Run zstd before brotli if both are enabled

[kamermans]

Since Safari doesn't support zstd yet, I have to keep brotli enabled, however, this module is run after brotli, so if both are supported, brotli is used. This is a problem since all browsers that support zstd also support brotli, so zstd is never actually used.

This PR reorders the module/filter before brotli so it takes priority (since it's faster and the compression is better).

I took this patch from #40 by @mklooss (thanks!)

[SuperSandro2000]

Is this a duplicate of #31?

Or this is a bug fix for f4ba115 ?

[mklooss]

@SuperSandro2000 you need this patch when u want brotli and zstd running at the same time.
The Filters Running fine, but "static" Files does not work properly.
Bcz Brotli always wins.

[n-rodriguez]

Hi there! Any news?

[MarcoMarcoaldi]

Hi, last day i try to compile NGINX 1.29.1 with OpenSSL 3.5.2 and zstd-nginx-module, anyway sometimes NGINX respond using br compression instead zstd. I cannot understand why.

When i test with command line curl like this :

curl -sS --http2 -D - -o /dev/null -H 'Accept-Encoding: zstd, br, gzip' https://www.inventivashop.com | tr -d '\r' | grep -iE 'HTTP/|content-encoding|alt-svc|server'

Response :

HTTP/2 200
server: nginx
x-hosting-by: managedserver.it - Performance Managed Hosting
alt-svc: h3=":443"; ma=86400, h3-29=":443"; ma=86400
content-encoding: zstd

NGINX respond correctly using ALWAY zstd. When i use Chrome the 90% of test response in BR compression. I cannot understand why.