SERVER-35879 Deal with commitTransaction oplog entries during startup recovery

1 files changed, 29 insertions, 1 deletions

diff --git a/src/mongo/db/repl/oplog.cpp b/src/mongo/db/repl/oplog.cpp
index 43ea709440a..bd41e12bd1e 100644
--- a/src/mongo/db/repl/oplog.cpp
+++ b/src/mongo/db/repl/oplog.cpp
@@ -86,6 +86,7 @@
 #include "mongo/db/stats/counters.h"
 #include "mongo/db/storage/storage_engine.h"
 #include "mongo/db/storage/storage_options.h"
+#include "mongo/db/transaction_history_iterator.h"
 #include "mongo/db/transaction_participant.h"
 #include "mongo/platform/random.h"
 #include "mongo/scripting/engine.h"
@@ -1010,7 +1011,34 @@ std::map<std::string, ApplyOpMetadata> opsMap = {
          BSONObj& cmd,
          const OpTime& opTime,
          const OplogEntry& entry,
-         OplogApplication::Mode mode) -> Status { return Status::OK(); }}},
+         OplogApplication::Mode mode) -> Status {
+         if (mode == OplogApplication::Mode::kRecovering) {
+             const auto replCoord = ReplicationCoordinator::get(opCtx);
+             const auto recoveryTimestamp = replCoord->getRecoveryTimestamp();
+             invariant(recoveryTimestamp);
+
+             // If the commitTimestamp is before the recoveryTimestamp, then the data already
+             // reflects the operations from the transaction.
+             const auto commitTimestamp = cmd["commitTimestamp"].timestamp();
+             if (recoveryTimestamp.get() > commitTimestamp) {
+                 return Status::OK();
+             }
+
+             // Get the corresponding prepareTransaction oplog entry.
+             TransactionHistoryIterator iter(opTime);
+             invariant(iter.hasNext());
+             const auto commitOplogEntry = iter.next(opCtx);
+             invariant(iter.hasNext());
+             const auto prepareOplogEntry = iter.next(opCtx);
+
+             // Transform prepare command into a normal applyOps command.
+             const auto prepareCmd = prepareOplogEntry.getOperationToApply().removeField("prepare");
+
+             BSONObjBuilder resultWeDontCareAbout;
+             return applyOps(opCtx, nsToDatabase(ns), prepareCmd, mode, &resultWeDontCareAbout);
+         }
+         return Status::OK();
+     }}},
     {"abortTransaction",
      {[](OperationContext* opCtx,
          const char* ns,