expose delayed_leave_event_restart_local_timeout_ms to config.json (#3415)

src/config/ConfigOptions.ts

@@ -125,6 +125,17 @@ export interface ConfigOptions {
     /** @deprecated use delayed_leave_event_delay_ms instead */
     membership_server_side_expiry_timeout?: number;
 
+    /**
+     * The time (in milliseconds) after which a we consider a delayed event restart http request to have failed.
+     * Setting this to a lower value will result in more frequent retries but also a higher chance of failiour.
+     *
+     * In the presence of network packet loss (hurting TCP connections), the custom delayedEventRestartLocalTimeoutMs
+     * helps by keeping more delayed event reset candidates in flight,
+     * improving the chances of a successful reset. (its is equivalent to the js-sdk `localTimeout` configuration,
+     * but only applies to calls to the `_unstable_updateDelayedEvent` endpoint with a body of `{action:"restart"}`.)
+     */
+    delayed_leave_event_restart_local_timeout_ms?: number;
+
     /**
      * The time interval (in milliseconds) at which the client sends membership keep-alive
      * messages to the server by restarting the timer for the delayed leave event.

src/rtcSessionHelpers.ts

@@ -128,6 +128,8 @@ export async function enterRTCSession(
       delayedLeaveEventDelayMs:
         matrixRtcSessionConfig?.delayed_leave_event_delay_ms ??
         matrixRtcSessionConfig?.membership_server_side_expiry_timeout,
+      delayedLeaveEventRestartLocalTimeoutMs:
+        matrixRtcSessionConfig?.delayed_leave_event_restart_local_timeout_ms,
       networkErrorRetryMs: matrixRtcSessionConfig?.network_error_retry_ms,
       makeKeyDelay:
         matrixRtcSessionConfig?.wait_for_key_rotation_ms ??