Plugin Reference
****************

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Overview
========

One of the key features of Apache Traffic Server is modularity.
Features that aren't needed in the core simply aren't there. This
is a good thing, because it guarantees that our core can remain
fast by concentrating on the things that we always provide: Caching
and proxying.

All other things can be moved into plugins, by opening up a consistent
C API, everyone can implement their own functionality, without
having to touch the core.

Stable plugins
==============

Plugins that are considered stable are installed by default in
Apache Traffic Server releases.

.. toctree::
  :maxdepth: 1

  CacheURL Plugin: allows you to change the key that is used for caching a request by using any portion of the url via regex <cacheurl.en>
  conf_remap Plugin: allows you to override configuration directives dependent on actual remapping rules <conf_remap.en>
  gzip / deflate Plugin: gzips or deflates responses <gzip.en>
  Header Rewrite Plugin: allows you to modify various headers based on defined rules (operations) on a request or response <header_rewrite.en>
  Regex Remap Plugin: allows you to configure mapping rules based on regular expressions <regex_remap.en>
  Stats over HTTP Plugin: implements an HTTP interface to all Traffic Server statistics <stats_over_http.en>
  TCPInfo Plugin: logs TCP metrics at various points in the HTTP processing pipeline <tcpinfo.en>

Experimental plugins
====================

Plugins that are considered experimental are located in the
`plugins/experimental <https://git-wip-us.apache.org/repos/asf?p=trafficserver.git;a=tree;f=plugins/experimental;hb=HEAD>`_
directory of the Apache Traffic Server source tree. Exmperimental plugins can be compiled by passing the
`--enable-experimental-plugins` option to `configure`::

    $ autoconf -i
    $ ./configure --enable-experimental-plugins
    $ make

.. toctree::
  :maxdepth: 1

  AuthProxy Plugin: delegates the authorization decision of a request to an external HTTP service <authproxy.en>
  Background Fetch Plugin: allows you to proactively fetch content from Origin in a way that it will fill the object into cache <background_fetch.en>
  Balancer Plugin: balances requests across multiple origin servers <balancer.en>
  Buffer Upload Plugin: buffers POST data before connecting to the Origin server <buffer_upload.en>
  Combohandler Plugin: provides an intelligent way to combine multiple URLs into a single URL, and have Apache Traffic Server combine the components into one response <combo_handler.en>
  Epic Plugin: emits Traffic Server metrics in a format that is consumed tby the Epic Network Monitoring System <epic.en>
  ESI Plugin: implements the ESI specification <esi.en>
  GeoIP ACLs Plugin: denying (or allowing) requests based on the source IP geo-location <geoip_acl.en>
  hipes.en 
  Metalink Plugin: implements the Metalink download description format in order to try not to download the same file twice. <metalink.en>
  MySQL Remap Plugin: allows dynamic “remaps” from a database <mysql_remap.en>
  AWS S3 Authentication plugin: provides support for the Amazon S3 authentication features <s3_auth.en>
  stale_while_revalidate.en 
  ts-lua Plugin: allows plugins to be written in Lua instead of C code <ts_lua.en>
  XDebug Plugin: allows HTTP clients to debug the operation of the Traffic Server cache using the X-Debug header <xdebug.en>