Open web UI on appdaemon breaks when accessing remotely

[Ten0]

Problem/Motivation

Clicking "Open WEB UI" when connected remotely does not work: it tries to open http://<my-url>:5050/ but when connected remotely (DDNS and exposed HA on HTTPS), I don't necessarily have that NAT-ed.
In fact, I don't want to NAT this, because there's no authentication on there so it clearly can't be opened to outside.

There is demand for this to work: https://community.home-assistant.io/t/solved-unable-to-connect-to-web-ui/134193/6

Proposed changes

My understanding is that HomeAssistant has a feature called "Ingress" that enables exposing the web UI as an iframe within Home Assistant:

• https://github.com/hassio-addons/addon-ssh/blob/d7c4c89b3c5f9c5948dae022041b006424e57250/ssh/config.yaml#L9-L11
• https://www.home-assistant.io/blog/2019/04/15/hassio-ingress/

Then one should bind to the ingress port instead of to a fully exposed port, and it would:

1. work
2. be more secure (because it would now be authenticated by HomeAssistant instead of being exposed without authentication on the local network)

[frenck]

This app cannot work via Ingress.

If you want to expose it to the outside world, you'd have to do that yourself.

../Frenck

[Ten0]

Thanks for your answer. Would you have a second to elaborate on why the UI can't work via ingress, for future reference? Thanks.

[frenck]

It doesn't let itself being served that way.

[Ten0]

It doesn't let itself being served that way.

I still don't understand what specifically would prevent it from working if we were to just set the parameters and bind to the correct port. Can you please point out what in the below reasoning is incorrect?
Thanks.

1. The way ingress works is it sets a port that the container should expose its http server on somewhere (in an env var?) and then the server should bind there and ingress forwards HTTP & websocket requests to that port provided proper authentication.
2. Currently appdaemon binds an HTTP server on a particular port (5050) that is globally exposed. We can update that to make it bind its HTTP server to the parameter provided by HA's ingress system.
3. That's all we have to do for it to work. Ingress is able to forward both HTTP & Websocket and that's all appdaemon needs for that web UI to work.

[sinclairpaul]

The application needs to support being served from a path, i.e. /somefolder/mypath. This can be a challenge for apps which assume everything is served from root (i.e. Javascript/asset loads etc)

[Ten0]

Thanks!
For reference: now tracked at AppDaemon/appdaemon#2175