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diff --git a/src/mongo/s/multi_command_dispatch.h b/src/mongo/s/multi_command_dispatch.h
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+/**
+ *    Copyright (C) 2013 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/status.h"
+#include "mongo/base/string_data.h"
+#include "mongo/client/dbclientinterface.h"
+#include "mongo/s/bson_serializable.h"
+
+namespace mongo {
+
+    /**
+     * A MultiCommandDispatch is a send/recv operation for multiple commands at once.
+     *
+     * The commands are first registered with an endpoint and serializable request.  Commands are
+     * sent out without waiting for responses, and then responses are read later one-at-a-time.
+     *
+     * If context must be tracked alongside these requests, it can be associated with the endpoint
+     * object.
+     */
+    class MultiCommandDispatch {
+    public:
+
+        virtual ~MultiCommandDispatch() {
+        }
+
+        /**
+         * Adds a command to this multi-command dispatch.  Commands are registered with a
+         * ConnectionString endpoint and a serializable request.
+         *
+         * Commands are not sent immediately, they are sent on sendAll.
+         */
+        virtual void addCommand( const ConnectionString& endpoint,
+                                 const StringData& dbName,
+                                 const BSONSerializable& request ) = 0;
+
+        /**
+         * Sends all the commands in this dispatch to their endpoints, in undefined order and
+         * without waiting for responses.  May block on full send queue (though this should be
+         * rare).
+         *
+         * Any error which occurs during sendAll will be reported on recvAny, *does not throw.*
+         */
+        virtual void sendAll() = 0;
+
+        /**
+         * Returns the number of sent requests that are still waiting to be recv'd.
+         */
+        virtual int numPending() const = 0;
+
+        /**
+         * Blocks until a command response has come back.  Any outstanding command response may be
+         * returned with associated endpoint.
+         *
+         * Returns !OK on send/recv/parse failure, otherwise command-level errors are returned in
+         * the response object itself.
+         */
+        virtual Status recvAny( ConnectionString* endpoint, BSONSerializable* response ) = 0;
+    };
+
+}