websocket port is hard coded about erlangpl

[baransu]

Thank for spotting this!
Good solution would be to create some endpoint providing config for UI and then creating WebSocket connection based on that.

[arkgil]

I think that sufficient solution would be to allow users to enter hostname and port number to connect to from UI (which would defualt to localhost:8000 of course). If someone wants to change port number we serve content on, if think they would be fine configuring it in UI. What would you think about that @dgulinobw?

[dgulinobw]

An automated way would be cool, but anything that doesn't involve rebuilding would be sufficient.

[michalslaski]

In the old UI we injected WebSocket port number read from the command line argument into the HTML/JS templates before serving them from cowboy to browsers. Is the same possible after React is built, e.g. can we regexp on "8000" and change it to custom port number?

[baransu]

Probably yes but it's far from being elegant. And we have also Elm code which can look for port number, we could pass it from React via ports but I don't know. I would go with config endpoint with:

• port number
• current version

[michalslaski]

@dgulinobw is port 8000 conflicting with some service, which is running on many operating systems?

The original intention behind having -P flag was to allow users, who have port 8000 occupied by other processes in the system, to decide which port is most suitable for their setup. I can see two options:

• use port 37575 instead of 8000, hard code it in cowboy/JS/Elm, remove -P flag
• keep the -P flag, let JS/Elm open WebSocket on the same port as the one found in the URL, from which the UI assets were served - @baransu is that possible?

[baransu]

I would keep -P flag.

No problem with that. So in production when assets are served by server it will look for port in url and for development it will look for default 8000 when UI is standalone.

[michalslaski]

It seems the port 8000 is a default one for many popular applications like WinAmp and trojans. Maybe it makes sense to have the development port set to 37575.

BTW, try typing on the classic phone with T9 the word "erlpl".

[baransu]

So let switch to 37575 by default keeping -P flag.