feat(preview): allow setting compression options

[valadaptive]

Description

I noticed that the @polka/compression middleware doesn't compress WebAssembly files. While I intend to fix this upstream in @polka/compression itself, I think it's worth exposing the compression middleware options in Vite itself. I find the preview server useful for (roughly) profiling how long my application will take to load on slow connections, and hosts like GitHub Pages do compress WebAssembly.

I hope re-exporting the interface directly from @polka/compression isn't an issue--it seems to be done with the HTTP proxy options as well.

I can't seem to find the tests for the preview server--let me know what I should base the tests off of.

[bluwy]

We usually try to avoid adding new options to not make the config too complex. Is there a specific option you're looking to toggle that we could do by default instead?

[valadaptive]

If you'd prefer not to add compression options, you could just enable compressing WebAssembly files in the dev server (it may be worth going through and checking what has compressible: true in the mime-db package and making sure those are in the regex too)

[bluwy]

Yeah I think that's reasonable to add. Maybe also worth upstreaming this to @polka/compression like you mention, but I think we can also do this in vite directly first.

We're currently using mrmime which doesn't have compressible data to use, but perhaps a manual test/check with mime-db locally with the regex is enough here. I skim through mime-db and it seems like the regex already covers most.