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diff --git a/src/mongo/client/sdam/topology_listener.h b/src/mongo/client/sdam/topology_listener.h
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+/**
+ *    Copyright (C) 2020-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.
+ */
+
+#pragma once
+
+#include "mongo/client/sdam/sdam_datatypes.h"
+#include "mongo/util/uuid.h"
+
+namespace mongo::sdam {
+
+/**
+ * An interface for handling topology related events.
+ */
+class TopologyListener {
+public:
+    /**
+     * Called when a TopologyDescriptionChangedEvent is published - The TopologyDescription changed
+     * and the new TopologyDescription does not match the old.
+     */
+    void onTopologyDescriptionChangedEvent(UUID topologyId,
+                                           TopologyDescriptionPtr previousDescription,
+                                           TopologyDescriptionPtr newDescription){};
+
+    /**
+     * Called when a ServerHeartBeatSucceededEvent is published - A heartbeat sent to the server at
+     * hostAndPort succeeded. durationMS is the execution time of the event, including the time it
+     * took to send the message and recieve the reply from the server.
+     */
+    void onServerHeartbeatSucceededEvent(mongo::Milliseconds durationMs,
+                                         ServerAddress hostAndPort){};
+
+    /*
+     * Called when a ServerPingFailedEvent is published - A monitoring ping to the server at
+     * hostAndPort was not successful.
+     */
+    void onServerPingFailedEvent(const ServerAddress hostAndPort, const Status& status){};
+
+    /**
+     * Called when a ServerPingSucceededEvent is published - A monitoring ping to the server at
+     * hostAndPort was successful. durationMS is the measured RTT (Round Trip Time).
+     */
+    void onServerPingSucceededEvent(mongo::Milliseconds durationMS, ServerAddress hostAndPort){};
+};
+
+}  // namespace mongo::sdam