Websocket connections no longer work

[Artur-]

Bug description

A Vaadin application in development uses a websocket connection to provide live reload capabilities. The live reload server listens to port 35729, which is indicated in the lower right corner in the Gitpod UI: Ports: 33411, 35729, 3799, 8080, 45049.

Port 35729 should be mapped to e.g.

$ gp url 35729
https://35729-jade-turkey-nd11myav.ws-eu03.gitpod.io

However, establishing a connection to wss://35729-jade-turkey-nd11myav.ws-eu03.gitpod.io/ fails without any other information in the browser console than WebSocket connection to 'wss://35729-jade-turkey-nd11myav.ws-eu03.gitpod.io/' failed.

An additional note is that a websocket connection is also established to wss://8080-jade-turkey-nd11myav.ws-eu03.gitpod.io/vaadinServlet/?v-r=push&refresh_connection and this one works properly

Steps to reproduce

1. Open http://gitpod.io/#https://github.com/vaadin/skeleton-starter-flow-spring
2. Wait for the app to be shown (a text field and a button)

Expected behavior

The dev mode indicator in the lower right corner has a full green circle, not a half red half green.

The browser console has no errors

Example repository

https://github.com/vaadin/skeleton-starter-flow-spring

Anything else?

This has worked before

[akosyakov]

It is reproducible only in VS Code right? not in Theia? Hm, nope probably in both.

[Artur-]

Same problem with Theia

[yyoncho]

I am having the same issue when trying to display gtk apps via Broadway

[yyoncho]

Just want to mention that in some cases websockets work fine. I have a demo using https://github.com/xtermjs/xterm.js/ with powered by websocket connection and it works fine. On the other side, gdk broadway does not work. You could reproduce it sing gitpod/workspace-full - type broadwayd :5 which will open port 8085 then in the browser console you will see an error for unable to connect.

[svenefftinge]

Can you share an example repo with gdk/broadway?
Sorry got it, it is installed with workspace-full. thanks

[svenefftinge]

Although I was able to reproduce both cases I couldn't figure out what causes the issue. Seems like ws-proxy has issues with the websocket server's response as it logs.

"could not connect to backend /: EOF"

And the returns 404.