HTTP GZIP compression

You can configure GZIP compression in Release. GZIP compression is used to decrease the size of server responses and save bandwidth usage. There is a small overhead of server CPU usage to compress content. It is enabled by default, but you may want to adjust the settings depending on your use case.

If you have a fast network, or if there is an HTTP server in front of Release which already performs GZIP compression, you can disable it by setting enabled: false in the configuration, see table below.

Configuring the GZIP compression settings

To configure the GZIP settings:

  1. Add the xl, server and http properties to the XL_RELEASE_SERVER_HOME/conf/xl-release.conf configuration file.

  2. In the http property, add an additional gzip property. This property identifies the predefined GZIP configuration you wish to use. The supported values are:

    Parameter Description
    enabled Whether to enable GZIP Compression. Default is true.
    minSize Content over this size will be compressed. In bytes or HOCON format. Default is 10 kB.
    compression Compression level from 0-9. Default is 4.
    excludedPaths List of string paths that will be excluded from the compression.

Sample GZIP compression settings

xl {
    server {
        http {
            gzip {
                enabled: true
                minSize: 10 kB
                compression: 4
                excludedPaths: []
            }
        }
    }
}

Disabling GZIP compression on the client side

GZIP is supported by default on most modern browsers. GZIP compression will only be used if the HTTP request’s Accept-Encoding header contains the value gzip.