Channel messages - STMLink Docs

SRTC provides an IM channel (out-of-channel messaging) for things like pre-call ringing and notifications.

Enable

// IM session ID
let imSid = "";
let enableIm = async () => {
    // Call your backend API to get the IM enable token
    // api.getImToken
  
    let token = "IM enable token returned by your backend";
    imSid = await srtc.enableIm(token);
}

Receive IM messages

srtc.onNotifyImEvent = (evt: ImEvent) => {
    console.log('Received IM event', evt);
    switch (evt.type) {
        case ImEventType.IM_MSG:
            // Received an IM message
            // evt.data as ImMsgData
            break;
        
    }
}

Send IM messages

All IM messages must be sent through your backend API, so you can apply your own logic, such as sensitive-word filtering

// Call your backend API to send the IM message
// api.sendImMsg

Reconnecting / reconnected

When the network fluctuates, a reconnecting event fires; once reconnection succeeds, a reconnected event fires

// Inside onNotifyImEvent
case ImEventType.RECONNECTING:
  // Reconnecting started
  break;
case ImEventType.RECONNECTED:
  // Reconnected successfully
  break;

Disable / disconnect

Disconnection is either an active disable or a passive disconnect (when an unrecoverable error occurs)

// Active disable
await srtc.disableIm();
// Refresh and clean up the UI



// Passive disconnect
// Inside onNotifyImEvent
case ImEventType.DISCONNECTED:
  let data = (evt.data as ImDisconnectEventData);
  // You can show why IM disconnected based on reason
  alert('IM disconnected reason:' + data.reason);
  // Refresh and clean up the UI
  imSid = "";
  break;