blog/source/_posts/caddy2-pre-compressed.md

245 lines
5.4 KiB
Markdown
Raw Normal View History

---
title: Serving pre-compressed files in Caddy 2
excerpt: gzip and brotli files
date: 2020-11-12
tags:
- caddy
---
Caddy v0.9.4+ and v1.0.0+ support pre-compressed gzip and brotli files automatically. However, this feature is [not yet](https://github.com/caddyserver/caddy/issues/2665) implemented in v2 and requires manual configuration. Examples available at the Caddy forum are incomplete, it's either gzip or brotli. The config provided in this guide supports _both_, prioritising brotli if supported by the requesting web browser (and there are .br files), otherwise fallback to gzip.
## Default usage
This configuration supports URL normalisation; when a URL has a trailing slash `http://localhost:8080/about/`, Caddy will serve `http://localhost:8080/about/index.html` using _internal/transparent_ redirect (without 301/302 redirect). If you need to internal redirect `http://localhost:8080/bio` to `http://localhost:8080/bio.html`, refer to the [next section](#Pretty-URLs).
``` plain Caddyfile
http://localhost:8080 {
bind 127.0.0.1 ::1
root * /home/user/www
file_server
@brotli {
header Accept-Encoding *br*
file {
try_files {path}.br {path}/index.html.br
}
}
handle @brotli {
header Content-Encoding br
rewrite {http.matchers.file.relative}
}
@gzip {
header Accept-Encoding *gzip*
file {
try_files {path}.gz {path}/index.html.gz
}
}
handle @gzip {
header Content-Encoding gzip
rewrite {http.matchers.file.relative}
}
@html {
file
path *.html */
}
header @html Content-Type text/html
@css {
file
path *.css
}
header @css Content-Type text/css
@js {
file
path *.js
}
header @js Content-Type text/javascript
@svg {
file
path *.svg
}
header @svg Content-Type image/svg+xml
@xml {
file
path *.xml
}
header @xml Content-Type application/xmlr
}
@json {
file
path *.json
}
header @json Content-Type application/json
}
```
### Content-Type
```
@svg {
file
path *.svg
}
header @svg Content-Type image/svg+xml
```
`Content-Type` response header needs to be specified as a workaround, otherwise Caddy responds with `application/gzip`.
### URL normalisation
```
@html {
file
path *.html */
}
```
`*/` is to match path with a trailing slash `/path/` since that is (transparently) redirects to `/path/index.html`.
### Dummy files
```
root * /home/user/www
```
I prepared a set of dummy files with most common file extensions ([download](/files/20201112/dummy.zip)). This enables you to test whether Caddy serves the correct file. `.gz` and `.br` files are _not_ compressed files, they are text files so that you can easily identify the file being served. This also means you cannot test it on browsers since the files are not gzip/brotli-compressed files (you'll get encoding error); also note that web browsers only send `Accept-Encoding: br` request header to HTTPS website.
Unzip the dummy.zip and specify the folder in the `root` directive. Following are some sample tests after you start Caddy:
```
$ curl -i http://localhost:8080/foo.svg -H 'Accept-Encoding: gzip'
# /foo.svg.gz should be served
HTTP/1.1 200 OK
Content-Encoding: gzip
Content-Type: image/svg+xml
svg gz
```
```
$ curl -i http://localhost:8080/foo.svg -H 'Accept-Encoding: gzip,br'
# /foo.svg.br should be served
HTTP/1.1 200 OK
Content-Encoding: br
Content-Type: image/svg+xml
svg br
```
```
$ curl -i http://localhost:8080/foo.svg
# /foo.svg should be served
HTTP/1.1 200 OK
Content-Type: image/svg+xml
svg
```
## Pretty URLs
This configuration supports transparently redirect a URL without trailing slash and file extension, e.g. `http://localhost:8080/bio` to `http://localhost:8080/bio.html`. If you request "bio.html", Caddy still still serve it as usual, without any redirect. This feature is similar to [Netlify's](https://docs.netlify.com/routing/redirects/redirect-options/#trailing-slash).
``` plain Caddyfile
http://localhost:8080 {
bind 127.0.0.1 ::1
root * /home/user/www
file_server
try_files {path}.html
@brotli {
header Accept-Encoding *br*
file {
try_files {path}.br {path}/index.html.br {path}.html.br
}
}
handle @brotli {
header {
Content-Encoding br
Content-Type text/html
}
rewrite {http.matchers.file.relative}
}
@gzip {
header Accept-Encoding *gzip*
file {
try_files {path}.gz {path}/index.html.gz {path}.html.gz
}
}
handle @gzip {
header {
Content-Encoding gzip
Content-Type text/html
}
rewrite {http.matchers.file.relative}
}
@html {
file
path *.html */
}
header @html {
Content-Type text/html
defer
}
@css {
file
path *.css
}
header @css {
Content-Type text/css
defer
}
@js {
file
path *.js
}
header @js {
Content-Type text/javascript
defer
}
@svg {
file
path *.svg
}
header @svg {
Content-Type image/svg+xml
defer
}
@xml {
file
path *.xml
}
header @xml {
Content-Type application/xml
defer
}
@json {
file
path *.json
}
header @json {
Content-Type application/json
defer
}
}
```
Derived from [[1]](https://caddy.community/t/how-to-serve-pre-compressed-files-with-caddy-v2/8760), [[2]](https://caddy.community/t/how-to-serve-gzipped-files-automatically-in-caddy-v2/7311), [[3]](https://caddy.community/t/why-caddy-2-is-not-able-to-serve-static-brotli-files/7653).