Status applyCommitTransaction(OperationContext* opCtx,
const OplogEntry& entry,
repl::OplogApplication::Mode mode) {
// Return error if run via applyOps command.
uassert(50987,
"commitTransaction is only used internally by secondaries.",
mode != repl::OplogApplication::Mode::kApplyOpsCmd);
IDLParserErrorContext ctx("commitTransaction");
auto commitOplogEntryOpTime = entry.getOpTime();
auto commitCommand = CommitTransactionOplogObject::parse(ctx, entry.getObject());
const bool prepared = !commitCommand.getPrepared() || *commitCommand.getPrepared();
if (!prepared)
return Status::OK();
invariant(commitCommand.getCommitTimestamp());
if (mode == repl::OplogApplication::Mode::kRecovering ||
mode == repl::OplogApplication::Mode::kInitialSync) {
return _applyTransactionFromOplogChain(opCtx,
entry,
mode,
*commitCommand.getCommitTimestamp(),
commitOplogEntryOpTime.getTimestamp());
}
invariant(mode == repl::OplogApplication::Mode::kSecondary);
// Transaction operations are in its own batch, so we can modify their opCtx.
invariant(entry.getSessionId());
invariant(entry.getTxnNumber());
opCtx->setLogicalSessionId(*entry.getSessionId());
opCtx->setTxnNumber(*entry.getTxnNumber());
// The write on transaction table may be applied concurrently, so refreshing state
// from disk may read that write, causing starting a new transaction on an existing
// txnNumber. Thus, we start a new transaction without refreshing state from disk.
MongoDOperationContextSessionWithoutRefresh sessionCheckout(opCtx);
auto transaction = TransactionParticipant::get(opCtx);
invariant(transaction);
transaction.unstashTransactionResources(opCtx, "commitTransaction");
transaction.commitPreparedTransaction(
opCtx, *commitCommand.getCommitTimestamp(), commitOplogEntryOpTime);
return Status::OK();
}
StatusWith<std::set<NamespaceString>> RollbackImpl::_namespacesForOp(const OplogEntry& oplogEntry) {
NamespaceString opNss = oplogEntry.getNamespace();
OpTypeEnum opType = oplogEntry.getOpType();
std::set<NamespaceString> namespaces;
// No namespaces for a no-op.
if (opType == OpTypeEnum::kNoop) {
return std::set<NamespaceString>();
}
// CRUD ops have the proper namespace in the operation 'ns' field.
if (opType == OpTypeEnum::kInsert || opType == OpTypeEnum::kUpdate ||
opType == OpTypeEnum::kDelete) {
return std::set<NamespaceString>({opNss});
}
// If the operation is a command, then we need to extract the appropriate namespaces from the
// command object, as opposed to just using the 'ns' field of the oplog entry itself.
if (opType == OpTypeEnum::kCommand) {
auto obj = oplogEntry.getObject();
auto firstElem = obj.firstElement();
// Does not handle 'applyOps' entries.
invariant(oplogEntry.getCommandType() != OplogEntry::CommandType::kApplyOps,
"_namespacesForOp does not handle 'applyOps' oplog entries.");
switch (oplogEntry.getCommandType()) {
case OplogEntry::CommandType::kRenameCollection: {
// Add both the 'from' and 'to' namespaces.
namespaces.insert(NamespaceString(firstElem.valuestrsafe()));
namespaces.insert(NamespaceString(obj.getStringField("to")));
break;
}
case OplogEntry::CommandType::kDropDatabase: {
// There is no specific namespace to save for a drop database operation.
break;
}
case OplogEntry::CommandType::kDbCheck:
case OplogEntry::CommandType::kConvertToCapped:
case OplogEntry::CommandType::kEmptyCapped: {
// These commands do not need to be supported by rollback. 'convertToCapped' should
// always be converted to lower level DDL operations, and 'emptycapped' is a
// testing-only command.
std::string message = str::stream() << "Encountered unsupported command type '"
<< firstElem.fieldName()
<< "' during rollback.";
return Status(ErrorCodes::UnrecoverableRollbackError, message);
}
case OplogEntry::CommandType::kCreate:
case OplogEntry::CommandType::kDrop:
case OplogEntry::CommandType::kCreateIndexes:
case OplogEntry::CommandType::kDropIndexes:
case OplogEntry::CommandType::kCollMod: {
// For all other command types, we should be able to parse the collection name from
// the first command argument.
try {
auto cmdNss = CommandHelpers::parseNsCollectionRequired(opNss.db(), obj);
namespaces.insert(cmdNss);
} catch (const DBException& ex) {
return ex.toStatus();
}
break;
}
case OplogEntry::CommandType::kApplyOps:
default:
// Every possible command type should be handled above.
MONGO_UNREACHABLE
}
}
