Socket connection from browser to custom microservice through webapp-starter

[akshayeshenoi]

Hi!
Is it currently possible to reverse-proxy WebSocket connections initiated by the browser to a custom microservice? The lack of it requires the front-end to connect to the microservice directly which entails authentication woes.

[gstroup]

No, currently the webapp-starter does not support proxying websocket connections. It's a good idea, and something we've considered. For now, you could look at the predix-toolkit code for an example of proxying web socket connections.
https://github.com/PredixDev/predix-tool-kit/blob/master/server/security-app.js

Also, this npm package is very popular, and supports web socket proxying:
https://github.com/nodejitsu/node-http-proxy

[akshayeshenoi]

Would you be willing to accept a PR?

[gstroup]

Yes, I think a PR would be useful. How are you planning to implement it?

[akshayeshenoi]

Kind of like how it's implemented in the predix-toolkit example code you shared.

• A websocket server will be instantiated on the webapp-starter.
• Clients will hit a certain endpoint to connect to the websocket on another microservice.
• A new ws connection to the microservice will be established by the webapp-starter (acting as a client), and a new socketID will be generated for it which will be returned to the client. The new socket created will be stored in-memory against the ID.
• The client will then connect to the websocket we instantiated before and send the ID within the body of the message. The webapp-starter will use that ID to fetch the socket and forward the message.

All communication will depend upon this socketID. Sounds good?

[gstroup]

Sounds good. Let's try to keep most of this logic in a separate file in the /server directory. Thanks for the initiative.