Websocket after send(data) disconnects

[mcrooks83]

In companion 

//set up a socket to send data
import * as messaging from "messaging";

//fetch user data first

const wsUri = "ws://127.0.0.1:8080" 
console.log("creating websocket")
var websocket = new WebSocket(wsUri);
websocket.addEventListener("open", onOpen);
//websocket.addEventListener("close", onClose);
websocket.addEventListener("message", onMessage);
websocket.addEventListener("error", onError);

function onOpen(evt) {
    console.log("CONNECTED");
 }
 
 function onClose(evt) {
    console.log("DISCONNECTED");
 }
 
 function onMessage(evt) {
    console.log(`MESSAGE: ${evt.data}`);
 }
 
 function onError(evt) {
    console.error(`ERROR: ${evt.data}`);
 }


//open socket to fitbit device
messaging.peerSocket.addEventListener("open", (evt) => {
  console.log("Ready to send or receive messages");

});

messaging.peerSocket.addEventListener("message", (evt) => {
    //post data to our kafka consumer
    console.log(JSON.stringify(evt.data));
    const data = JSON.stringify(evt.data)
    websocket.send(data)

});

as soon as data is received and sent the socket disconnects. 

[4:37:23 PM] Companion: Ready to send or receive messages                                                                   (companion/index.js:33,3)
[4:37:23 PM] Companion: CONNECTED                                                                                           (companion/index.js:15,5)
[4:37:27 PM] Companion: {"hr":166,"timestamp":2429038522}                                                                   (companion/index.js:39,5)
[4:37:27 PM] Companion: DISCONNECTED  

is there something I need to do to prevent this disconnection?

Thanks in advance! 

[mcrooks83 · Accepted solution]

ok, I solved this and its nothing to do with FitBit SDK!  It was dependent on how you implement the websocket server.   Here is a simple websocket server that works.  

from simple_websocket_server import WebSocketServer, WebSocket

class SimpleEcho(WebSocket):
    def handle(self):
        # echo message back to client
        print(self.data)
        #self.send_message(self.data)

    def connected(self):
        print(self.address, 'connected')

    def handle_close(self):
        print(self.address, 'closed')


server = WebSocketServer('', 8080, SimpleEcho)
server.serve_forever()

[mcrooks83]

this can be dockerised with

FROM python:3.8-slim

# App setup
COPY . /app
WORKDIR /app
RUN pip install --upgrade pip
RUN pip install simple-websocket-server

EXPOSE <your_port>

CMD ["python", "-u", "<your_sever>.py"]

 but update this line in the socket server

server = WebSocketServer('0.0.0.0', 8080, SimpleEcho)

 to run it locally.