SERVER-41188 Remove support for explicit prepare oplog entry on secondary

11 files changed, 15 insertions, 56 deletions

diff --git a/jstests/replsets/initial_sync_fetch_from_oldest_active_transaction_timestamp.js b/jstests/replsets/initial_sync_fetch_from_oldest_active_transaction_timestamp.js
index cfc5a252646..a15f5290ea6 100644
--- a/jstests/replsets/initial_sync_fetch_from_oldest_active_transaction_timestamp.js
+++ b/jstests/replsets/initial_sync_fetch_from_oldest_active_transaction_timestamp.js
@@ -6,7 +6,7 @@
  *
  * To make sure that it is applying from the correct point, the test prepares a transaction before
  * the beginFetchingTimestamp and commits it before the beginApplyingTimestamp. Since the
- * transaction is not active by the time initial sync begins, its prepareTransaction oplog entry
+ * transaction is not active by the time initial sync begins, its prepare oplog entry
  * won't be fetched during oplog application and trying to apply the commitTransaction oplog entry
  * will cause initial sync to fail.
  *
@@ -71,7 +71,7 @@
 
     // Commit the first transaction so that we have an operation that is fetched during initial sync
     // but should not be applied. If this is applied, initial sync will fail because while trying to
-    // apply the commitTransaction oplog entry, it will fail to get the prepareTransaction oplog
+    // apply the commitTransaction oplog entry, it will fail to get the prepare oplog
     // entry since its optime is before the beginFetchingTimestamp. Doing another operation will
     // also cause the beginApplyingTimestamp to be different from the beginFetchingTimestamp. Note
     // that since the beginApplyingTimestamp is the timestamp after which operations are applied
diff --git a/src/mongo/db/auth/role_graph_update.cpp b/src/mongo/db/auth/role_graph_update.cpp
index b5956069f85..02c89f36bd7 100644
--- a/src/mongo/db/auth/role_graph_update.cpp
+++ b/src/mongo/db/auth/role_graph_update.cpp
@@ -297,8 +297,7 @@ Status handleOplogCommand(RoleGraph* roleGraph, const BSONObj& cmdObj) {
         return Status::OK();
     }
 
-    if (cmdName == "commitTransaction" || cmdName == "abortTransaction" ||
-        cmdName == "prepareTransaction") {
+    if (cmdName == "commitTransaction" || cmdName == "abortTransaction") {
         return Status::OK();
     }
 
diff --git a/src/mongo/db/commands/txn_cmds.idl b/src/mongo/db/commands/txn_cmds.idl
index 0e58d8302bd..c9a479c63c3 100644
--- a/src/mongo/db/commands/txn_cmds.idl
+++ b/src/mongo/db/commands/txn_cmds.idl
@@ -77,13 +77,6 @@ structs:
                 type: int
                 default: 1
 
-    PrepareTransactionOplogObject:
-        description: A document representing the 'o' field of a 'prepareTransaction' oplog entry.
-        fields:
-            prepareTransaction:
-                type: int
-                default: 1
-
 commands:
     commitTransaction:
         description: "commitTransaction Command"
diff --git a/src/mongo/db/repl/oplog.cpp b/src/mongo/db/repl/oplog.cpp
index 1c785e6186b..2e9190198bf 100644
--- a/src/mongo/db/repl/oplog.cpp
+++ b/src/mongo/db/repl/oplog.cpp
@@ -1238,17 +1238,6 @@ const StringMap<ApplyOpMetadata> kOpsMap = {
          boost::optional<Timestamp> stableTimestampForRecovery) -> Status {
          return applyCommitTransaction(opCtx, entry, mode);
      }}},
-    {"prepareTransaction",
-     {[](OperationContext* opCtx,
-         const char* ns,
-         const BSONElement& ui,
-         BSONObj& cmd,
-         const OpTime& opTime,
-         const OplogEntry& entry,
-         OplogApplication::Mode mode,
-         boost::optional<Timestamp> stableTimestampForRecovery) -> Status {
-         return applyPrepareTransaction(opCtx, entry, mode);
-     }}},
     {"abortTransaction",
      {[](OperationContext* opCtx,
          const char* ns,
@@ -1823,12 +1812,8 @@ Status applyCommand_inlock(OperationContext* opCtx,
     // for each collection dropped. 'applyOps' and 'commitTransaction' will try to apply each
     // individual operation, and those will be caught then if they are a problem. 'abortTransaction'
     // won't ever change the server configuration collection.
-    std::vector<std::string> whitelistedOps{"dropDatabase",
-                                            "applyOps",
-                                            "dbCheck",
-                                            "commitTransaction",
-                                            "abortTransaction",
-                                            "prepareTransaction"};
+    std::vector<std::string> whitelistedOps{
+        "dropDatabase", "applyOps", "dbCheck", "commitTransaction", "abortTransaction"};
     if ((mode == OplogApplication::Mode::kInitialSync) &&
         (std::find(whitelistedOps.begin(), whitelistedOps.end(), o.firstElementFieldName()) ==
          whitelistedOps.end()) &&
@@ -1859,8 +1844,9 @@ Status applyCommand_inlock(OperationContext* opCtx,
 
         // Don't assign commit timestamp for transaction commands.
         const StringData commandName(o.firstElementFieldName());
-        if (entry.shouldPrepare() || commandName == "abortTransaction" ||
-            commandName == "commitTransaction" || commandName == "prepareTransaction")
+        if (entry.shouldPrepare() ||
+            entry.getCommandType() == OplogEntry::CommandType::kCommitTransaction ||
+            entry.getCommandType() == OplogEntry::CommandType::kAbortTransaction)
             return false;
 
         switch (replMode) {
diff --git a/src/mongo/db/repl/oplog_entry.cpp b/src/mongo/db/repl/oplog_entry.cpp
index 8bdce328f4a..6d549dd1965 100644
--- a/src/mongo/db/repl/oplog_entry.cpp
+++ b/src/mongo/db/repl/oplog_entry.cpp
@@ -78,8 +78,6 @@ OplogEntry::CommandType parseCommandType(const BSONObj& objectField) {
         return OplogEntry::CommandType::kCommitTransaction;
     } else if (commandString == "abortTransaction") {
         return OplogEntry::CommandType::kAbortTransaction;
-    } else if (commandString == "prepareTransaction") {
-        return OplogEntry::CommandType::kPrepareTransaction;
     } else {
         uasserted(ErrorCodes::BadValue,
                   str::stream() << "Unknown oplog entry command type: " << commandString
diff --git a/src/mongo/db/repl/oplog_entry.h b/src/mongo/db/repl/oplog_entry.h
index 1574a995bdb..7337d79165e 100644
--- a/src/mongo/db/repl/oplog_entry.h
+++ b/src/mongo/db/repl/oplog_entry.h
@@ -89,7 +89,6 @@ public:
         kDropIndexes,
         kCommitTransaction,
         kAbortTransaction,
-        kPrepareTransaction,
     };
 
     // Current oplog version, should be the value of the v field in all oplog entries.
diff --git a/src/mongo/db/repl/replication_recovery_test.cpp b/src/mongo/db/repl/replication_recovery_test.cpp
index dba35e6f823..f85d0de2252 100644
--- a/src/mongo/db/repl/replication_recovery_test.cpp
+++ b/src/mongo/db/repl/replication_recovery_test.cpp
@@ -244,7 +244,7 @@ repl::OplogEntry _makeOplogEntry(repl::OpTime opTime,
 }
 
 /**
- * Creates a prepareTransaction, commitTransaction or abortTransaction OplogEntry.
+ * Creates a transaction oplog entry.
  */
 repl::OplogEntry _makeTransactionOplogEntry(repl::OpTime opTime,
                                             repl::OpTypeEnum opType,
diff --git a/src/mongo/db/repl/rollback_impl.cpp b/src/mongo/db/repl/rollback_impl.cpp
index 25e82217d30..9bdc79ffbf2 100644
--- a/src/mongo/db/repl/rollback_impl.cpp
+++ b/src/mongo/db/repl/rollback_impl.cpp
@@ -438,7 +438,6 @@ StatusWith<std::set<NamespaceString>> RollbackImpl::_namespacesForOp(const Oplog
                 break;
             }
             case OplogEntry::CommandType::kCommitTransaction:
-            case OplogEntry::CommandType::kPrepareTransaction:
             case OplogEntry::CommandType::kAbortTransaction: {
                 break;
             }
diff --git a/src/mongo/db/repl/session_update_tracker.cpp b/src/mongo/db/repl/session_update_tracker.cpp
index 176135f5bed..28ed0f215f0 100644
--- a/src/mongo/db/repl/session_update_tracker.cpp
+++ b/src/mongo/db/repl/session_update_tracker.cpp
@@ -115,7 +115,6 @@ bool isTransactionEntry(OplogEntry entry) {
     }
 
     return entry.isPartialTransaction() ||
-        entry.getCommandType() == repl::OplogEntry::CommandType::kPrepareTransaction ||
         entry.getCommandType() == repl::OplogEntry::CommandType::kAbortTransaction ||
         entry.getCommandType() == repl::OplogEntry::CommandType::kCommitTransaction ||
         entry.getCommandType() == repl::OplogEntry::CommandType::kApplyOps;
@@ -301,17 +300,6 @@ boost::optional<OplogEntry> SessionUpdateTracker::_createTransactionTableUpdateF
                     newTxnRecord.setState(DurableTxnStateEnum::kCommitted);
                 }
                 break;
-            case repl::OplogEntry::CommandType::kPrepareTransaction:
-                newTxnRecord.setState(DurableTxnStateEnum::kPrepared);
-                if (entry.getPrevWriteOpTimeInTransaction()->isNull()) {
-                    // The 'prepareTransaction' entry is the first operation of the transaction.
-                    newTxnRecord.setStartOpTime(entry.getOpTime());
-                } else {
-                    // Update the transaction record using $set to avoid overwriting the
-                    // startOpTime.
-                    return BSON("$set" << newTxnRecord.toBSON());
-                }
-                break;
             case repl::OplogEntry::CommandType::kCommitTransaction:
                 newTxnRecord.setState(DurableTxnStateEnum::kCommitted);
                 break;
diff --git a/src/mongo/db/repl/transaction_oplog_application.cpp b/src/mongo/db/repl/transaction_oplog_application.cpp
index 360024e5405..c5fbb2f7177 100644
--- a/src/mongo/db/repl/transaction_oplog_application.cpp
+++ b/src/mongo/db/repl/transaction_oplog_application.cpp
@@ -74,11 +74,8 @@ Status _applyOperationsForTransaction(OperationContext* opCtx,
 }
 
 /**
- * Helper that will find the previous oplog entry for that transaction, then for old-style applyOps
- * entries, will transform it to be a normal applyOps command and applies the oplog entry.
- *
- * For new-style transactions, with multiple oplog entries, will then read the entire set of oplog
- * entries for the transaction and apply each of them.
+ * Helper that will read the entire sequence of oplog entries for the transaction and apply each of
+ * them.
  *
  * Currently used for oplog application of a commitTransaction oplog entry during recovery, rollback
  * and initial sync.
@@ -96,7 +93,7 @@ Status _applyTransactionFromOplogChain(OperationContext* opCtx,
         // Traverse the oplog chain with its own snapshot and read timestamp.
         ReadSourceScope readSourceScope(opCtx);
 
-        // Get the corresponding prepareTransaction oplog entry.
+        // Get the corresponding prepare applyOps oplog entry.
         const auto prepareOpTime = entry.getPrevWriteOpTimeInTransaction();
         invariant(prepareOpTime);
         TransactionHistoryIterator iter(prepareOpTime.get());
@@ -213,7 +210,7 @@ Status applyAbortTransaction(OperationContext* opCtx,
 repl::MultiApplier::Operations readTransactionOperationsFromOplogChain(
     OperationContext* opCtx,
     const OplogEntry& commitOrPrepare,
-    const std::vector<OplogEntry*> cachedOps) {
+    const std::vector<OplogEntry*>& cachedOps) {
     repl::MultiApplier::Operations ops;
 
     // Get the previous oplog entry.
@@ -382,7 +379,7 @@ Status applyPrepareTransaction(OperationContext* opCtx,
 
     // Return error if run via applyOps command.
     uassert(51145,
-            "prepareTransaction oplog entry is only used internally by secondaries.",
+            "prepare applyOps oplog entry is only used internally by secondaries.",
             oplogApplicationMode != repl::OplogApplication::Mode::kApplyOpsCmd);
 
     invariant(oplogApplicationMode == repl::OplogApplication::Mode::kSecondary);
diff --git a/src/mongo/db/repl/transaction_oplog_application.h b/src/mongo/db/repl/transaction_oplog_application.h
index 09607e820f2..dc145d2c701 100644
--- a/src/mongo/db/repl/transaction_oplog_application.h
+++ b/src/mongo/db/repl/transaction_oplog_application.h
@@ -57,7 +57,7 @@ Status applyAbortTransaction(OperationContext* opCtx,
 repl::MultiApplier::Operations readTransactionOperationsFromOplogChain(
     OperationContext* opCtx,
     const repl::OplogEntry& entry,
-    const std::vector<repl::OplogEntry*> cachedOps);
+    const std::vector<repl::OplogEntry*>& cachedOps);
 
 /**
  * Apply `prepareTransaction` oplog entry.