Websocket not working with socket.io in heroku

Question

My app is working fine in localhost with socket.io using websockets and xhr-polling and it's working with xhr-polling in heroku, but since heroku provided support for websocket I can ́t make it work using websockets.

My Chrome console shows this message:

WebSocket connection to 'ws://<myherokuapp>.herokuapp.com/socket.io/1/websocket/HBWE2BFvHahlSWk5ppHP' failed: Unexpected response code: 503

I already enabled websocket labs.

Is there any working example of websocket using socket.io?

Answer 1

I had the same problem and just fixed it by reactivating the websockets on my app on heroku. It had just randomly switched over to XHR polling for some reason.

I used this command from heroku's site (@ https://devcenter.heroku.com/articles/heroku-labs-websockets) to reactivate it:

heroku labs:enable websockets -a myapp

I then restarted my server by pushing to heroku and having it rebuild (or using: heroku restart).

I also have a working copy of a very basic socket.io chat application (written by Smitha Milli) running at: http://calm-gorge-8474.herokuapp.com/ that you can test.

Hope this helps!

• AmpT: I also found this answer, which also provides more clarity on how XHR polling could just randomly be activated, when randomly saved to cookies: stackoverflow.com/a/19680457/2728686
• gberger: "I then restarted my server by pushing to heroku and having it rebuild." You can restart by doing heroku restart
• Ashish Negi: @AmpT even your website calm is showing xhr-polling in my browser
• jmarceli: For use with simpleWebRTC I had to explicitly set port number 80 in url like so: http://myserver.herokuapp.com:80
• user1147171: "heroku labs:enable" was a good answer at the time, but it no longer works, nor is it necessary, since websockets is no longer a lab feature on Heroku, but is enabled by default.

Answer 2

you must use WebSocket connection to wss://<myherokuapp>.herokuapp.com/socket.io/1/websocket/HBWE2BFvHahlSWk5ppHP

wss:// not ws:// because Heroku is run on https protocol