Support http auth for health checks

[HLFH]

It would be great to support two parameters:

• health-check-username
• health-check-password

Example of Docker app that needs HTTP auth: Transmission.
https://hub.docker.com/r/linuxserver/transmission

kamal-proxy deploy does not work when the root URL requires HTTP auth.

[zdehasek]

Yes, this feature would be really cool.
I’m currently deploing Prometheus using HTTP authentication, and it would be great if Kamal Proxy could handle this. Otherwise, I won’t be able to deploy it at all.

We don’t even need new parameters: HTTP auth could be set like this: user:password@example.org. So, if the proxy allows providing a full URL instead of just the path, that would be perfect.

I am not a go developer, but if PR like this will be merged, I am happy to do my best :)

[cavi21]

Hi, just joining the conversation in in order to know if there is interest to have this supported by kamal-proxy? maybe @kevinmcconnell, whenever you find the time, if can share your ideas or concerns about this it would be great :)!

[monorkin]

I'm curious, why would you want to protect the health check endpoint with basic auth?

[cavi21]

Some services that could be deployed as accessories with Kamal that has proxy config could have this requirement, for example elastic/elasticsearch, but there are others too, there is also a conversation (basecamp/kamal#1122) that touch this case

[cavi21]

Hi @monorkin did you had the chance to check this? maybe another option will be to be able to define the http status code to consider healthy, so maybe the 200 can be overridden with 403 for the example I shared