Allow multiple proxies for dev server.

[hayleigh-dot-dev]

Currently, users can configure an api proxy for the development server by adding the following to their gleam.toml:

[tools.lustre.dev]
proxy = { from = "/api", to = "http://localhost:3000/api" }

It's not uncommon to want to configure multiple proxies, for example to serve additional static assets from a separate server app. We should support both single object proxy configuration and array of objects!

[chuckberrypi]

I ran into a situation where I have a couple different entry points in my back end I wanted to proxy to, so this is something I'd be interested in taking a stab at.

I noticed that in dev.gleam builds the proxy by calling functions from the cli module

use proxy_from <- cli.string("", ["dev", "proxy", "from"], project, "")
use proxy_to <- cli.string("", ["dev", "proxy", "to"], project, "")

Since they're called with empty strings, the cli function will always get the values from the TOML file. Is there a plan to add flags for passing in proxy info, or can this be simplified by just deriving the proxies from the project.options directly in the start function?

Also, since proxy will become a list, it seems to me that we could do away with the None variant and just pass an empty [] when there are no proxies.

[hayleigh-dot-dev]

Is there a plan to add flags for passing in proxy info

No plans I think

Can this be simplified by just deriving the proxies from the project.options directly in the start function?

But I think it's valuable if all the project config goes through the same interface.

Also, since proxy will become a list, it seems to me that we could do away with the None variant and just pass an empty [] when there are no proxies.

That sounds likely yeah.