SERVER-41245: Add RetryableWriteError error label

1 files changed, 139 insertions, 0 deletions

diff --git a/src/mongo/db/error_labels.cpp b/src/mongo/db/error_labels.cpp
new file mode 100644
index 00000000000..d56ba6dd82d
--- /dev/null
+++ b/src/mongo/db/error_labels.cpp
@@ -0,0 +1,139 @@
+/**
+ *    Copyright (C) 2018-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#include "mongo/db/error_labels.h"
+
+namespace mongo {
+
+bool ErrorLabelBuilder::isTransientTransactionError() const {
+    // Note that we only apply the TransientTransactionError label if the "autocommit" field is
+    // present in the session options. When present, "autocommit" will always be false, so we
+    // don't check its value. There is no point in returning TransientTransactionError label if
+    // we have already tried to abort it. An error code for which isTransientTransactionError()
+    // is true indicates a transaction failure with no persistent side effects.
+    return _code && _sessionOptions.getTxnNumber() && _sessionOptions.getAutocommit() &&
+        mongo::isTransientTransactionError(_code.get(), _wcCode != boost::none, _isCommitOrAbort());
+}
+
+bool ErrorLabelBuilder::isRetryableWriteError() const {
+    // Do not return RetryableWriteError labels to internal clients (e.g. mongos).
+    if (_isInternalClient) {
+        return false;
+    }
+
+    auto isRetryableWrite = [&]() {
+        return _sessionOptions.getTxnNumber() && !_sessionOptions.getAutocommit();
+    };
+
+    auto isTransactionCommitOrAbort = [&]() {
+        return _sessionOptions.getTxnNumber() && _sessionOptions.getAutocommit() &&
+            _isCommitOrAbort();
+    };
+
+    // Return with RetryableWriteError label on retryable error codes for retryable writes or
+    // transactions commit/abort.
+    if (isRetryableWrite() || isTransactionCommitOrAbort()) {
+        if ((_code && ErrorCodes::isRetriableError(_code.get())) ||
+            (_wcCode && ErrorCodes::isRetriableError(_wcCode.get()))) {
+            return true;
+        }
+    }
+    return false;
+}
+
+bool ErrorLabelBuilder::isNonResumableChangeStreamError() const {
+    return _code && ErrorCodes::isNonResumableChangeStreamError(_code.get());
+}
+
+void ErrorLabelBuilder::build(BSONArrayBuilder& labels) const {
+    // PLEASE CONSULT DRIVERS BEFORE ADDING NEW ERROR LABELS.
+    bool hasTransientTransactionError = false;
+    if (isTransientTransactionError()) {
+        labels << ErrorLabel::kTransientTransaction;
+        hasTransientTransactionError = true;
+    }
+    if (isRetryableWriteError()) {
+        // RetryableWriteError and TransientTransactionError are mutually exclusive.
+        invariant(!hasTransientTransactionError);
+        labels << ErrorLabel::kRetryableWrite;
+    }
+    if (isNonResumableChangeStreamError()) {
+        labels << ErrorLabel::kNonResumableChangeStream;
+    }
+    return;
+}
+
+bool ErrorLabelBuilder::_isCommitOrAbort() const {
+    return _commandName == "commitTransaction" || _commandName == "coordinateCommitTransaction" ||
+        _commandName == "abortTransaction";
+}
+
+BSONObj getErrorLabels(const OperationSessionInfoFromClient& sessionOptions,
+                       const std::string& commandName,
+                       boost::optional<ErrorCodes::Error> code,
+                       boost::optional<ErrorCodes::Error> wcCode,
+                       bool isInternalClient) {
+    BSONArrayBuilder labelArray;
+
+    ErrorLabelBuilder labelBuilder(sessionOptions, commandName, code, wcCode, isInternalClient);
+    labelBuilder.build(labelArray);
+
+    return (labelArray.arrSize() > 0) ? BSON("errorLabels" << labelArray.arr()) : BSONObj();
+}
+
+bool isTransientTransactionError(ErrorCodes::Error code,
+                                 bool hasWriteConcernError,
+                                 bool isCommitOrAbort) {
+    bool isTransient;
+    switch (code) {
+        case ErrorCodes::WriteConflict:
+        case ErrorCodes::LockTimeout:
+        case ErrorCodes::PreparedTransactionInProgress:
+            isTransient = true;
+            break;
+        default:
+            isTransient = false;
+            break;
+    }
+
+    isTransient |= ErrorCodes::isSnapshotError(code) || ErrorCodes::isNeedRetargettingError(code) ||
+        code == ErrorCodes::StaleDbVersion;
+
+    if (isCommitOrAbort) {
+        // On NoSuchTransaction it's safe to retry the whole transaction only if the data cannot be
+        // rolled back.
+        isTransient |= code == ErrorCodes::NoSuchTransaction && !hasWriteConcernError;
+    } else {
+        isTransient |= ErrorCodes::isRetriableError(code) || code == ErrorCodes::NoSuchTransaction;
+    }
+
+    return isTransient;
+}
+
+}  // namespace mongo