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Version: 9.3.13.v20161014
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Gzip Handler

Gzip Rules
Gzip Configuration



The Jetty GzipHandler is a compression handler that you can apply to any dynamic resource (servlet). It fixes many of the bugs in commonly available compression filters: it works with asynchronous servlets; it handles all ways to set content length. It has been tested with Jetty continuations and suspending requests. Some user-agents might be excluded from compression to avoid common browser bugs (yes, this means IE!).

The GzipHandler is added to the entire server by the etc/jetty-gzip.xml file from the gzip.mod module. It may also be added to individual contexts in a context xml file.

Gzip Rules

GzipHandler will gzip or deflate the content of a response if:

  • It is mapped to a matching path
  • The request method is configured to support gzip
  • The request is not from an excluded User-Agent
  • accept-encoding header is set to either gzip, deflate or a combination of those
  • The response status code is >=200 and <300
  • The content length is unknown or more than the minGzipSize initParameter or the minGzipSize is 0(default)
  • The content-type does not match an excluded mime-type
  • No content-encoding is specified by the resource

If both gzip and deflate are specified in the accept-encoding header, then gzip will be used.

Compressing the content can greatly improve the network bandwidth usage, but at the cost of memory and CPU cycles. The DefaultServlet is capable of serving pre-compressed static content, which saves memory and CPU. By default, the GzipHandler will check to see if pre-compressed content exists, and pass the request through to be handled by the DefaultServlet.

Gzip Configuration

Content will only be compressed if content length is either unknown or greater than minGzipSize.
True by default. If set to false, the handler will not check for pre-compressed content.
The compression level used for deflate compression. (0-9).
List of HTTP methods to compress. If not set, only GET requests are compressed.
List of MIME types to compress.
List of MIME types not to compress.
A list of regex patterns for User-Agent names from which requests should not be compressed.
List of paths to exclude from compression. Performs a String.startsWith(String) comparison to check if the path matches. If it does match then there is no compression. To match subpaths use excludePathPatterns instead.
List of paths to consider for compression.
List of paths to definitely consider for compression.

See an error or something missing? Contribute to this documentation at Github!(Generated: 2016-10-14)