SERVER-12515 Unable to move hashed shard key chunks created by numInitialChunks

3 files changed, 96 insertions, 3 deletions

diff --git a/src/mongo/s/collection_metadata.cpp b/src/mongo/s/collection_metadata.cpp
index f49bc911c40..e3e42e84a2b 100644
--- a/src/mongo/s/collection_metadata.cpp
+++ b/src/mongo/s/collection_metadata.cpp
@@ -337,8 +337,9 @@ namespace mongo {
         for ( vector<BSONObj>::const_iterator it = splitKeys.begin(); it != splitKeys.end();
                 ++it ) {
             BSONObj split = *it;
-            metadata->_chunksMap[chunk.getMin()] = split.getOwned();
-            metadata->_chunksMap.insert( make_pair( split.getOwned(), chunk.getMax().getOwned() ) );
+            dassert(split.woCompare(startKey) > 0);
+            metadata->_chunksMap[startKey] = split.getOwned();
+            metadata->_chunksMap.insert( make_pair( split.getOwned(), chunk.getMax().getOwned() ));
             metadata->_shardVersion.incMinor();
             startKey = split;
         }
diff --git a/src/mongo/s/collection_metadata.h b/src/mongo/s/collection_metadata.h
index 8f4588b789b..9916e41c185 100644
--- a/src/mongo/s/collection_metadata.h
+++ b/src/mongo/s/collection_metadata.h
@@ -102,12 +102,14 @@ namespace mongo {
 
         /**
          * Returns a new metadata's instance by splitting an existing 'chunk' at the points
-         * describe by 'splitKeys'. The first resulting chunk will have 'newShardVersion' and
+         * described by 'splitKeys'. The first resulting chunk will have 'newShardVersion' and
          * subsequent one would have that with the minor version incremented at each chunk. The
          * caller owns the metadata.
          *
          * If a new metadata can't be created, returns NULL and fills in 'errMsg', if it was
          * provided.
+         *
+         * Note: 'splitKeys' must be sorted in ascending order.
          */
         CollectionMetadata* cloneSplit( const ChunkType& chunk,
                                         const vector<BSONObj>& splitKeys,
diff --git a/src/mongo/s/collection_metadata_test.cpp b/src/mongo/s/collection_metadata_test.cpp
index 10fd97a8f5e..b2cdd74aa99 100644
--- a/src/mongo/s/collection_metadata_test.cpp
+++ b/src/mongo/s/collection_metadata_test.cpp
@@ -651,6 +651,96 @@ namespace {
         ASSERT( !cloned->keyIsPending(BSON( "a" << 35 )) );
     }
 
+    TEST_F(SingleChunkFixture, SingleSplit) {
+        string errMsg;
+        ChunkType chunk;
+        scoped_ptr<CollectionMetadata> cloned;
+
+        chunk.setMin( BSON("a" << 10) );
+        chunk.setMax( BSON("a" << 20) );
+
+        vector<BSONObj> splitPoints;
+        splitPoints.push_back( BSON("a" << 14) );
+
+        ChunkVersion version;
+        getCollMetadata().getCollVersion().cloneTo( &version );
+        version.incMinor();
+
+        cloned.reset( getCollMetadata().cloneSplit( chunk,
+                                          splitPoints,
+                                          version,
+                                          &errMsg ) );
+
+        ASSERT_EQUALS( errMsg, "" );
+        ASSERT( cloned != NULL );
+
+        ChunkVersion newVersion( cloned->getCollVersion() );
+        ASSERT_EQUALS( version.epoch(), newVersion.epoch() );
+        ASSERT_EQUALS( version.majorVersion(), newVersion.majorVersion() );
+        ASSERT_EQUALS( version.minorVersion() + 1, newVersion.minorVersion() );
+
+        chunk.clear();
+        ASSERT( cloned->getNextChunk(BSON("a" << MINKEY), &chunk) );
+        ASSERT( chunk.getMin().woCompare( BSON("a" << 10) ) == 0 );
+        ASSERT( chunk.getMax().woCompare( BSON("a" << 14) ) == 0 );
+
+        chunk.clear();
+        ASSERT( cloned->getNextChunk(BSON("a" << 14), &chunk) );
+        ASSERT( chunk.getMin().woCompare( BSON("a" << 14) ) == 0 );
+        ASSERT( chunk.getMax().woCompare( BSON("a" << 20) ) == 0 );
+
+        chunk.clear();
+        ASSERT_FALSE( cloned->getNextChunk(BSON("a" << 20), &chunk) );
+    }
+
+    TEST_F(SingleChunkFixture, MultiSplit) {
+        string errMsg;
+        ChunkType chunk;
+        scoped_ptr<CollectionMetadata> cloned;
+
+        chunk.setMin( BSON("a" << 10) );
+        chunk.setMax( BSON("a" << 20) );
+
+        vector<BSONObj> splitPoints;
+        splitPoints.push_back( BSON("a" << 14) );
+        splitPoints.push_back( BSON("a" << 16) );
+
+        ChunkVersion version;
+        getCollMetadata().getCollVersion().cloneTo( &version );
+        version.incMinor();
+
+        cloned.reset( getCollMetadata().cloneSplit( chunk,
+                                          splitPoints,
+                                          version,
+                                          &errMsg ) );
+
+        ASSERT_EQUALS( errMsg, "" );
+        ASSERT( cloned != NULL );
+
+        ChunkVersion newVersion( cloned->getCollVersion() );
+        ASSERT_EQUALS( version.epoch(), newVersion.epoch() );
+        ASSERT_EQUALS( version.majorVersion(), newVersion.majorVersion() );
+        ASSERT_EQUALS( version.minorVersion() + 2, newVersion.minorVersion() );
+
+        chunk.clear();
+        ASSERT( cloned->getNextChunk(BSON("a" << MINKEY), &chunk) );
+        ASSERT( chunk.getMin().woCompare( BSON("a" << 10) ) == 0 );
+        ASSERT( chunk.getMax().woCompare( BSON("a" << 14) ) == 0 );
+
+        chunk.clear();
+        ASSERT( cloned->getNextChunk(BSON("a" << 14), &chunk) );
+        ASSERT( chunk.getMin().woCompare( BSON("a" << 14) ) == 0 );
+        ASSERT( chunk.getMax().woCompare( BSON("a" << 16) ) == 0 );
+
+        chunk.clear();
+        ASSERT( cloned->getNextChunk(BSON("a" << 16), &chunk) );
+        ASSERT( chunk.getMin().woCompare( BSON("a" << 16) ) == 0 );
+        ASSERT( chunk.getMax().woCompare( BSON("a" << 20) ) == 0 );
+
+        chunk.clear();
+        ASSERT_FALSE( cloned->getNextChunk(BSON("a" << 20), &chunk) );
+    }
+
     TEST_F(SingleChunkFixture, SplitChunkWithPending) {
 
         string errMsg;