A small Kotlin client for phoenix channel

Great work. I have managed to incorporate it inside my otherwise Java written Android application. I am calling the socket connection from inside a Service. There was an issue of joining channels multiple times and issues of failure to reconnect after internet connection loss. I have resolved those issues by this:

PhxSocket.java

public class PhxSocket extends Service {

    GoSocket goSocket;
    Socket socket;
    Socket.Options socketOptions;

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    private void init_goSocket() {

        goSocket = null;

        try {
            socket.disconnect(null, null, null);
        } catch (Exception ignored) {
        }

        goSocket = new GoSocket();
        socketOptions = new Socket.Options();
        socketOptions.setHeartbeatIntervalMs(5_000);
        HashMap<String, Object> hashMap = new HashMap<String, Object>();
        hashMap.put("uuid", MainActivity._uuid());
        socketOptions.setParams(hashMap);
        socket = new Socket("https://my.app.com/socket", socketOptions);
        goSocket.initialize(MainActivity._uuid(), socket);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        if (socket == null || socket.isConnected() == false) {
            init_goSocket();
        }

        return Service.START_NOT_STICKY;
    }
}

GoSocket.kt

class GoSocket {

    fun initialize(uuid: String, sd: Socket) {

        sd.connect()

        val clientChannel = sd.channel("client:$uuid")

        clientChannel
                .join()
                .receive("ok") { msg ->
                
                }
                .receive("error") { msg ->
                
                }
                .receive("timeout") { msg ->
               
                }

        clientChannel.on("message:vc_notify") { msg ->
            println("Got a message: " + msg.response.toString())
            Intent().also { intent ->
                intent.action = "main-activity-broadcaster"
                intent.putExtra("main_activity_message", "vc_notify")
                LocalBroadcastManager.getInstance(MyApplication.getAppContext()).sendBroadcast(intent)
            }

        }

        clientChannel.on("message:vc") { msg ->
            println("Got a message: " + msg.response.toString())
            Intent().also { intent ->
                intent.action = "main-activity-broadcaster"
                intent.putExtra("main_activity_json", msg.response.toString())
                LocalBroadcastManager.getInstance(MyApplication.getAppContext()).sendBroadcast(intent)
            }

        }

        val connectedChannel = sd.channel("clients:connected")

        connectedChannel
                .join()
                .receive("ok") { msg ->
               
                }
                .receive("error") { msg ->
             
                }
                .receive("timeout") { msg ->
                   
                }
    }
}

I am not sure if there is a better way to do it. If so, kindly tell me.

I ported the JS code logic to kotlin, but the underlying websocket implementation has a bit different behavior compared to the browser web socket (in how lifecycle events are emited).

What I ended doing is when there is an error (not a regular error response from the server), I throw away both the channel and the socket (I call leave on channel and disconnect on socket and create new ones).

I didn’t have time to pinpoint the issue and patch my library.

As for your code, I see nothing wrong with it.

I have omitted some part above. Actually, I have wrapped the following within a fixed scheduler task running every 15 seconds:

        if (socket == null || socket.isConnected() == false) {
            init_goSocket();
        }

Thanks for the great work.