Proxy to unix: socket

[eiszfuchs]

I'm currently writing a blog post as I try to replace nginx with Caddy step by step. My current setup is that I have a bunch of Python applications that I bind to unix: sockets* using gunicorn.
From what I understand, gunicorn isn't exactly FastCGI, so I had to use Caddy's proxy directive.

http://foobar.local {
    tls off
    proxy / unix:/var/www/flask/app.socket
}

This doesn't work as I would expect. I believe because it hasn't been implemented yet.
The socket file is owned by the same user Caddy is running under. Yet the only response I get is 502 Bad Gateway.

Am I missing something or is this hereby considered a feature request?

---

* I'm using sockets instead of ports because I hate having a spreadsheet with all the ports I use. Sockets are easier to organize.

[mholt]

Correct, unix sockets are only implemented for the fastcgi directive. Anyone is welcome to implement this for the proxy directive (I can't get around to it right now.)

[eiszfuchs]

Yay! Time to learn Go then! 👍

[mholt]

Sure :) This is how fastcgi does it: https://github.com/mholt/caddy/blob/47c5b6c9c40200cb7483bb890ac3a0e092771021/middleware/fastcgi/fastcgi.go#L126-L133

[eiszfuchs]

I'll give it a try. That doesn't look too complicated.

[eiszfuchs]

Status report

I've made some changes that seem to work.
You can review them here: https://github.com/mholt/caddy/compare/master...eiszfuchs:feature/proxy-socket?expand=1

Using this Caddyfile and running both added JavaScript files gives both responses, socket response and port response.

:2015

log access.log
errors error.log

proxy / localhost:59000 unix:/Users/eiszfuchs/proxy_test

I'm not sure if what I did is exactly what I should be doing, but strangely, it works, so I thought I might share my solution with you so we could talk about the changes I spent my whole day now on to work on the rough edges before I start working on _test.go files.
There's something that bugs me, I had to change parameter types of NewSingleHostReverseProxy because I needed to pass through the proper "host" name when creating a new net.Dial.

As I said, I'm fairly new to Go, though not to programming, and just for the record, I don't think I will use Go very often in the future. Go is so weird. 😊

[abiosoft]

Looks like we are not far off 👏

If you are gonna create a PR, you will need to remove the gitignore and js files from the commit and a rebase to single commit will be preferred.

Thanks 😊

[eiszfuchs]

Sure, I'll cleanup before submitting a PR! 👍
I'm not exactly comfortable with that at the moment, especially because my changes are calling url.Parse twice. I'll try to optimize that a bit.

The JavaScript files were meant for tests, the fastcgi middleware does include a PHP file, too.

[eiszfuchs]

Status report

I was able to refine my changes, clean everything up, remove the garbage and squash everything together: master...eiszfuchs:feature/proxy-socket
Turns out I could just use .String() to get what I needed, no need to change signatures here.

It's still lacking tests, because I've got no clue how to start writing these. :(

[mholt]

Nice, we can prove they work with some tests. You can do that with net.Listen and specify "unix" as the socket type.

Will probably need to take care that such tests do not fail to compile or run on Windows, as well.

Looking good so far!

[punkeel]

👍 <3

[eiszfuchs]

Then let's move the discussion to a proper Pull request, shall we?