SERVER-37505 Run applyOps with prepare: true in its own batch in MultiApplier.

2 files changed, 9 insertions, 3 deletions

diff --git a/src/mongo/db/repl/apply_ops.cpp b/src/mongo/db/repl/apply_ops.cpp
index 3530c71aca7..5d349d92303 100644
--- a/src/mongo/db/repl/apply_ops.cpp
+++ b/src/mongo/db/repl/apply_ops.cpp
@@ -276,10 +276,15 @@ Status _applyPrepareTransaction(OperationContext* opCtx,
                                 int* numApplied,
                                 BSONArrayBuilder* opsBuilder,
                                 const OpTime& optime) {
-    // Only run on secondary.
+    // Return error if run via applyOps command.
     uassert(50945,
             "applyOps with prepared flag is only used internally by secondaries.",
-            oplogApplicationMode == repl::OplogApplication::Mode::kSecondary);
+            oplogApplicationMode != repl::OplogApplication::Mode::kApplyOpsCmd);
+
+    // TODO: SERVER-35879 Only run on secondary until we support replication recovery and initial
+    // sync.
+    invariant(oplogApplicationMode == repl::OplogApplication::Mode::kSecondary);
+
     uassert(
         50946,
         "applyOps with prepared must only include CRUD operations and cannot have precondition.",
diff --git a/src/mongo/db/repl/oplog_applier.cpp b/src/mongo/db/repl/oplog_applier.cpp
index e7c5160f902..3b86518fd7c 100644
--- a/src/mongo/db/repl/oplog_applier.cpp
+++ b/src/mongo/db/repl/oplog_applier.cpp
@@ -179,7 +179,8 @@ StatusWith<OplogApplier::Operations> OplogApplier::getNextApplierBatch(
         // Commands must be processed one at a time. The only exception to this is applyOps because
         // applyOps oplog entries are effectively containers for CRUD operations. Therefore, it is
         // safe to batch applyOps commands with CRUD operations when reading from the oplog buffer.
-        if (entry.isCommand() && entry.getCommandType() != OplogEntry::CommandType::kApplyOps) {
+        if (entry.isCommand() && (entry.getCommandType() != OplogEntry::CommandType::kApplyOps ||
+                                  entry.shouldPrepare())) {
             if (ops.empty()) {
                 // Apply commands one-at-a-time.
                 ops.push_back(std::move(entry));