Skip MPU shadow buckets

Pre-existing LogConsumer contract uses `null` for initial values,
`undefined` breaks client code assumptions.

lib/storage/metadata/mongoclient/LogConsumer.js

@@ -4,7 +4,7 @@ const stream = require('stream');
 const MongoClient = require('mongodb').MongoClient;
 const { Timestamp } = require('bson');
 
-let lastEndID = undefined;
+let lastEndID = null;
 
 const ops = {
     i: 'put',
@@ -17,12 +17,12 @@ class ListRecordStream extends stream.Transform {
         super({ objectMode: true });
         this.logger = logger;
         this.hasStarted = false;
-        this.start = undefined;
+        this.start = null;
-        this.end = undefined;
+        this.end = null;
-        this.lastUniqID = undefined;
+        this.lastUniqID = null;
         // this.unpublishedListing is true once we pass the oplog that has the
         // start seq timestamp and uniqID 'h'
-        this.unpublishedListing = undefined;
+        this.unpublishedListing = null;
     }
 
     _transform(itemObj, encoding, callback) {
@@ -39,7 +39,7 @@ class ListRecordStream extends stream.Transform {
         // always update to most recent uniqID
         this.lastUniqID = itemObj.h.toString();
 
-        if (this.end === undefined || itemObj.ts.toNumber() > this.end) {
+        if (this.end === null || itemObj.ts.toNumber() > this.end) {
             this.end = itemObj.ts.toNumber();
         }
 

lib/storage/metadata/mongoclient/MongoClientInterface.js

@@ -868,7 +868,8 @@ class MongoClientInterface {
                 if (value.name === METASTORE ||
                     value.name === INFOSTORE ||
                     value.name === USERSBUCKET ||
-                    value.name === PENSIEVE
+                    value.name === PENSIEVE ||
+                    value.name.startsWith(constants.mpuBucketPrefix)
                 ) {
                     // skip
                     return next();

package.json

@@ -3,7 +3,7 @@
   "engines": {
     "node": "6.9.5"
   },
-  "version": "7.4.0",
+  "version": "7.4.0-mongologreader",
   "description": "Common utilities for the S3 project components",
   "main": "index.js",
   "repository": {