SERVER-18288 implement a common interface for OP_COMMAND and OP_QUERY

1 files changed, 76 insertions, 0 deletions

diff --git a/src/mongo/rpc/reply_interface.h b/src/mongo/rpc/reply_interface.h
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+++ b/src/mongo/rpc/reply_interface.h
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+/**
+ *    Copyright (C) 2015 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.
+ */
+
+#pragma once
+
+#include "mongo/base/disallow_copying.h"
+
+namespace mongo {
+    class BSONObj;
+    class Message;
+
+namespace rpc {
+    class DocumentRange;
+
+    /**
+     * An immutable view of an RPC Reply.
+     */
+    class ReplyInterface {
+        MONGO_DISALLOW_COPYING(ReplyInterface);
+    public:
+        virtual ~ReplyInterface() = default;
+
+        /**
+         * Accessor for the metadata object. Metadata is generally used for information
+         * that is independent of any specific command, e.g. auditing information.
+         */
+        virtual const BSONObj& getMetadata() const = 0;
+
+        /**
+         * The result of executing the command.
+         */
+        virtual const BSONObj& getCommandReply() const = 0;
+
+        /**
+         * A variable number of BSON documents returned by the command. It is valid for the
+         * returned range to be empty.
+         *
+         * Example usage:
+         *
+         * for (auto&& doc : reply.getOutputDocs()) {
+         *    ... do stuff with doc
+         * }
+         */
+        virtual DocumentRange getOutputDocs() const = 0;
+
+    protected:
+        ReplyInterface() = default;
+    };
+
+}  // namespace rpc
+}  // namespace mongo