brotli compression

[godofdream]

Many modern Browsers support brotli compression.
We should add optional brotli compression. It does not need to be best compressionlevel.

https://caniuse.com/#search=brotli

[Dexus]

Some information for this:
https://github.com/kothar/brotli-go (looks like it can used with streams as we need...)

[Dexus]

I have create a feature/brotli-compression branch, for those that would like implementation it. Please use this repo to push and/or create PRs

[Dexus]

I start to integrate brotli from https://github.com/google/brotli/tree/master/go/cbrotli
maybe it works as i hope :)

[Dexus]

any idea how to make it working without compile brotli as lib before?
Can we deliver precompiled pkg's?

[godofdream]

caddy has the same issue:
caddyserver/caddy#525

[Dexus]

okay, so we need to support brotli precompiled files or the users need to compile that them self.

[Allendar]

Wouldn't it be best to set the compression rate to the highest? Since the power of Brotli it's static system over Gzip's dynamic system. If a file get's compressed and never changes again it probably won't get a recompression. Brotli is much slower than Gzip, but if you Google the benchmarks you can easily get 15~25% more compression than on Gzip.

It kind of reminds me of doing this with Apache years ago under PHP, where you would pre-compress your assets with Grunt on Gzip level 9 and then purely serve the files compressed with the correct headers.

[Dexus]

For static files you are right, the best compression will be the best, but for dynamic contents it would be the best to use quality 0 to 5. speed vs compression.

Maybe we should also try to implement for static files check for gzip an br accept header and check files with gz or br suffix.