SERVER-35154 Propagate JS exceptions through ScopedThread#join().

This makes it so that if the ScopedThread exited due to an uncaught
JavaScript exception, then calling .join() or .returnData() on it throws
a JavaScript exception with the error message and stacktrace intact.

1 files changed, 75 insertions, 0 deletions

diff --git a/src/mongo/scripting/jsexception.cpp b/src/mongo/scripting/jsexception.cpp
new file mode 100644
index 00000000000..51671963e6a
--- /dev/null
+++ b/src/mongo/scripting/jsexception.cpp
@@ -0,0 +1,75 @@
+/**
+ * Copyright (C) 2018 MongoDB Inc.
+ *
+ * This program is free software: you can redistribute it and/or  modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * 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 GNU Affero General 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/platform/basic.h"
+
+#include "mongo/scripting/jsexception.h"
+
+#include "mongo/base/init.h"
+#include "mongo/bson/bsonobjbuilder.h"
+
+namespace mongo {
+namespace {
+
+constexpr auto kCodeFieldName = "code"_sd;
+constexpr auto kCodeNameFieldName = "codeName"_sd;
+constexpr auto kOriginalErrorFieldName = "originalError"_sd;
+constexpr auto kReasonFieldName = "errmsg"_sd;
+constexpr auto kStackFieldName = "stack"_sd;
+
+}  // namespace
+
+void JSExceptionInfo::serialize(BSONObjBuilder* builder) const {
+    builder->append(kStackFieldName, this->stack);
+
+    {
+        BSONObjBuilder originalErrorBuilder(builder->subobjStart(kOriginalErrorFieldName));
+        originalErrorBuilder.append(kReasonFieldName, this->originalError.reason());
+        originalErrorBuilder.append(kCodeFieldName, this->originalError.code());
+        originalErrorBuilder.append(kCodeNameFieldName,
+                                    ErrorCodes::errorString(this->originalError.code()));
+        if (auto extraInfo = this->originalError.extraInfo()) {
+            extraInfo->serialize(&originalErrorBuilder);
+        }
+    }
+}
+
+std::shared_ptr<const ErrorExtraInfo> JSExceptionInfo::parse(const BSONObj& obj) {
+    auto stack = obj[kStackFieldName].String();
+
+    auto originalErrorObj = obj[kOriginalErrorFieldName].Obj();
+    auto code = originalErrorObj[kCodeFieldName].Int();
+    auto reason = originalErrorObj[kReasonFieldName].checkAndGetStringData();
+    Status status(ErrorCodes::Error(code), reason, originalErrorObj);
+
+    return std::make_shared<JSExceptionInfo>(std::move(stack), std::move(status));
+}
+
+MONGO_INIT_REGISTER_ERROR_EXTRA_INFO(JSExceptionInfo);
+
+}  // namespace mongo