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Issue scope

Library (crate)

Describe the bug

When serving pre-compressed files using zstd, the Content-Encoding header is set to "zst" instead of the correct "zstd". This causes browsers and other clients to fail to handle the content properly.

How to reproduce it

1. Start the static-web-server with compression-static enabled and with zstd compressed files. e.g.

echo "Test Content" > index.html
zstd index.html
docker run -p 8080:80 -v "$(pwd):/public" joseluisq/static-web-server:2-debian@sha256:8208279b906b8382d616162a8ba04eda00e4b978fac368c282dfb4cb1bfec136  --compression-static=true

2. Access the server with Accept-Encoding set to zstd, and observe that the Content-Encoding is returned as "zst".

$ curl 127.0.0.1:8080 -v -H "Accept-Encoding: zstd" --compressed 
*   Trying 127.0.0.1:8080...
* Connected to 127.0.0.1 (127.0.0.1) port 8080 (#0)
> GET / HTTP/1.1
> Host: 127.0.0.1:8080
> User-Agent: curl/7.81.0
> Accept: */*
> Accept-Encoding: zstd
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< last-modified: Wed, 29 May 2024 02:46:36 GMT
< content-type: text/html
< accept-ranges: bytes
< content-encoding: zst
< vary: accept-encoding
< cache-control: public, max-age=86400
< transfer-encoding: chunked
< date: Wed, 29 May 2024 02:46:45 GMT
<
curl: (61) Unrecognized content encoding type. libcurl understands deflate, gzip, br, zstd content encodings.

Expected behavior

The Content-Encoding header should be "zstd".

Complementary information

No response

Build target

Docker linux/amd64

Environment and specs

• static-web-server: v2.31.1
• Rust: v1.78.0
• OS: Docker on Ubuntu 22.04
• Arch: x86_64 (64-bit)
• Docker: 26.1.3-1
• Client: curl

Additional context

This behavior is caused by the precompressed_variant function in src/compression_static.rs.