Pass connectionState to onDisconnect()

cheatsheet.md

@@ -62,7 +62,8 @@ io.onConnection(channel => {
   const { id } = channel
 
   // whenever the channel got disconnected
-  channel.onDisconnect(() => {})
+  // the event will be 'disconnected', 'failed' or 'closed'
+  channel.onDisconnect(event => {})
 
   // listen for a custom event
   channel.on('chat message', data => {})

packages/chatApp/src/server.ts

@@ -29,8 +29,9 @@ server.listen(3000, () => {
 })
 
 io.onConnection((channel: ServerChannel) => {
-  channel.onDisconnect(() => {
-    console.log(`${channel.id} got disconnected`)
+  channel.onDisconnect(event => {
+    console.log('onDisconnect event:', event)
+    if (event === 'closed') console.log(`The connection for channel ${channel.id} got closed!`)
   })
 
   channel.emit('chat message', `Welcome to the chat ${channel.id}!`)

packages/common/src/typings.ts

@@ -60,6 +60,10 @@ export interface ConnectionEventCallbackServer {
   (channel: any): void
 }
 
+export interface DisconnectEventCallbackServer {
+  (connectionState: 'disconnected' | 'failed' | 'closed'): void
+}
+
 export interface EventOptions {
   roomId?: RoomId
   senderId?: ChannelId

packages/server/src/wrtc/channel.ts

@@ -10,7 +10,7 @@ import {
   RawMessage,
   ChannelId,
   EventName,
-  ConnectionEventCallbackServer,
+  DisconnectEventCallbackServer,
   EventCallbackRawMessage,
   ServerOptions,
   EmitOptions
@@ -72,12 +72,13 @@ export default class ServerChannel {
 
   /**
    * Listen for the disconnect event.
-   * @param callback The event callback.
+   * Gets the connectionState 'disconnected', 'failed' or 'closed'. See https://developer.mozilla.org/en-US/docs/Web/API/RTCPeerConnection/connectionState
+   * @param callback The connectionState.
    */
-  onDisconnect(callback: ConnectionEventCallbackServer) {
-    this.eventEmitter.on(EVENTS.DISCONNECT, (channel: ServerChannel) => {
-      let cb: ConnectionEventCallbackServer = channel => callback(channel)
-      cb(channel)
+  onDisconnect(callback: DisconnectEventCallbackServer) {
+    this.eventEmitter.on(EVENTS.DISCONNECT, (connectionState: 'disconnected' | 'failed' | 'closed') => {
+      let cb: DisconnectEventCallbackServer = connectionState => callback(connectionState)
+      cb(connectionState)
     })
   }
 

packages/server/src/wrtc/connectionsManager.ts

@@ -32,7 +32,7 @@ export default class ConnectionsManagerServer {
 
     pc.onconnectionstatechange = () => {
       if (pc.connectionState === 'disconnected' || pc.connectionState === 'failed' || pc.connectionState === 'closed') {
-        connection.channel.eventEmitter.emit(EVENTS.DISCONNECT)
+        connection.channel.eventEmitter.emit(EVENTS.DISCONNECT, pc.connectionState)
         this.deleteConnection(connection)
       }
     }