                },
+            },
+        }].forEach(testCase => {
+            [
+                BucketVersioningKeyFormat.v0,
+                BucketVersioningKeyFormat.v0mig,
+                BucketVersioningKeyFormat.v0v1,
+                BucketVersioningKeyFormat.v1mig,
+                BucketVersioningKeyFormat.v1,
+            ].forEach(vFormat => {
+                it(`with vFormat=${vFormat}, listing params ${JSON.stringify(testCase.listingParams)}`, () => {
+                    const delimiter = new MultipartUploads(
+                        testCase.listingParams, logger, vFormat);
+                    const mdParams = delimiter.genMDParams();
+                    let paramsVFormat;
+                    if ([BucketVersioningKeyFormat.v0v1,
+                         BucketVersioningKeyFormat.v1mig,
+                         BucketVersioningKeyFormat.v1].includes(vFormat)) {
+                        // all above vformats are equivalent to v1 when it
+                        // comes to generating md params
+                        paramsVFormat = BucketVersioningKeyFormat.v1;
+                    } else {
+                        paramsVFormat = vFormat;
+                    }
+                    assert.deepStrictEqual(mdParams, testCase.mdParams[paramsVFormat]);
+                });
+            });
+        });
+    });
 });

tests/unit/algos/list/delimiter.js

@@ -11,7 +11,7 @@ const performListing = require('../../../utils/performListing');
 const zpad = require('../../helpers').zpad;
 const { inc } = require('../../../../lib/algos/list/tools');
 const VSConst = require('../../../../lib/versioning/constants').VersioningConstants;
-const { DbPrefixes } = VSConst;
+const { DbPrefixes, BucketVersioningKeyFormat } = VSConst;
 
 class Test {
     constructor(name, input, genMDParams, output, filter) {
@@ -90,8 +90,14 @@ const receivedNonAlphaData = nonAlphabeticalData.map(
 
 const tests = [
     new Test('all elements', {}, {
-        v0: {},
-        v1: {
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         },
@@ -105,10 +111,17 @@ const tests = [
     new Test('with valid marker', {
         marker: receivedData[4].key,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: receivedData[4].key,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: [{
+            gt: receivedData[4].key,
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}${receivedData[4].key}`,
             lt: inc(DbPrefixes.Master),
         },
@@ -129,10 +142,17 @@ const tests = [
         marker: 'zzzz',
         delimiter: '/',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'zzzz',
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: [{
+            gt: 'zzzz',
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}zzzz`,
             lt: inc(DbPrefixes.Master),
         },
@@ -146,8 +166,14 @@ const tests = [
     new Test('with makKeys', {
         maxKeys: 3,
     }, {
-        v0: {},
-        v1: {
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         },
@@ -161,8 +187,14 @@ const tests = [
     new Test('with big makKeys', {
         maxKeys: 15000,
     }, {
-        v0: {},
-        v1: {
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         },
@@ -176,8 +208,14 @@ const tests = [
     new Test('with delimiter', {
         delimiter: '/',
     }, {
-        v0: {},
-        v1: {
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         },
@@ -193,8 +231,14 @@ const tests = [
     new Test('with long delimiter', {
         delimiter: 'notes/summer',
     }, {
-        v0: {},
-        v1: {
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         },
@@ -218,11 +262,15 @@ const tests = [
         prefix: 'notes/summer/',
         marker: 'notes/summer0',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `notes/summer${inc('/')}`,
             lt: `notes/summer${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: `notes/summer${inc('/')}`,
+            lt: `notes/summer${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/summer${inc('/')}`,
             lt: `${DbPrefixes.Master}notes/summer${inc('/')}`,
         },
@@ -237,11 +285,15 @@ const tests = [
         delimiter: '/',
         prefix: 'notes/',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gte: 'notes/',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gte: 'notes/',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gte: `${DbPrefixes.Master}notes/`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -264,11 +316,15 @@ const tests = [
         prefix: 'notes/',
         marker: 'notes/year.txt',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/year.txt',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/year.txt',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/year.txt`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -289,11 +345,15 @@ const tests = [
         marker: 'notes/',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -311,11 +371,15 @@ const tests = [
         marker: 'notes/spring/',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/spring/',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/spring/',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/spring/`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -333,11 +397,15 @@ const tests = [
         marker: 'notes/summer/',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/summer/',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/summer/',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/summer/`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -357,11 +425,15 @@ const tests = [
         marker: 'notes/year.txt',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/year.txt',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/year.txt',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/year.txt`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -381,11 +453,15 @@ const tests = [
         marker: 'notes/yore.rs',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/yore.rs',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/yore.rs',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/yore.rs`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -400,8 +476,14 @@ const tests = [
     new Test('all elements v2', {
         v2: true,
     }, {
-        v0: {},
-        v1: {
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         },
@@ -416,10 +498,17 @@ const tests = [
         startAfter: receivedData[4].key,
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: receivedData[4].key,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: [{
+            gt: receivedData[4].key,
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}${receivedData[4].key}`,
             lt: inc(DbPrefixes.Master),
         },
@@ -441,10 +530,17 @@ const tests = [
         delimiter: '/',
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'zzzz',
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: [{
+            gt: 'zzzz',
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}zzzz`,
             lt: inc(DbPrefixes.Master),
         },
@@ -459,10 +555,17 @@ const tests = [
         continuationToken: receivedData[4].key,
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: receivedData[4].key,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: [{
+            gt: receivedData[4].key,
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}${receivedData[4].key}`,
             lt: inc(DbPrefixes.Master),
         },
@@ -484,10 +587,17 @@ const tests = [
         delimiter: '/',
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'zzzz',
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: [{
+            gt: 'zzzz',
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}zzzz`,
             lt: inc(DbPrefixes.Master),
         },
@@ -503,11 +613,15 @@ const tests = [
         prefix: 'notes/summer/',
         startAfter: 'notes/summer0',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gte: 'notes/summer/',
             lt: `notes/summer${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gte: 'notes/summer/',
+            lt: `notes/summer${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gte: `${DbPrefixes.Master}notes/summer/`,
             lt: `${DbPrefixes.Master}notes/summer${inc('/')}`,
         },
@@ -523,11 +637,15 @@ const tests = [
         prefix: 'notes/summer/',
         continuationToken: 'notes/summer0',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gte: 'notes/summer/',
             lt: `notes/summer${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gte: 'notes/summer/',
+            lt: `notes/summer${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gte: `${DbPrefixes.Master}notes/summer/`,
             lt: `${DbPrefixes.Master}notes/summer${inc('/')}`,
         },
@@ -544,10 +662,17 @@ const tests = [
         maxKeys: 1,
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/year.txt',
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: [{
+            gt: 'notes/year.txt',
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/year.txt`,
             lt: inc(DbPrefixes.Master),
         },
@@ -568,11 +693,15 @@ const tests = [
         maxKeys: 1,
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -591,11 +720,15 @@ const tests = [
         maxKeys: 1,
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/spring/',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/spring/',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/spring/`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -614,11 +747,15 @@ const tests = [
         maxKeys: 1,
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/summer/',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/summer/',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/summer/`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -639,11 +776,15 @@ const tests = [
         maxKeys: 1,
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/year.txt',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/year.txt',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/year.txt`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -664,11 +805,15 @@ const tests = [
         maxKeys: 1,
         v2: true,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: 'notes/yore.rs',
             lt: `notes${inc('/')}`,
         },
-        v1: {
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'notes/yore.rs',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: {
             gt: `${DbPrefixes.Master}notes/yore.rs`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         },
@@ -680,6 +825,109 @@ const tests = [
         NextContinuationToken: undefined,
     }, (e, input) => e.key > input.startAfter),
 
+    new Test('with startAfter after vformat V1 prefix', {
+        delimiter: '/',
+        startAfter: 'éléphant pâle',
+        maxKeys: 3,
+        v2: true,
+    }, {
+        [BucketVersioningKeyFormat.v0]: {
+            gt: 'éléphant pâle',
+        },
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: 'éléphant pâle',
+        },
+        [BucketVersioningKeyFormat.v1]: {
+            gt: `${DbPrefixes.Master}éléphant pâle`,
+            lt: inc(DbPrefixes.Master),
+        },
+    }, {
+        Contents: [],
+        CommonPrefixes: [],
+        Delimiter: '/',
+        IsTruncated: false,
+        NextContinuationToken: undefined,
+    }, (e, input) => e.key > input.startAfter),
+
+    new Test('with startAfter inside vformat V1 prefix', {
+        delimiter: '/',
+        startAfter: `${DbPrefixes.V1}foo`,
+        maxKeys: 3,
+        v2: true,
+    }, {
+        [BucketVersioningKeyFormat.v0]: {
+            gt: `${DbPrefixes.V1}foo`,
+        },
+        // v0mig skips all V1-prefixed keys to start at the beginning
+        // of the second v0 range (to skip V1 keys being migrated)
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: inc(DbPrefixes.V1),
+        },
+        [BucketVersioningKeyFormat.v1]: {
+            gt: `${DbPrefixes.Master}${DbPrefixes.V1}foo`,
+            lt: inc(DbPrefixes.Master),
+        },
+    }, {
+        Contents: [],
+        CommonPrefixes: [],
+        Delimiter: '/',
+        IsTruncated: false,
+        NextContinuationToken: undefined,
+    }, (e, input) => e.key > input.startAfter),
+
+    new Test('with prefix after vformat V1 prefix', {
+        delimiter: '/',
+        prefix: 'éléphant pâle/',
+        maxKeys: 3,
+        v2: true,
+    }, {
+        [BucketVersioningKeyFormat.v0]: {
+            gte: 'éléphant pâle/',
+            lt: 'éléphant pâle0',
+        },
+        [BucketVersioningKeyFormat.v0mig]: {
+            gte: 'éléphant pâle/',
+            lt: 'éléphant pâle0',
+        },
+        [BucketVersioningKeyFormat.v1]: {
+            gte: `${DbPrefixes.Master}éléphant pâle/`,
+            lt: `${DbPrefixes.Master}éléphant pâle0`,
+        },
+    }, {
+        Contents: [],
+        CommonPrefixes: [],
+        Delimiter: '/',
+        IsTruncated: false,
+        NextContinuationToken: undefined,
+    }, (e, input) => e.key > input.startAfter),
+
+    new Test('with prefix inside vformat V1 prefix', {
+        delimiter: '/',
+        prefix: `${DbPrefixes.V1}foo/`,
+        maxKeys: 3,
+        v2: true,
+    }, {
+        [BucketVersioningKeyFormat.v0]: {
+            gte: `${DbPrefixes.V1}foo/`,
+            lt: `${DbPrefixes.V1}foo0`,
+        },
+        // v0mig skips the V1 prefix altogether to avoid returning V1
+        // keys being migrated. It uses a trick: passing "lt: ''"
+        // (empty string) forces to list an empty range
+        [BucketVersioningKeyFormat.v0mig]: {
+            lt: '',
+        },
+        [BucketVersioningKeyFormat.v1]: {
+            gte: `${DbPrefixes.Master}${DbPrefixes.V1}foo/`,
+            lt: `${DbPrefixes.Master}${DbPrefixes.V1}foo0`,
+        },
+    }, {
+        Contents: [],
+        CommonPrefixes: [],
+        Delimiter: '/',
+        IsTruncated: false,
+        NextContinuationToken: undefined,
+    }, (e, input) => e.key > input.startAfter),
 ];
 
 const alphabeticalOrderTests = [
@@ -708,10 +956,13 @@ function getTestListing(test, data, vFormat) {
     return data
         .filter(e => test.filter(e, test.input))
         .map(obj => {
-            if (vFormat === 'v0') {
+            if ([BucketVersioningKeyFormat.v0,
+                 BucketVersioningKeyFormat.v0mig].includes(vFormat)) {
                 return obj;
             }
-            if (vFormat === 'v1') {
+            if ([BucketVersioningKeyFormat.v0v1,
+                 BucketVersioningKeyFormat.v1mig,
+                 BucketVersioningKeyFormat.v1].includes(vFormat)) {
                 return {
                     key: `${DbPrefixes.Master}${obj.key}`,
                     value: obj.value,
@@ -721,18 +972,39 @@ function getTestListing(test, data, vFormat) {
         });
 }
 
-['v0', 'v1'].forEach(vFormat => {
+[
+    BucketVersioningKeyFormat.v0,
+    BucketVersioningKeyFormat.v0mig,
+    BucketVersioningKeyFormat.v0v1,
+    BucketVersioningKeyFormat.v1mig,
+    BucketVersioningKeyFormat.v1,
+].forEach(vFormat => {
     describe(`vFormat=${vFormat} Delimiter listing algorithm`, () => {
         it('Should return good skipping value for DelimiterMaster', () => {
             const delimiter = new DelimiterMaster({ delimiter: '/' });
             for (let i = 0; i < 100; i++) {
+                let key;
+                if ([BucketVersioningKeyFormat.v0v1,
+                     BucketVersioningKeyFormat.v1mig,
+                     BucketVersioningKeyFormat.v1].includes(vFormat)) {
+                    key = `${DbPrefixes.Master}foo/${zpad(i)}`;
+                } else {
+                    key = `foo/${zpad(i)}`;
+                }
                 delimiter.filter({
-                    key: `${vFormat === 'v1' ? DbPrefixes.Master : ''}foo/${zpad(i)}`,
+                    key,
                     value: '{}',
                 });
             }
-            assert.strictEqual(delimiter.skipping(),
-                               `${vFormat === 'v1' ? DbPrefixes.Master : ''}foo/`);
+            let skipping;
+            if ([BucketVersioningKeyFormat.v0v1,
+                 BucketVersioningKeyFormat.v1mig,
+                 BucketVersioningKeyFormat.v1].includes(vFormat)) {
+                skipping = `${DbPrefixes.Master}foo/`;
+            } else {
+                skipping = 'foo/';
+            }
+            assert.strictEqual(delimiter.skipping(), skipping);
         });
 
         it('Should set Delimiter alphabeticalOrder field to the expected value', () => {
@@ -748,7 +1020,17 @@ function getTestListing(test, data, vFormat) {
             it(`Should return metadata listing params to list ${test.name}`, () => {
                 const listing = new Delimiter(test.input, logger, vFormat);
                 const params = listing.genMDParams();
-                assert.deepStrictEqual(params, test.genMDParams[vFormat]);
+                let paramsVFormat;
+                if ([BucketVersioningKeyFormat.v0v1,
+                     BucketVersioningKeyFormat.v1mig,
+                     BucketVersioningKeyFormat.v1].includes(vFormat)) {
+                    // all above vformats are equivalent to v1 when it
+                    // comes to generating md params
+                    paramsVFormat = BucketVersioningKeyFormat.v1;
+                } else {
+                    paramsVFormat = vFormat;
+                }
+                assert.deepStrictEqual(params, test.genMDParams[paramsVFormat]);
             });
             it(`Should list ${test.name}`, () => {
                 // Simulate skip scan done by LevelDB
@@ -759,7 +1041,7 @@ function getTestListing(test, data, vFormat) {
         });
 
         // Only v0 gets a listing of master and version keys together.
-        if (vFormat === 'v0') {
+        if (vFormat === BucketVersioningKeyFormat.v0) {
             tests.forEach(test => {
                 it(`Should list master versions ${test.name}`, () => {
                     // Simulate skip scan done by LevelDB

tests/unit/algos/list/delimiterMaster.js

@@ -13,7 +13,7 @@ const VSConst =
     require('../../../../lib/versioning/constants').VersioningConstants;
 const Version = require('../../../../lib/versioning/Version').Version;
 const { generateVersionId } = require('../../../../lib/versioning/VersionID');
-const { DbPrefixes } = VSConst;
+const { DbPrefixes, BucketVersioningKeyFormat } = VSConst;
 
 
 const VID_SEP = VSConst.VersionId.Separator;
@@ -35,16 +35,25 @@ const fakeLogger = {
 };
 
 function getListingKey(key, vFormat) {
-    if (vFormat === 'v0') {
+    if ([BucketVersioningKeyFormat.v0,
+         BucketVersioningKeyFormat.v0mig].includes(vFormat)) {
         return key;
     }
-    if (vFormat === 'v1') {
+    if ([BucketVersioningKeyFormat.v0v1,
+         BucketVersioningKeyFormat.v1mig,
+         BucketVersioningKeyFormat.v1].includes(vFormat)) {
         return `${DbPrefixes.Master}${key}`;
     }
     return assert.fail(`bad vFormat ${vFormat}`);
 }
 
-['v0', 'v1'].forEach(vFormat => {
+[
+    BucketVersioningKeyFormat.v0,
+    BucketVersioningKeyFormat.v0mig,
+    BucketVersioningKeyFormat.v0v1,
+    BucketVersioningKeyFormat.v1mig,
+    BucketVersioningKeyFormat.v1,
+].forEach(vFormat => {
     describe(`Delimiter All masters listing algorithm vFormat=${vFormat}`, () => {
         it('should return SKIP_NONE for DelimiterMaster when both NextMarker ' +
         'and NextContinuationToken are undefined', () => {
@@ -102,7 +111,9 @@ function getListingKey(key, vFormat) {
             /* When a delimiter is set and the NextMarker ends with the
              * delimiter it should return the next marker value. */
             assert.strictEqual(delimiter.NextMarker, keyWithEndingDelimiter);
-            const skipKey = vFormat === 'v1' ?
+            const skipKey = [BucketVersioningKeyFormat.v0v1,
+                             BucketVersioningKeyFormat.v1mig,
+                             BucketVersioningKeyFormat.v1].includes(vFormat) ?
                   `${DbPrefixes.Master}${keyWithEndingDelimiter}` :
                   keyWithEndingDelimiter;
             assert.strictEqual(delimiter.skipping(), skipKey);
@@ -135,7 +146,8 @@ function getListingKey(key, vFormat) {
 
             const listingKey = getListingKey(key, vFormat);
             assert.strictEqual(delimiter.filter({ key: listingKey, value }), FILTER_ACCEPT);
-            if (vFormat === 'v0') {
+            if ([BucketVersioningKeyFormat.v0,
+                 BucketVersioningKeyFormat.v0mig].includes(vFormat)) {
                 assert.strictEqual(delimiter.prvKey, key);
             }
             assert.strictEqual(delimiter.NextMarker, key);
@@ -206,7 +218,8 @@ function getListingKey(key, vFormat) {
             });
         });
 
-        if (vFormat === 'v0') {
+        if ([BucketVersioningKeyFormat.v0,
+             BucketVersioningKeyFormat.v0mig].includes(vFormat)) {
             it('should accept a PHD version as first input', () => {
                 const delimiter = new DelimiterMaster({}, fakeLogger, vFormat);
                 const keyPHD = 'keyPHD';

tests/unit/algos/list/delimiterVersions.js

@@ -9,7 +9,7 @@ const performListing = require('../../../utils/performListing');
 const zpad = require('../../helpers').zpad;
 const { inc } = require('../../../../lib/algos/list/tools');
 const VSConst = require('../../../../lib/versioning/constants').VersioningConstants;
-const { DbPrefixes } = VSConst;
+const { DbPrefixes, BucketVersioningKeyFormat } = VSConst;
 const VID_SEP = VSConst.VersionId.Separator;
 
 class Test {
@@ -32,75 +32,42 @@ const bar = '{"versionId":"bar"}';
 const qux = '{"versionId":"qux"}';
 const valuePHD = '{"isPHD":"true","versionId":"1234567890abcdefg"}';
 const valueDeleteMarker = '{"hello":"world","isDeleteMarker":"true"}';
-const dataVersioned = {
-    v0: [
-        { key: 'Pâtisserie=中文-español-English', value: bar },
-        { key: `Pâtisserie=中文-español-English${VID_SEP}bar`, value: bar },
-        { key: `Pâtisserie=中文-español-English${VID_SEP}foo`, value: foo },
-        { key: 'notes/spring/1.txt', value: bar },
-        { key: `notes/spring/1.txt${VID_SEP}bar`, value: bar },
-        { key: `notes/spring/1.txt${VID_SEP}foo`, value: foo },
-        { key: `notes/spring/1.txt${VID_SEP}qux`, value: qux },
-        { key: 'notes/spring/2.txt', value: valuePHD },
-        { key: `notes/spring/2.txt${VID_SEP}bar`, value: valueDeleteMarker },
-        { key: `notes/spring/2.txt${VID_SEP}foo`, value: foo },
-        { key: 'notes/spring/march/1.txt',
-          value: '{"versionId":"null","isNull":true}' },
-        { key: `notes/spring/march/1.txt${VID_SEP}bar`, value: bar },
-        { key: `notes/spring/march/1.txt${VID_SEP}foo`, value: foo },
-        { key: 'notes/summer/1.txt', value: bar },
-        { key: `notes/summer/1.txt${VID_SEP}bar`, value: bar },
-        { key: `notes/summer/1.txt${VID_SEP}foo`, value: foo },
-        { key: 'notes/summer/2.txt', value: bar },
-        { key: `notes/summer/2.txt${VID_SEP}bar`, value: bar },
-        { key: 'notes/summer/4.txt', value: valuePHD },
-        { key: `notes/summer/4.txt${VID_SEP}bar`, value: valueDeleteMarker },
-        { key: `notes/summer/4.txt${VID_SEP}foo`, value: valueDeleteMarker },
-        { key: `notes/summer/4.txt${VID_SEP}qux`, value: valueDeleteMarker },
-        { key: 'notes/summer/44.txt', value: valuePHD },
-        { key: 'notes/summer/444.txt', value: valueDeleteMarker },
-        { key: 'notes/summer/4444.txt', value: valuePHD },
-        { key: 'notes/summer/44444.txt', value: valueDeleteMarker },
-        { key: 'notes/summer/444444.txt', value: valuePHD },
-        { key: 'notes/summer/august/1.txt', value },
-        { key: 'notes/year.txt', value },
-        { key: 'notes/yore.rs', value },
-        { key: 'notes/zaphod/Beeblebrox.txt', value },
-    ],
-    v1: [ // we add M and V prefixes in getTestListing() due to the
-          // test cases needing the original key to filter
-        { key: 'Pâtisserie=中文-español-English', value: bar },
-        { key: `Pâtisserie=中文-español-English${VID_SEP}bar`, value: bar },
-        { key: `Pâtisserie=中文-español-English${VID_SEP}foo`, value: foo },
-        { key: 'notes/spring/1.txt', value: bar },
-        { key: `notes/spring/1.txt${VID_SEP}bar`, value: bar },
-        { key: `notes/spring/1.txt${VID_SEP}foo`, value: foo },
-        { key: `notes/spring/1.txt${VID_SEP}qux`, value: qux },
-        { key: `notes/spring/2.txt${VID_SEP}bar`, value: valueDeleteMarker },
-        { key: `notes/spring/2.txt${VID_SEP}foo`, value: foo },
-        { key: 'notes/spring/march/1.txt',
-          value: '{"versionId":"null","isNull":true}' },
-        { key: `notes/spring/march/1.txt${VID_SEP}bar`, value: bar },
-        { key: `notes/spring/march/1.txt${VID_SEP}foo`, value: foo },
-        { key: 'notes/summer/1.txt', value: bar },
-        { key: `notes/summer/1.txt${VID_SEP}bar`, value: bar },
-        { key: `notes/summer/1.txt${VID_SEP}foo`, value: foo },
-        { key: 'notes/summer/2.txt', value: bar },
-        { key: `notes/summer/2.txt${VID_SEP}bar`, value: bar },
-        { key: `notes/summer/4.txt${VID_SEP}bar`, value: valueDeleteMarker },
-        { key: `notes/summer/4.txt${VID_SEP}foo`, value: valueDeleteMarker },
-        { key: `notes/summer/4.txt${VID_SEP}qux`, value: valueDeleteMarker },
-        // Compared to v0, the two following keys are version keys
-        // that we give a version ID, because delete markers do not
-        // have a master key in v1.
-        { key: `notes/summer/444.txt${VID_SEP}null`, value: valueDeleteMarker },
-        { key: `notes/summer/44444.txt${VID_SEP}null`, value: valueDeleteMarker },
-        { key: 'notes/summer/august/1.txt', value },
-        { key: 'notes/year.txt', value },
-        { key: 'notes/yore.rs', value },
-        { key: 'notes/zaphod/Beeblebrox.txt', value },
-    ],
-};
+
+const rawListingData = [
+    { key: 'Pâtisserie=中文-español-English', value: bar },
+    { key: `Pâtisserie=中文-español-English${VID_SEP}bar`, value: bar },
+    { key: `Pâtisserie=中文-español-English${VID_SEP}foo`, value: foo },
+    { key: 'notes/spring/1.txt', value: bar },
+    { key: `notes/spring/1.txt${VID_SEP}bar`, value: bar },
+    { key: `notes/spring/1.txt${VID_SEP}foo`, value: foo },
+    { key: `notes/spring/1.txt${VID_SEP}qux`, value: qux },
+    { key: 'notes/spring/2.txt', value: valuePHD },
+    { key: `notes/spring/2.txt${VID_SEP}bar`, value: valueDeleteMarker },
+    { key: `notes/spring/2.txt${VID_SEP}foo`, value: foo },
+    { key: 'notes/spring/march/1.txt',
+      value: '{"versionId":"null","isNull":true}' },
+    { key: `notes/spring/march/1.txt${VID_SEP}bar`, value: bar },
+    { key: `notes/spring/march/1.txt${VID_SEP}foo`, value: foo },
+    { key: 'notes/summer/1.txt', value: bar },
+    { key: `notes/summer/1.txt${VID_SEP}bar`, value: bar },
+    { key: `notes/summer/1.txt${VID_SEP}foo`, value: foo },
+    { key: 'notes/summer/2.txt', value: bar },
+    { key: `notes/summer/2.txt${VID_SEP}bar`, value: bar },
+    { key: 'notes/summer/4.txt', value: valuePHD },
+    { key: `notes/summer/4.txt${VID_SEP}bar`, value: valueDeleteMarker },
+    { key: `notes/summer/4.txt${VID_SEP}foo`, value: valueDeleteMarker },
+    { key: `notes/summer/4.txt${VID_SEP}qux`, value: valueDeleteMarker },
+    { key: 'notes/summer/44.txt', value: valuePHD },
+    { key: 'notes/summer/444.txt', value: valueDeleteMarker },
+    { key: 'notes/summer/4444.txt', value: valuePHD },
+    { key: 'notes/summer/44444.txt', value: valueDeleteMarker },
+    { key: 'notes/summer/444444.txt', value: valuePHD },
+    { key: 'notes/summer/august/1.txt', value },
+    { key: 'notes/year.txt', value },
+    { key: 'notes/yore.rs', value },
+    { key: 'notes/zaphod/Beeblebrox.txt', value },
+];
+
 const receivedData = [
     { key: 'Pâtisserie=中文-español-English', value: bar, versionId: 'bar' },
     { key: 'Pâtisserie=中文-español-English', value: foo, versionId: 'foo' },
@@ -130,9 +97,20 @@ const receivedData = [
 ];
 const tests = [
     new Test('all versions', {}, {
-        v0: {},
-        v1: [{ gte: DbPrefixes.Master, lt: inc(DbPrefixes.Master) },
-             { gte: DbPrefixes.Version, lt: inc(DbPrefixes.Version) }],
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: [{
+            gte: DbPrefixes.Master,
+            lt: inc(DbPrefixes.Master),
+        }, {
+            gte: DbPrefixes.Version,
+            lt: inc(DbPrefixes.Version),
+        }],
     }, {
         Versions: receivedData,
         CommonPrefixes: [],
@@ -144,10 +122,17 @@ const tests = [
     new Test('with valid key marker', {
         keyMarker: receivedData[3].key,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `${receivedData[3].key}\u0001`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: [{
+            gt: `${receivedData[3].key}\u0001`,
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: [{
             gt: `${DbPrefixes.Master}${receivedData[3].key}${inc(VID_SEP)}`,
             lt: inc(DbPrefixes.Master),
         }, {
@@ -166,10 +151,17 @@ const tests = [
         keyMarker: 'zzzz',
         delimiter: '/',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `zzzz${inc(VID_SEP)}`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: [{
+            gt: `zzzz${inc(VID_SEP)}`,
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: [{
             gt: `${DbPrefixes.Master}zzzz${inc(VID_SEP)}`,
             lt: inc(DbPrefixes.Master),
         }, {
@@ -187,8 +179,14 @@ const tests = [
     new Test('with maxKeys', {
         maxKeys: 3,
     }, {
-        v0: {},
-        v1: [{
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: [{
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         }, {
@@ -206,8 +204,14 @@ const tests = [
     new Test('with big maxKeys', {
         maxKeys: 15000,
     }, {
-        v0: {},
-        v1: [{
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: [{
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         }, {
@@ -225,8 +229,14 @@ const tests = [
     new Test('with delimiter', {
         delimiter: '/',
     }, {
-        v0: {},
-        v1: [{
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: [{
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         }, {
@@ -247,8 +257,14 @@ const tests = [
     new Test('with long delimiter', {
         delimiter: 'notes/summer',
     }, {
-        v0: {},
-        v1: [{
+        [BucketVersioningKeyFormat.v0]: {},
+        [BucketVersioningKeyFormat.v0mig]: [{
+            lt: DbPrefixes.V1,
+        }, {
+            gte: inc(DbPrefixes.V1),
+            serial: true,
+        }],
+        [BucketVersioningKeyFormat.v1]: [{
             gte: DbPrefixes.Master,
             lt: inc(DbPrefixes.Master),
         }, {
@@ -269,11 +285,15 @@ const tests = [
         prefix: 'notes/summer/',
         keyMarker: 'notes/summer0',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `notes/summer0${inc(VID_SEP)}`,
             lt: `notes/summer${inc('/')}`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: `notes/summer0${inc(VID_SEP)}`,
+            lt: `notes/summer${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: [{
             gt: `${DbPrefixes.Master}notes/summer0${inc(VID_SEP)}`,
             lt: `${DbPrefixes.Master}notes/summer${inc('/')}`,
         }, {
@@ -292,11 +312,15 @@ const tests = [
         delimiter: '/',
         prefix: 'notes/',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gte: 'notes/',
             lt: `notes${inc('/')}`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: {
+            gte: 'notes/',
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: [{
             gte: `${DbPrefixes.Master}notes/`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         }, {
@@ -323,11 +347,15 @@ const tests = [
         prefix: 'notes/',
         keyMarker: 'notes/year.txt',
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `notes/year.txt${inc(VID_SEP)}`,
             lt: `notes${inc('/')}`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: `notes/year.txt${inc(VID_SEP)}`,
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: [{
             gt: `${DbPrefixes.Master}notes/year.txt${inc(VID_SEP)}`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         }, {
@@ -352,11 +380,15 @@ const tests = [
         keyMarker: 'notes/',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `notes/${inc(VID_SEP)}`,
             lt: `notes${inc('/')}`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: `notes/${inc(VID_SEP)}`,
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: [{
             gt: `${DbPrefixes.Master}notes/${inc(VID_SEP)}`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         }, {
@@ -378,11 +410,15 @@ const tests = [
         keyMarker: 'notes/spring/',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `notes/spring/${inc(VID_SEP)}`,
             lt: `notes${inc('/')}`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: `notes/spring/${inc(VID_SEP)}`,
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: [{
             gt: `${DbPrefixes.Master}notes/spring/${inc(VID_SEP)}`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         }, {
@@ -404,11 +440,15 @@ const tests = [
         keyMarker: 'notes/summer/',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `notes/summer/${inc(VID_SEP)}`,
             lt: `notes${inc('/')}`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: `notes/summer/${inc(VID_SEP)}`,
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: [{
             gt: `${DbPrefixes.Master}notes/summer/${inc(VID_SEP)}`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         }, {
@@ -432,11 +472,15 @@ const tests = [
         keyMarker: 'notes/year.txt',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `notes/year.txt${inc(VID_SEP)}`,
             lt: `notes${inc('/')}`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: `notes/year.txt${inc(VID_SEP)}`,
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: [{
             gt: `${DbPrefixes.Master}notes/year.txt${inc(VID_SEP)}`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         }, {
@@ -460,11 +504,15 @@ const tests = [
         keyMarker: 'notes/yore.rs',
         maxKeys: 1,
     }, {
-        v0: {
+        [BucketVersioningKeyFormat.v0]: {
             gt: `notes/yore.rs${inc(VID_SEP)}`,
             lt: `notes${inc('/')}`,
         },
-        v1: [{
+        [BucketVersioningKeyFormat.v0mig]: {
+            gt: `notes/yore.rs${inc(VID_SEP)}`,
+            lt: `notes${inc('/')}`,
+        },
+        [BucketVersioningKeyFormat.v1]: [{
             gt: `${DbPrefixes.Master}notes/yore.rs${inc(VID_SEP)}`,
             lt: `${DbPrefixes.Master}notes${inc('/')}`,
         }, {
@@ -481,14 +529,20 @@ const tests = [
     }, (e, input) => e.key > input.keyMarker),
 ];
 
-function getTestListing(test, data, vFormat) {
-    return data
+function getTestListing(test, vFormat) {
+    return rawListingData
+        .filter(e => [BucketVersioningKeyFormat.v0,
+                      BucketVersioningKeyFormat.v0mig].includes(vFormat)
+                || e.value !== valuePHD)
         .filter(e => test.filter(e, test.input))
         .map(e => {
-            if (vFormat === 'v0') {
+            if ([BucketVersioningKeyFormat.v0,
+                 BucketVersioningKeyFormat.v0mig].includes(vFormat)) {
                 return e;
             }
-            if (vFormat === 'v1') {
+            if ([BucketVersioningKeyFormat.v0v1,
+                 BucketVersioningKeyFormat.v1mig,
+                 BucketVersioningKeyFormat.v1].includes(vFormat)) {
                 const keyPrefix = e.key.includes(VID_SEP) ?
                       DbPrefixes.Version : DbPrefixes.Master;
                 return {
@@ -500,29 +554,60 @@ function getTestListing(test, data, vFormat) {
         });
 }
 
-['v0', 'v1'].forEach(vFormat => {
+[
+    BucketVersioningKeyFormat.v0,
+    BucketVersioningKeyFormat.v0mig,
+    BucketVersioningKeyFormat.v0v1,
+    BucketVersioningKeyFormat.v1mig,
+    BucketVersioningKeyFormat.v1,
+].forEach(vFormat => {
     describe(`Delimiter All Versions listing algorithm vFormat=${vFormat}`, () => {
         it('Should return good skipping value for DelimiterVersions', () => {
             const delimiter = new DelimiterVersions({ delimiter: '/' });
             for (let i = 0; i < 100; i++) {
+                let key;
+                if ([BucketVersioningKeyFormat.v0v1,
+                     BucketVersioningKeyFormat.v1mig,
+                     BucketVersioningKeyFormat.v1].includes(vFormat)) {
+                    key = `${DbPrefixes.Master}foo/${zpad(i)}`;
+                } else {
+                    key = `foo/${zpad(i)}`;
+                }
                 delimiter.filter({
-                    key: `${vFormat === 'v1' ? DbPrefixes.Master : ''}foo/${zpad(i)}`,
+                    key,
                     value: '{}',
                 });
             }
-            assert.strictEqual(delimiter.skipping(),
-                               `${vFormat === 'v1' ? DbPrefixes.Master : ''}foo/`);
+            let skipping;
+            if ([BucketVersioningKeyFormat.v0v1,
+                 BucketVersioningKeyFormat.v1mig,
+                 BucketVersioningKeyFormat.v1].includes(vFormat)) {
+                skipping = `${DbPrefixes.Master}foo/`;
+            } else {
+                skipping = 'foo/';
+            }
+            assert.strictEqual(delimiter.skipping(), skipping);
         });
 
         tests.forEach(test => {
             it(`Should return metadata listing params to list ${test.name}`, () => {
                 const listing = new DelimiterVersions(test.input, logger, vFormat);
                 const params = listing.genMDParams();
-                assert.deepStrictEqual(params, test.genMDParams[vFormat]);
+                let paramsVFormat;
+                if ([BucketVersioningKeyFormat.v0v1,
+                     BucketVersioningKeyFormat.v1mig,
+                     BucketVersioningKeyFormat.v1].includes(vFormat)) {
+                    // all above vformats are equivalent to v1 when it
+                    // comes to generating md params
+                    paramsVFormat = BucketVersioningKeyFormat.v1;
+                } else {
+                    paramsVFormat = vFormat;
+                }
+                assert.deepStrictEqual(params, test.genMDParams[paramsVFormat]);
             });
             it(`Should list ${test.name}`, () => {
                 // Simulate skip scan done by LevelDB
-                const d = getTestListing(test, dataVersioned[vFormat], vFormat);
+                const d = getTestListing(test, vFormat);
                 const res = performListing(d, DelimiterVersions, test.input, logger, vFormat);
                 assert.deepStrictEqual(res, test.output);
             });

tests/unit/algos/list/tools.js

@@ -2,10 +2,11 @@
 
 const assert = require('assert');
 
-const { checkLimit, inc, listingParamsMasterKeysV0ToV1 } =
+const { checkLimit, inc, listingParamsMasterKeysV0ToV1, listingParamsV0ToV0Mig } =
       require('../../../../lib/algos/list/tools');
 const VSConst = require('../../../../lib/versioning/constants').VersioningConstants;
 const { DbPrefixes } = VSConst;
+const VID_SEP = VSConst.VersionId.Separator;
 
 describe('checkLimit function', () => {
     const tests = [
@@ -102,3 +103,93 @@ describe('listingParamsMasterKeysV0ToV1', () => {
         });
     });
 });
+
+describe('listingParamsV0ToV0Mig', () => {
+    const testCases = [
+        {
+            v0params: {},
+            v0migparams: [{
+                lt: DbPrefixes.V1,
+            }, {
+                gte: inc(DbPrefixes.V1),
+                serial: true,
+            }],
+        }, {
+            v0params: {
+                gte: 'foo/bar',
+                lt: 'foo/bas',
+            },
+            v0migparams: {
+                gte: 'foo/bar',
+                lt: 'foo/bas',
+            },
+        }, {
+            v0params: {
+                gt: `foo/bar${inc(VID_SEP)}`,
+            },
+            v0migparams: [{
+                gt: `foo/bar${inc(VID_SEP)}`,
+                lt: DbPrefixes.V1,
+            }, {
+                gte: inc(DbPrefixes.V1),
+                serial: true,
+            }],
+        }, {
+            v0params: {
+                gt: `foo/bar${VID_SEP}versionId`,
+            },
+            v0migparams: [{
+                gt: `foo/bar${VID_SEP}versionId`,
+                lt: DbPrefixes.V1,
+            }, {
+                gte: inc(DbPrefixes.V1),
+                serial: true,
+            }],
+        }, {
+            v0params: {
+                gt: `foo/bar/baz${VID_SEP}versionId`,
+                lt: 'foo/bas',
+            },
+            v0migparams: {
+                gt: `foo/bar/baz${VID_SEP}versionId`,
+                lt: 'foo/bas',
+            },
+        }, {
+            v0params: {
+                gt: `éléphant rose${VID_SEP}versionId`,
+            },
+            v0migparams: {
+                gt: `éléphant rose${VID_SEP}versionId`,
+            },
+        }, {
+            v0params: {
+                gte: 'éléphant rose',
+                lt: 'éléphant rosf',
+            },
+            v0migparams: {
+                gte: 'éléphant rose',
+                lt: 'éléphant rosf',
+            },
+        }, {
+            v0params: {
+                gt: `${DbPrefixes.V1}foo`,
+            },
+            v0migparams: {
+                gt: inc(DbPrefixes.V1),
+            },
+        }, {
+            v0params: {
+                gte: `${DbPrefixes.V1}foo/`,
+                lt: `${DbPrefixes.V1}foo0`,
+            },
+            v0migparams: {
+                lt: '',
+            },
+        }];
+    testCases.forEach(({ v0params, v0migparams }) => {
+        it(`${JSON.stringify(v0params)} => ${JSON.stringify(v0migparams)}`, () => {
+            const converted = listingParamsV0ToV0Mig(v0params);
+            assert.deepStrictEqual(converted, v0migparams);
+        });
+    });
+});

tests/unit/algos/stream/MergeStream.spec.js

@@ -1,38 +1,6 @@
 const assert = require('assert');
-const stream = require('stream');
 const MergeStream = require('../../../../lib/algos/stream/MergeStream');
-
-class Streamify extends stream.Readable {
-    constructor(objectsToSend, errorAtEnd) {
-        super({ objectMode: true });
-        this._remaining = Array.from(objectsToSend);
-        this._remaining.reverse();
-        this._errorAtEnd = errorAtEnd || false;
-        this._ended = false;
-        this._destroyed = false;
-    }
-
-    _read() {
-        process.nextTick(() => {
-            while (this._remaining.length > 0) {
-                const item = this._remaining.pop();
-                if (!this.push(item)) {
-                    return undefined;
-                }
-            }
-            if (this._errorAtEnd) {
-                return this.emit('error', new Error('OOPS'));
-            }
-            this._ended = true;
-            return this.push(null);
-        });
-    }
-
-    _destroy(err, callback) {
-        this._destroyed = true;
-        callback();
-    }
-}
+const Streamify = require('./Streamify');
 
 function readAll(stream, usePauseResume, cb) {
     const result = [];
@@ -168,12 +136,16 @@ describe('MergeStream', () => {
                       `${testCasePretty(testCase, false)}` +
                       `${usePauseResume ? ' with pause/resume' : ''}` +
                       `${errorAtEnd ? ' with error' : ''}`;
+                const testDescRev =
+                      `${testCasePretty(testCase, true)}` +
+                      `${usePauseResume ? ' with pause/resume' : ''}` +
+                      `${errorAtEnd ? ' with error' : ''}`;
                 it(`should cover ${testDesc}`, done => {
                     testMergeStreamWithIntegers(
                         testCase.stream1, testCase.stream2,
                         usePauseResume, errorAtEnd, done);
                 });
-                it(`should cover ${testDesc}`, done => {
+                it(`should cover ${testDescRev}`, done => {
                     testMergeStreamWithIntegers(
                         testCase.stream2, testCase.stream1,
                         usePauseResume, errorAtEnd, done);

tests/unit/algos/stream/SerialStream.spec.js

@@ -0,0 +1,153 @@
+const assert = require('assert');
+const SerialStream = require('../../../../lib/algos/stream/SerialStream');
+const Streamify = require('./Streamify');
+
+function readAll(stream, usePauseResume, cb) {
+    const result = [];
+    stream.on('data', item => {
+        result.push(item);
+        if (usePauseResume) {
+            stream.pause();
+            setTimeout(() => stream.resume(), 1);
+        }
+    });
+    stream.once('end', () => cb(null, result));
+    stream.once('error', err => cb(err));
+}
+
+function testSerialStreamWithIntegers(contents1, contents2,
+                                     usePauseResume, errorAtEnd, cb) {
+    const expectedItems = contents1.concat(contents2);
+    const serialStream = new SerialStream(
+        new Streamify(contents1, errorAtEnd)
+            .on('error', () => {}),
+        new Streamify(contents2)
+            .on('error', () => {}));
+    readAll(serialStream, usePauseResume, (err, readItems) => {
+        if (errorAtEnd) {
+            assert(err);
+        } else {
+            assert.ifError(err);
+            assert.deepStrictEqual(readItems, expectedItems);
+        }
+        cb();
+    });
+}
+
+function testCasePretty(testCase, reversed) {
+    const desc1 = JSON.stringify(
+        reversed ? testCase.stream2 : testCase.stream1);
+    const desc2 = JSON.stringify(
+        reversed ? testCase.stream1 : testCase.stream2);
+    return `${desc1} concatenated with ${desc2}`;
+}
+
+describe('SerialStream', () => {
+    [
+        {
+            stream1: [],
+            stream2: [],
+        },
+        {
+            stream1: [0],
+            stream2: [],
+        },
+        {
+            stream1: [0, 1, 2, 3, 4],
+            stream2: [],
+        },
+        {
+            stream1: [0],
+            stream2: [1],
+        },
+        {
+            stream1: [1, 2, 3, 4, 5],
+            stream2: [6],
+        },
+        {
+            stream1: [1, 2, 3, 4, 5],
+            stream2: [6, 7, 8, 9, 10],
+        },
+    ].forEach(testCase => {
+        [false, true].forEach(usePauseResume => {
+            [false, true].forEach(errorAtEnd => {
+                const testDesc =
+                      `${testCasePretty(testCase, false)}` +
+                      `${usePauseResume ? ' with pause/resume' : ''}` +
+                      `${errorAtEnd ? ' with error' : ''}`;
+                const testDescRev =
+                      `${testCasePretty(testCase, true)}` +
+                      `${usePauseResume ? ' with pause/resume' : ''}` +
+                      `${errorAtEnd ? ' with error' : ''}`;
+                it(`should cover ${testDesc}`, done => {
+                    testSerialStreamWithIntegers(
+                        testCase.stream1, testCase.stream2,
+                        usePauseResume, errorAtEnd, done);
+                });
+                it(`should cover ${testDescRev}`, done => {
+                    testSerialStreamWithIntegers(
+                        testCase.stream2, testCase.stream1,
+                        usePauseResume, errorAtEnd, done);
+                });
+            });
+        });
+    });
+    [100, 1000, 10000, 100000].forEach(nbEntries => {
+        [false, true].forEach(usePauseResume => {
+            [false, true].forEach(errorAtEnd => {
+                if ((!usePauseResume && !errorAtEnd) || nbEntries <= 1000) {
+                    const fixtureDesc =
+                          `${usePauseResume ? ' with pause/resume' : ''}` +
+                          `${errorAtEnd ? ' with error' : ''}`;
+                    it(`${nbEntries} entries${fixtureDesc}`,
+                    function bigConcatSequential(done) {
+                        this.timeout(10000);
+                        const stream1 = [];
+                        const stream2 = [];
+                        for (let i = 0; i < nbEntries / 2; ++i) {
+                            stream1.push(i);
+                        }
+                        for (let i = nbEntries / 2; i < nbEntries; ++i) {
+                            stream2.push(i);
+                        }
+                        testSerialStreamWithIntegers(
+                            stream1, stream2, usePauseResume, errorAtEnd, done);
+                    });
+                }
+            });
+        });
+    });
+    // with 3 items per input stream, we reach the end of stream even
+    // though destroy() has been called (due to buffering), while with
+    // 100 items input streams are aborted before emitting the 'end'
+    // event, so it's useful to test both cases
+    [3, 100].forEach(nbItemsPerStream => {
+        it(`destroy() should destroy both inner streams with ${nbItemsPerStream} items per stream`,
+        done => {
+            const stream1 = new Streamify(new Array(nbItemsPerStream).fill()
+                                          .map((e, i) => i));
+            const stream2 = new Streamify(new Array(nbItemsPerStream).fill()
+                                          .map((e, i) => nbItemsPerStream + i));
+            const serialStream = new SerialStream(stream1, stream2);
+            serialStream.on('data', item => {
+                if (item === 5) {
+                    serialStream.destroy();
+                    const s1ended = stream1._ended;
+                    const s2ended = stream2._ended;
+                    setTimeout(() => {
+                        if (!s1ended) {
+                            assert(stream1._destroyed);
+                        }
+                        if (!s2ended) {
+                            assert(stream2._destroyed);
+                        }
+                        done();
+                    }, 10);
+                }
+            });
+            serialStream.once('error', err => {
+                assert.fail(`unexpected error: ${err.message}`);
+            });
+        });
+    });
+});

tests/unit/algos/stream/Streamify.js

@@ -0,0 +1,35 @@
+const stream = require('stream');
+
+class Streamify extends stream.Readable {
+    constructor(objectsToSend, errorAtEnd) {
+        super({ objectMode: true });
+        this._remaining = Array.from(objectsToSend);
+        this._remaining.reverse();
+        this._errorAtEnd = errorAtEnd || false;
+        this._ended = false;
+        this._destroyed = false;
+    }
+
+    _read() {
+        process.nextTick(() => {
+            while (this._remaining.length > 0) {
+                const item = this._remaining.pop();
+                if (!this.push(item)) {
+                    return undefined;
+                }
+            }
+            if (this._errorAtEnd) {
+                return this.emit('error', new Error('OOPS'));
+            }
+            this._ended = true;
+            return this.push(null);
+        });
+    }
+
+    _destroy(err, callback) {
+        this._destroyed = true;
+        callback();
+    }
+}
+
+module.exports = Streamify;