SERVER-19855 Include min OpTime with shard version

This change adds the OpTime of the chunk manager as of the time its cached
metadata was loaded along with each versioned request sent from MongoS.
This includes write commands and the setShardVersion command.

The OpTime is only sent as part of this change. There will be a follow-up
change to add code to interpret this information on the MongoD side.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/mongo/s/chunk_manager.h b/src/mongo/s/chunk_manager.h
index 0ca94237920..23440fced18 100644
--- a/src/mongo/s/chunk_manager.h
+++ b/src/mongo/s/chunk_manager.h
@@ -44,6 +44,10 @@ class CollectionType;
 struct QuerySolutionNode;
 class OperationContext;
 
+namespace repl {
+class OpTime;
+}
+
 typedef std::shared_ptr<ChunkManager> ChunkManagerPtr;
 
 // The key for the map is max for each Chunk or ChunkRange
@@ -154,6 +158,11 @@ public:
         return _sequenceNumber;
     }
 
+    /**
+     * Returns the latest op time from when this chunk manager's data was loaded.
+     */
+    repl::OpTime getConfigOpTime() const;
+
     //
     // After constructor is invoked, we need to call loadExistingRanges.  If this is a new
     // sharded collection, we can call createFirstChunks first.