Skip to content

compression-vary: Enhanced Vary header handling for compression

Debian/Ubuntu installation

These docs apply to the APT package nginx-module-compression-vary provided by the GetPageSpeed Extras repository.

  1. Configure the APT repository as described in APT repository setup.
  2. Install the module:
sudo apt-get update
sudo apt-get install nginx-module-compression-vary
Show suites and architectures 
| Distro   | Suite             | Component   | Architectures   |
|----------|-------------------|-------------|-----------------|
| debian   | bookworm          | main        | amd64, arm64    |
| debian   | bookworm-mainline | main        | amd64, arm64    |
| debian   | trixie            | main        | amd64, arm64    |
| debian   | trixie-mainline   | main        | amd64, arm64    |
| ubuntu   | focal             | main        | amd64, arm64    |
| ubuntu   | focal-mainline    | main        | amd64, arm64    |
| ubuntu   | jammy             | main        | amd64, arm64    |
| ubuntu   | jammy-mainline    | main        | amd64, arm64    |
| ubuntu   | noble             | main        | amd64, arm64    |
| ubuntu   | noble-mainline    | main        | amd64, arm64    |

Name

ngx_http_compression_vary_filter_module is a header filter module used instead of the 'gzip_vary' directive.

Table of Content

Status

This Nginx module is currently considered experimental. Issues and PRs are welcome if you encounter any problems.

Synopsis

server {
    listen 127.0.0.1:8080;
    server_name localhost;

    location / {
        gzip on;
        compression_vary on;

        proxy_pass http://foo.com;
    }
}

Directives

compression_vary

Syntax: compression_vary on | off;

Default: compression_vary off;

Context: http, server, location

Enables or disables inserting the Vary: Accept-Encoding response header field if the directives gzip, gzip_static, or gunzip are active.

Unlike gzip_vary, if a Vary header exists for the original response, it will append the Accept-Encoding to the original Vary header. In addition, multiple Vary headers will be merged into one and separated by commas. Duplicate header values ​​in Vary will be removed.

This module is also effective when the directives from third-party compression modules such as brotli, brotli_static, unbrotli, zstd, zstd_static, and unzstd are activated.