Add serve_file method to route

[mendelt]

This pr adds a serve_file method alongside the already existing serve_dir method.

[Fishrock123]

seems reasonable

[mendelt]

I added serve_file to Route to be consistent with how serve_dir works for now.
Personally I would like the Route struct to stay a bit cleaner. We could add specific helper methods like serve_dir and serve_file with extension traits, that way helper methods like this can be added to Route by importing the extension traits you need.
Does anyone have an opinion on this?

[goto-bus-stop]

I don't think an extension trait is necessary at this stage. There are only a few different methods on the trait, if you count the 10 HTTP method aliases as one 😜

[mendelt]

I don't think an extension trait is necessary at this stage. There are only a few different methods on the trait, if you count the 10 HTTP method aliases as one stuck_out_tongue_winking_eye

Funny you put it that way. Because in my fluent routes crate I put all of those aliases in their own extension trait too :-) https://github.com/mendelt/tide-fluent-routes/blob/c20244d6e2254f275ebc0ad46ebed2c621ef90a6/src/routebuilder.rs#L27

But for now this might be a bit premature, and I'd want to put serve_dir in an extension trait too. And that will break backward compatibiltiy. So yeah, this might be for later if there are more routing helper methods.

[yoshuawuyts]

Thanks so much for this PR @mendelt; this looks good!

In the past there's been talk about perhaps moving serve / serve_file into some sort of FileServer struct which would resemble much of how Tide's redirects work today. But we still need to finish up the design for that, and I don't think we should miss out on a chance to make serving single files easier until then.

Going to go ahead and merge this; thanks heaps!

[yoshuawuyts]

Tested this locally, and clippy + rustfmt pass. We need to update the CI, but in the interim I think this is fine to merge as-is. Thanks!