mod_lua.xml revision 78f94f1d06c4e6828ce04d618221e0fcecb57849
fb51a6b789d85113d0976148685b0063c294220drbowen<!DOCTYPE modulesynopsis SYSTEM "/style/modulesynopsis.dtd">
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen<?xml-stylesheet type="text/xsl" href="/style/manual.en.xsl"?>
77a0265761f1bec2aaa0b4116c644f8066e349e3rbowen<!-- $LastChangedRevision$ -->
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen Licensed to the Apache Software Foundation (ASF) under one or more
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen contributor license agreements. See the NOTICE file distributed with
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen this work for additional information regarding copyright ownership.
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen The ASF licenses this file to You under the Apache License, Version 2.0
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen (the "License"); you may not use this file except in compliance with
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen the License. You may obtain a copy of the License at
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen Unless required by applicable law or agreed to in writing, software
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen distributed under the License is distributed on an "AS IS" BASIS,
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen See the License for the specific language governing permissions and
b07b82e44c32825d6226ee801d2ed91555e593d1rbowen limitations under the License.
4b2d52ed83bf31730c8b6bbe7c06d806dc3a0c4erbowen<description>Provides Lua hooks into various portions of the httpd
4b2d52ed83bf31730c8b6bbe7c06d806dc3a0c4erbowenrequest processing</description>
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim<p>This module allows the server to be extended with scripts written in the
889dc1728817c1c56d0c8d894c768614e346d86ecovenerLua programming language. The extension points (hooks) available with
889dc1728817c1c56d0c8d894c768614e346d86ecovener<module>mod_lua</module> include many of the hooks available to
889dc1728817c1c56d0c8d894c768614e346d86ecovenernatively compiled Apache HTTP Server modules, such as mapping requests to
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jimfiles, generating dynamic responses, access control, authentication, and
889dc1728817c1c56d0c8d894c768614e346d86ecovenerauthorization</p>
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim<p>More information on the Lua programming language can be found at the
889dc1728817c1c56d0c8d894c768614e346d86ecovener<a href="http://www.lua.org/">the Lua website</a>.</p>
8548ace6aa09b4d3e463254b53865fb38fbbbc78poirier<note><code>mod_lua</code> is still in experimental state.
8548ace6aa09b4d3e463254b53865fb38fbbbc78poirierUntil it is declared stable, usage and behavior may change
8ad875ad9725307fd052e36abc2938f89f56902csfat any time, even between stable releases of the 2.4.x series.
8ad875ad9725307fd052e36abc2938f89f56902csfBe sure to check the CHANGES file before upgrading.</note>
e19685ea3d8a2a0754a532b464a3d194c9f9a429humbedooh<p>This module holds a great deal of power over httpd, which is both a
ededb790277bba8f7ae292b5385aecc7ac433105humbedoohstrength and a potential security risk. It is <strong>not</strong> recommended
09a561bcc5c1159de86edf7e644cc9777636211ahumbedoohthat you use this module on a server that is shared with users you do not
e19685ea3d8a2a0754a532b464a3d194c9f9a429humbedoohtrust, as it can be abused to change the internal workings of httpd.</p>
4b2d52ed83bf31730c8b6bbe7c06d806dc3a0c4erbowen<section id="basicconf"><title>Basic Configuration</title>
4b2d52ed83bf31730c8b6bbe7c06d806dc3a0c4erbowen<code>mod_lua</code> provides a handler named <code>lua-script</code>,
4b2d52ed83bf31730c8b6bbe7c06d806dc3a0c4erbowenwhich can be used with an <code>AddHandler</code> directive:</p>
4b2d52ed83bf31730c8b6bbe7c06d806dc3a0c4erbowenAddHandler lua-script .lua
249cc9b3d83d3c60666269b90ecb9f1390d32165poirierThis will cause <code>mod_lua</code> to handle requests for files
92e5d4326ae44f79da5cb049470daba604506846poirier<p>For more flexibility, see <directive>LuaMapHandler</directive>.
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen<section id="writinghandlers"><title>Writing Handlers</title>
889dc1728817c1c56d0c8d894c768614e346d86ecovener<p> In the Apache HTTP Server API, the handler is a specific kind of hook
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jimresponsible for generating the response. Examples of modules that include a
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jimhandler are <module>mod_proxy</module>, <module>mod_cgi</module>,
889dc1728817c1c56d0c8d894c768614e346d86ecovener<p><code>mod_lua</code> always looks to invoke a Lua function for the handler, rather than
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowenjust evaluating a script body CGI style. A handler function looks
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowensomething like this:</p>
92e5d4326ae44f79da5cb049470daba604506846poirier-- example handler
92e5d4326ae44f79da5cb049470daba604506846poirierrequire "string"
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim This is the default method name for Lua handlers, see the optional
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim function-name in the LuaMapHandler directive to choose a different
cf7d90693f7579700c4f7e663adb83196f903df1covener entry point.
cf7d90693f7579700c4f7e663adb83196f903df1covenerfunction handle(r)
92e5d4326ae44f79da5cb049470daba604506846poirier r:puts("Hello Lua World!\n")
92e5d4326ae44f79da5cb049470daba604506846poirier if r.method == 'GET' then
92e5d4326ae44f79da5cb049470daba604506846poirier for k, v in pairs( r:parseargs() ) do
a51fa5c4960c597687688fd4a87856d5db51435fhumbedooh r:puts( string.format("%s: %s\n", k, v) )
92e5d4326ae44f79da5cb049470daba604506846poirier elseif r.method == 'POST' then
92e5d4326ae44f79da5cb049470daba604506846poirier for k, v in pairs( r:parsebody() ) do
a51fa5c4960c597687688fd4a87856d5db51435fhumbedooh r:puts( string.format("%s: %s\n", k, v) )
e1fcc3befbb69aab09018a6b8fe15d8816a16076humbedooh r:puts("Unsupported HTTP method " .. r.method)
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowenThis handler function just prints out the uri or form encoded
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowenarguments to a plaintext page.
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowenThis means (and in fact encourages) that you can have multiple
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowenhandlers (or hooks, or filters) in the same script.
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<p><module>mod_authz_core</module> provides a high-level interface to
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfauthorization that is much easier to use than using into the relevant
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfhooks directly. The first argument to the
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<directive module="mod_authz_core">Require</directive> directive gives
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfthe name of the responsible authorization provider. For any
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<directive module="mod_authz_core">Require</directive> line,
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<module>mod_authz_core</module> will call the authorization provider
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfof the given name, passing the rest of the line as parameters. The
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfprovider will then check authorization and pass the result as return
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<p>The authz provider is normally called before authentication. If it needs to
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfknow the authenticated user name (or if the user will be authenticated at
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfall), the provider must return <code>apache2.AUTHZ_DENIED_NO_USER</code>.
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfThis will cause authentication to proceed and the authz provider to be
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfcalled a second time.</p>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<p>The following authz provider function takes two arguments, one ip
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfaddress and one user name. It will allow access from the given ip address
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfwithout authentication, or if the authenticated user matches the second
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfargument:</p>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfrequire 'apache2'
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sffunction authz_check_foo(r, ip, user)
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf if r.useragent_ip == ip then
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf elseif r.user == nil then
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf elseif r.user == user then
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf</highlight>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<p>The following configuration registers this function as provider
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<code>foo</code> and configures it for URL <code>/</code>:</p>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfLuaAuthzProvider foo authz_provider.lua authz_check_foo
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<Location />
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf Require foo 10.1.2.3 john_doe
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf</Location>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf</highlight>
92e5d4326ae44f79da5cb049470daba604506846poirier<section id="writinghooks"><title>Writing Hooks</title>
889dc1728817c1c56d0c8d894c768614e346d86ecovener<p>Hook functions are how modules (and Lua scripts) participate in the
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jimprocessing of requests. Each type of hook exposed by the server exists for
3f1007c62ca8de144598b5d8b4fdc9dda36490dahumbedooha specific purpose, such as mapping requests to the filesystem,
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedoohperforming access control, or setting mimetypes:</p>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td><directive module="mod_lua">LuaQuickHandler</directive></td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td>This is the first hook that will be called after a request has
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh been mapped to a host or virtual host</td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td><directive module="mod_lua">LuaHookTranslateName</directive></td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td>This phase translates the requested URI into a filename on the
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh system. Modules such as <module>mod_alias</module> and
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <module>mod_rewrite</module> operate in this phase.</td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td><directive module="mod_lua">LuaHookMapToStorage</directive></td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td>This phase maps files to their physical, cached or external/proxied storage.
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh It can be used by proxy or caching modules</td>
cd9e08003b18a7744c680c07043543b36b941244humbedooh <td><directive module="mod_lua">LuaHookAccessChecker</directive></td>
cd9e08003b18a7744c680c07043543b36b941244humbedooh <td>This phase checks whether a client has access to a resource. This
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh phase is run before the user is authenticated, so beware.
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td><directive module="mod_lua">LuaHookCheckUserID</directive></td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td>This phase it used to check the negotiated user ID</td>
cd9e08003b18a7744c680c07043543b36b941244humbedooh <td><directive module="mod_lua">LuaHookAuthChecker</directive> or
cd9e08003b18a7744c680c07043543b36b941244humbedooh <directive module="mod_lua">LuaAuthzProvider</directive></td>
cd9e08003b18a7744c680c07043543b36b941244humbedooh <td>This phase authorizes a user based on the negotiated credentials, such as
cd9e08003b18a7744c680c07043543b36b941244humbedooh user ID, client certificate etc.
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td><directive module="mod_lua">LuaHookTypeChecker</directive></td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td>This phase checks the requested file and assigns a content type and
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh a handler to it</td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td><directive module="mod_lua">LuaHookFixups</directive></td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td>This is the final "fix anything" phase before the content handlers
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh are run. Any last-minute changes to the request should be made here.</td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td>fx. <code>.lua</code> files or through <directive module="mod_lua">LuaMapHandler</directive></td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td>This is where the content is handled. Files are read, parsed, some are run,
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh and the result is sent to the client</td>
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh <td>Once a request has been handled, it enters several logging phases,
939b5ecdab2e2265a3915b71862c41f527cce73dhumbedooh which logs the request in either the error or access log</td>
3d0a46e44a6b200a4a152775adea19a9d9d65ac4humbedooh<p>Hook functions are passed the request object as their only argument
3d0a46e44a6b200a4a152775adea19a9d9d65ac4humbedooh(except for LuaAuthzProvider, which also gets passed the arguments from
3d0a46e44a6b200a4a152775adea19a9d9d65ac4humbedoohthe Require directive).
92e5d4326ae44f79da5cb049470daba604506846poirierThey can return any value, depending on the hook, but most commonly
92e5d4326ae44f79da5cb049470daba604506846poirierthey'll return OK, DONE, or DECLINED, which you can write in lua as
92e5d4326ae44f79da5cb049470daba604506846poirier<code>apache2.OK</code>, <code>apache2.DONE</code>, or
92e5d4326ae44f79da5cb049470daba604506846poirier<code>apache2.DECLINED</code>, or else an HTTP status code.</p>
bb57315f942d09c744543fe41e453bd0181fd93ecovener-- example hook that rewrites the URI to a filesystem path.
bb57315f942d09c744543fe41e453bd0181fd93ecovenerrequire 'apache2'
bb57315f942d09c744543fe41e453bd0181fd93ecovenerfunction translate_name(r)
bb57315f942d09c744543fe41e453bd0181fd93ecovener if r.uri == "/translate-name" then
bb57315f942d09c744543fe41e453bd0181fd93ecovener -- we don't care about this URL, give another module a chance
bb57315f942d09c744543fe41e453bd0181fd93ecovener--[[ example hook that rewrites one URI to another URI. It returns a
bb57315f942d09c744543fe41e453bd0181fd93ecovener apache2.DECLINED to give other URL mappers a chance to work on the
bb57315f942d09c744543fe41e453bd0181fd93ecovener substitution, including the core translate_name hook which maps based
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim on the DocumentRoot.
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh Note: Use the early/late flags in the directive to make it run before
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh or after mod_alias.
92e5d4326ae44f79da5cb049470daba604506846poirierrequire 'apache2'
92e5d4326ae44f79da5cb049470daba604506846poirierfunction translate_name(r)
92e5d4326ae44f79da5cb049470daba604506846poirier if r.uri == "/translate-name" then
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen<section id="datastructures"><title>Data Structures</title>
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen <p>The request_rec is mapped in as a userdata. It has a metatable
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen which lets you do useful things with it. For the most part it
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh has the same fields as the request_rec struct, many of which are writeable as
92e5d4326ae44f79da5cb049470daba604506846poirier well as readable. (The table fields' content can be changed, but the
92e5d4326ae44f79da5cb049470daba604506846poirier fields themselves cannot be set to different tables.)</p>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>The AllowOverride options applied to the current request.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>If an authentication check was made, this is set to the type
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The query string arguments extracted from the request
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh (f.x. <code>foo=bar&name=johnsmith</code>)</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>Set to true if this is an HTTP/0.9 style request
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh (e.g. <code>GET /foo</code> (with no headers) )</td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>The realm name used for authorization (if applicable).</td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>The server banner, f.x. <code>Apache HTTP Server/2.4.3 openssl/0.9.8c</code></td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>The basic auth password sent with this request, if any</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The content encoding of the current request</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The content type of the current request, as determined in the
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh type_check phase (f.x. <code>image/gif</code> or <code>text/html</code>)</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>MIME header environment for the response, printed even on errors and
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh persist across internal redirects</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The file name that the request maps to, f.x. /www/example.com/foo.txt. This can be
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh changed in the translate-name or map-to-storage phases of a request to allow the
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh default handler (or script handlers) to serve a different file than what was requested.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The name of the <a href="/handler.html">handler</a> that should serve this request, f.x.
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <code>lua-script</code> if it is to be served by mod_lua. This is typically set by the
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <directive module="mod_mime">AddHandler</directive> or <directive module="core">SetHandler</directive>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh directives, but could also be set via mod_lua to allow another handler to serve up a specific request
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh that would otherwise not be served by it.
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>MIME header environment from the request. This contains headers such as <code>Host,
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>MIME header environment for the response.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The host name, as set by the <code>Host:</code> header or by a full URI.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>Whether or not this request is done via HTTPS</td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>Whether this request is the initial request or a sub-request</td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>The size limit of the request body for this request, or 0 if no limit.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The ID to identify request in access and error log.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The request method, f.x. <code>GET</code> or <code>POST</code>.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>A list of notes that can be passed on from one module to another.</td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>The Options directive applied to the current request.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The PATH_INFO extracted from this request.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The protocol used, f.x. <code>HTTP/1.1</code></td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>Denotes whether this is a proxy request or not. This value is generally set in
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh the post_read_request/translate_name phase of a request.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The contents of the <code>Range:</code> header.</td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>The number of bytes remaining to be read from the request body.</td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>The time the server executable was built.</td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>Whether some authorization is/was required for this request.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The environment variables set for this request.</td>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh <td>The time the server was (re)started, in seconds since the epoch (Jan 1st, 1970)</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The (current) HTTP return code for this request, f.x. <code>200</code> or <code>404</code>.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The request string as sent by the client, f.x. <code>GET /foo/bar HTTP/1.1</code>.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The URI after it has been parsed by httpd</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>If an authentication check has been made, this is set to the name of the authenticated user.</td>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh <td>The IP of the user agent making the request</td>
249cc9b3d83d3c60666269b90ecb9f1390d32165poirier <p>The request_rec has (at least) the following methods:</p>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh r:flush() -- flushes the output buffer
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh </highlight>
249cc9b3d83d3c60666269b90ecb9f1390d32165poirier r:addoutputfilter(name|function) -- add an output filter
2537429a9c5d4388773bb77437e04e5f779bb176humbedooh </highlight>
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh r:sendfile(filename) -- sends an entire file to the client, using sendfile if supported by the current platform
10961a2f60207cb873d889bb28b1f0ef707a4311humbedooh </highlight>
65305d236fe992253daa6ee6b3176a8e0e2d87e1humbedooh r:parseargs() -- returns a Lua table containing the request's query string arguments
2537429a9c5d4388773bb77437e04e5f779bb176humbedooh </highlight>
1b9ab80aa85c16a6654e9273ec4aa3bad576840bhumbedoohr:parsebody([sizeLimit]) -- parse the request body as a POST and return a lua table.
1b9ab80aa85c16a6654e9273ec4aa3bad576840bhumbedooh -- An optional number may be passed to specify the maximum number
1b9ab80aa85c16a6654e9273ec4aa3bad576840bhumbedooh -- of bytes to parse. Default is 8192 bytes.
2537429a9c5d4388773bb77437e04e5f779bb176humbedooh </highlight>
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen r:puts("hello", " world", "!") -- print to response body
2537429a9c5d4388773bb77437e04e5f779bb176humbedooh </highlight>
249cc9b3d83d3c60666269b90ecb9f1390d32165poirier r:write("a single string") -- print to response body
2537429a9c5d4388773bb77437e04e5f779bb176humbedooh </highlight>
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh r:escape_html("<html>test</html>") -- Escapes HTML code and returns the escaped result
1abe2f0d024bcb5d099cef68af06781da4e3270bhumbedooh </highlight>
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen<section id="logging"><title>Logging Functions</title>
92e5d4326ae44f79da5cb049470daba604506846poirier -- examples of logging messages<br />
b60ba9fb00026d3dbca744c6c19afe63cba3a3d1covener r:trace1("This is a trace log message") -- trace1 through trace8 can be used <br />
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen r:debug("This is a debug log message")<br />
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen r:info("This is an info log message")<br />
ad14c3be71733d3fc6dfd139ec6e41384109dd0bhumbedooh r:notice("This is a notice log message")<br />
ad14c3be71733d3fc6dfd139ec6e41384109dd0bhumbedooh r:warn("This is a warn log message")<br />
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen r:err("This is an err log message")<br />
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen r:alert("This is an alert log message")<br />
ad14c3be71733d3fc6dfd139ec6e41384109dd0bhumbedooh r:crit("This is a crit log message")<br />
e27eee5caa6c1bf3853c11253ae82303cff0e40brbowen r:emerg("This is an emerg log message")<br />
92e5d4326ae44f79da5cb049470daba604506846poirier<p>A package named <code>apache2</code> is available with (at least) the following contents.</p>
249cc9b3d83d3c60666269b90ecb9f1390d32165poirier <dd>internal constant OK. Handlers should return this if they've
249cc9b3d83d3c60666269b90ecb9f1390d32165poirier handled the request.</dd>
249cc9b3d83d3c60666269b90ecb9f1390d32165poirier <dd>internal constant DECLINED. Handlers should return this if
249cc9b3d83d3c60666269b90ecb9f1390d32165poirier they are not going to handle the request.</dd>
7152f5d04e3782c5e93016ae2ccd960f8538b83bcovener <dt>apache2.PROXYREQ_NONE, apache2.PROXYREQ_PROXY, apache2.PROXYREQ_REVERSE, apache2.PROXYREQ_RESPONSE</dt>
7152f5d04e3782c5e93016ae2ccd960f8538b83bcovener <dd>internal constants used by <module>mod_proxy</module></dd>
bb565c480bd5ba22f4bb1026f06aff3e1880d450humbedooh <dt>apache2.AUTHZ_DENIED, apache2.AUTHZ_GRANTED, apache2.AUTHZ_NEUTRAL, apache2.AUTHZ_GENERAL_ERROR, apache2.AUTHZ_DENIED_NO_USER</dt>
bb565c480bd5ba22f4bb1026f06aff3e1880d450humbedooh <dd>internal constants used by <module>mod_authz_core</module></dd>
92e5d4326ae44f79da5cb049470daba604506846poirier<p>(Other HTTP status codes are not yet implemented.)</p>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Specify the base path for resolving relative paths for mod_lua directives</description>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
fb51a6b789d85113d0976148685b0063c294220drbowen <p>Specify the base path which will be used to evaluate all
2219c51bf0756c2f6f7deb88a13baf30f141c12epoirier relative paths within mod_lua. If not specified they
fb51a6b789d85113d0976148685b0063c294220drbowen will be resolved relative to the current working directory,
fb51a6b789d85113d0976148685b0063c294220drbowen which may not always work well for a server.</p>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
bb565c480bd5ba22f4bb1026f06aff3e1880d450humbedooh<description>One of once, request, conn, thread -- default is once</description>
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh<syntax>LuaScope once|request|conn|thread|server [min] [max]</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
fb51a6b789d85113d0976148685b0063c294220drbowen <p>Specify the lifecycle scope of the Lua interpreter which will
c994f52ac80f9664d2940e5ccd9e77466572013frbowen be used by handlers in this "Directory." The default is "once"</p>
c994f52ac80f9664d2940e5ccd9e77466572013frbowen <dt>once:</dt> <dd>use the interpreter once and throw it away.</dd>
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim <dt>request:</dt> <dd>use the interpreter to handle anything based on
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim the same file within this request, which is also
c994f52ac80f9664d2940e5ccd9e77466572013frbowen request scoped.</dd>
c994f52ac80f9664d2940e5ccd9e77466572013frbowen <dt>conn:</dt> <dd>Same as request but attached to the connection_rec</dd>
4c5d2aefce1b8d2f1a391aa4b36c323b0394257ehumbedooh <dt>thread:</dt> <dd>Use the interpreter for the lifetime of the thread
154995171968d5fbc34d840ffdb303b5b1f26486humbedooh handling the request (only available with threaded MPMs).</dd>
c994f52ac80f9664d2940e5ccd9e77466572013frbowen <dt>server:</dt> <dd>This one is different than others because the
fb51a6b789d85113d0976148685b0063c294220drbowen server scope is quite long lived, and multiple threads
396c4422f2dc5e4d199a4f84d4504afa0c2fad8ahumbedooh will have the same server_rec. To accommodate this,
396c4422f2dc5e4d199a4f84d4504afa0c2fad8ahumbedooh server scoped Lua states are stored in an apr
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh resource list. The <code>min</code> and <code>max</code> arguments
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh specify the minimum and maximum number of Lua states to keep in the
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh Generally speaking, the <code>thread</code> and <code>server</code> scopes
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh execute roughly 2-3 times faster than the rest, because they don't have to
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh spawn new Lua states on every request (especially with the event MPM, as
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh even keepalive requests will use a new thread for each request). If you are
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh satisfied that your scripts will not have problems reusing a state, then
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh the <code>thread</code> or <code>server</code> scopes should be used for
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh maximum performance. While the <code>thread</code> scope will provide the
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh fastest responses, the <code>server</code> scope will use less memory, as
64fdaa4bd37b26a94cf24d544d31e6f39bc6253ehumbedooh states are pooled, allowing f.x. 1000 threads to share only 100 Lua states,
396c4422f2dc5e4d199a4f84d4504afa0c2fad8ahumbedooh thus using only 10% of the memory required by the <code>thread</code> scope.
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Map a path to a lua handler</description>
fb51a6b789d85113d0976148685b0063c294220drbowen<syntax>LuaMapHandler uri-pattern /path/to/lua/script.lua [function-name]</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
fb51a6b789d85113d0976148685b0063c294220drbowen <p>This directive matches a uri pattern to invoke a specific
fb51a6b789d85113d0976148685b0063c294220drbowen handler function in a specific file. It uses PCRE regular
fb51a6b789d85113d0976148685b0063c294220drbowen expressions to match the uri, and supports interpolating
396c4422f2dc5e4d199a4f84d4504afa0c2fad8ahumbedooh match groups into both the file path and the function name.
396c4422f2dc5e4d199a4f84d4504afa0c2fad8ahumbedooh Be careful writing your regular expressions to avoid security
fb51a6b789d85113d0976148685b0063c294220drbowen issues.</p>
fb926c8c319705c9fe42d55a6ad13d9b0972cb72humbedooh LuaMapHandler /(\w+)/(\w+) /scripts/$1.lua handle_$2
6265962c731aed3af3aa7242b35852f3f181d437humbedooh </highlight>
fb51a6b789d85113d0976148685b0063c294220drbowen handler function handle_show on the lua vm after
fb51a6b789d85113d0976148685b0063c294220drbowen loading that file.</p>
fb51a6b789d85113d0976148685b0063c294220drbowen <p>This would invoke the "handle" function, which
fb51a6b789d85113d0976148685b0063c294220drbowen is the default if no specific function name is
fb51a6b789d85113d0976148685b0063c294220drbowen provided.</p>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Add a directory to lua's package.path</description>
fb51a6b789d85113d0976148685b0063c294220drbowen<syntax>LuaPackagePath /path/to/include/?.lua</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
fb51a6b789d85113d0976148685b0063c294220drbowen <usage><p>Add a path to lua's module search path. Follows the same
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim conventions as lua. This just munges the package.path in the
c994f52ac80f9664d2940e5ccd9e77466572013frbowen lua vms.</p>
6265962c731aed3af3aa7242b35852f3f181d437humbedooh </highlight>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Add a directory to lua's package.cpath</description>
fb51a6b789d85113d0976148685b0063c294220drbowen<syntax>LuaPackageCPath /path/to/include/?.soa</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
fb51a6b789d85113d0976148685b0063c294220drbowen <p>Add a path to lua's shared library search path. Follows the same
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim conventions as lua. This just munges the package.cpath in the
c994f52ac80f9664d2940e5ccd9e77466572013frbowen lua vms.</p>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Configure the compiled code cache.</description>
194cfd38d691d74500b4a1751b58ae92d9a31d0bhumbedooh<contextlist>
194cfd38d691d74500b4a1751b58ae92d9a31d0bhumbedooh<context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
fb51a6b789d85113d0976148685b0063c294220drbowen Specify the behavior of the in-memory code cache. The default
fb51a6b789d85113d0976148685b0063c294220drbowen is stat, which stats the top level script (not any included
fb51a6b789d85113d0976148685b0063c294220drbowen ones) each time that file is needed, and reloads it if the
fb51a6b789d85113d0976148685b0063c294220drbowen modified time indicates it is newer than the one it has
fb51a6b789d85113d0976148685b0063c294220drbowen already loaded. The other values cause it to keep the file
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim cached forever (don't stat and replace) or to never cache the
92e5d4326ae44f79da5cb049470daba604506846poirier <p>In general stat or forever is good for production, and stat or never
3a602d0ba8536a79a780655bb92133b571e38378poirier for development.</p>
6265962c731aed3af3aa7242b35852f3f181d437humbedoohLuaCodeCache stat
6265962c731aed3af3aa7242b35852f3f181d437humbedoohLuaCodeCache forever
6265962c731aed3af3aa7242b35852f3f181d437humbedoohLuaCodeCache never
6265962c731aed3af3aa7242b35852f3f181d437humbedooh </highlight>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Provide a hook for the translate name phase of request processing</description>
457256c49209d6e56bfe63b411688ad9cb2a8429covener<syntax>LuaHookTranslateName /path/to/lua/script.lua hook_function_name [early|late]</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
247c1db2eb82d5c836df7bafc7380887890e11a2rjung<compatibility>The optional third argument is supported in 2.3.15 and later</compatibility>
fb51a6b789d85113d0976148685b0063c294220drbowen Add a hook (at APR_HOOK_MIDDLE) to the translate name phase of
fb51a6b789d85113d0976148685b0063c294220drbowen request processing. The hook function receives a single
860b4efe27e7c1c9a2bf5c872b29c90f76849b51jim argument, the request_rec, and should return a status code,
fb51a6b789d85113d0976148685b0063c294220drbowen which is either an HTTP error code, or the constants defined
fb51a6b789d85113d0976148685b0063c294220drbowen in the apache2 module: apache2.OK, apache2.DECLINED, or
fb51a6b789d85113d0976148685b0063c294220drbowen <p>For those new to hooks, basically each hook will be invoked
fb51a6b789d85113d0976148685b0063c294220drbowen until one of them returns apache2.OK. If your hook doesn't
fb51a6b789d85113d0976148685b0063c294220drbowen want to do the translation it should just return
fb51a6b789d85113d0976148685b0063c294220drbowen apache2.DECLINED. If the request should stop processing, then
92e5d4326ae44f79da5cb049470daba604506846poirierLuaHookTranslateName /scripts/conf/hooks.lua silly_mapper
92e5d4326ae44f79da5cb049470daba604506846poirierrequire "apache2"
92e5d4326ae44f79da5cb049470daba604506846poirierfunction silly_mapper(r)
92e5d4326ae44f79da5cb049470daba604506846poirier if r.uri == "/" then
457256c49209d6e56bfe63b411688ad9cb2a8429covener <note><title>Context</title><p>This directive is not valid in <directive
457256c49209d6e56bfe63b411688ad9cb2a8429covener type="section" module="core">Directory</directive>, <directive
457256c49209d6e56bfe63b411688ad9cb2a8429covener type="section" module="core">Files</directive>, or htaccess
457256c49209d6e56bfe63b411688ad9cb2a8429covener <note><title>Ordering</title><p>The optional arguments "early" or "late"
457256c49209d6e56bfe63b411688ad9cb2a8429covener control when this script runs relative to other modules.</p></note>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh<description>Provide a hook for the fixups phase of a request
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowenprocessing</description>
fb51a6b789d85113d0976148685b0063c294220drbowen<syntax>LuaHookFixups /path/to/lua/script.lua hook_function_name</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
fb51a6b789d85113d0976148685b0063c294220drbowen Just like LuaHookTranslateName, but executed at the fixups phase
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Provide a hook for the map_to_storage phase of request processing</description>
fb51a6b789d85113d0976148685b0063c294220drbowen<syntax>LuaHookMapToStorage /path/to/lua/script.lua hook_function_name</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh <p>Like <directive>LuaHookTranslateName</directive> but executed at the
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh map-to-storage phase of a request. Modules like mod_cache run at this phase,
194cfd38d691d74500b4a1751b58ae92d9a31d0bhumbedooh which makes for an interesting example on what to do here:</p>
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh LuaHookMapToStorage /path/to/lua/script.lua check_cache
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh </highlight>
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedoohrequire"apache2"
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedoohcached_files = {}
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedoohfunction read_file(filename)
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh local input = io.open(filename, "r")
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh if input then
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh local data = input:read("*a")
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh cached_files[filename] = data
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh file = cached_files[filename]
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh input:close()
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh return cached_files[filename]
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedoohfunction check_cache(r)
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh if r.filename:match("%.png$") then -- Only match PNG files
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh local file = cached_files[r.filename] -- Check cache entries
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh if not file then
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh file = read_file(r.filename) -- Read file into cache
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh if file then -- If file exists, write it out
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh r:write(file)
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh r:info(("Sent %s to client from cache"):format(r.filename))
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh return apache2.DONE -- skip default handler for PNG files
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh return apache2.DECLINED -- If we had nothing to do, let others serve this.
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh </highlight>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Provide a hook for the check_user_id phase of request processing</description>
457256c49209d6e56bfe63b411688ad9cb2a8429covener<syntax>LuaHookCheckUserID /path/to/lua/script.lua hook_function_name [early|late]</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
247c1db2eb82d5c836df7bafc7380887890e11a2rjung<compatibility>The optional third argument is supported in 2.3.15 and later</compatibility>
457256c49209d6e56bfe63b411688ad9cb2a8429covener <note><title>Ordering</title><p>The optional arguments "early" or "late"
457256c49209d6e56bfe63b411688ad9cb2a8429covener control when this script runs relative to other modules.</p></note>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Provide a hook for the type_checker phase of request processing</description>
fb51a6b789d85113d0976148685b0063c294220drbowen<syntax>LuaHookTypeChecker /path/to/lua/script.lua hook_function_name</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh This directive provides a hook for the type_checker phase of the request processing.
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh This phase is where requests are assigned a content type and a handler, and thus can
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh be used to modify the type and handler based on input:
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh LuaHookTypeChecker /path/to/lua/script.lua type_checker
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh </highlight>
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh function type_checker(r)
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh if r.uri:match("%.to_gif$") then -- match foo.png.to_gif
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh r.content_type = "image/gif" -- assign it the image/gif type
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh r.handler = "gifWizard" -- tell the gifWizard module to handle this
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh r.filename = r.uri:gsub("%.to_gif$", "") -- fix the filename requested
2d4c56d61d0746f3d3bd08f61936631037a8c23chumbedooh </highlight>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
9cd56c73a0fd508522ba2f6bc6c9839c478c61c3rbowen<description>Provide a hook for the auth_checker phase of request processing</description>
457256c49209d6e56bfe63b411688ad9cb2a8429covener<syntax>LuaHookAuthChecker /path/to/lua/script.lua hook_function_name [early|late]</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
247c1db2eb82d5c836df7bafc7380887890e11a2rjung<compatibility>The optional third argument is supported in 2.3.15 and later</compatibility>
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier<p>Invoke a lua function in the auth_checker phase of processing
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poiriera request. This can be used to implement arbitrary authentication
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirierand authorization checking. A very simple example:
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirierrequire 'apache2'
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier-- fake authcheck hook
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier-- If request has no auth info, set the response header and
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier-- return a 401 to ask the browser for basic auth info.
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier-- If request has auth info, don't actually look at it, just
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier-- pretend we got userid 'foo' and validated it.
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier-- Then check if the userid is 'foo' and accept the request.
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirierfunction authcheck_hook(r)
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier -- look for auth info
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier auth = r.headers_in['Authorization']
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier if auth ~= nil then
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier -- fake the user
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier if r.user == nil then
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier r:debug("authcheck: user is nil, returning 401")
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier r.err_headers_out['WWW-Authenticate'] = 'Basic realm="WallyWorld"'
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier elseif r.user == "foo" then
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier r:debug('user foo: OK')
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier r:debug("authcheck: user='" .. r.user .. "'")
768c8bcc0d91d1c3c04b0f80c309d31c6182fbf8poirier r.err_headers_out['WWW-Authenticate'] = 'Basic realm="WallyWorld"'
457256c49209d6e56bfe63b411688ad9cb2a8429covener <note><title>Ordering</title><p>The optional arguments "early" or "late"
457256c49209d6e56bfe63b411688ad9cb2a8429covener control when this script runs relative to other modules.</p></note>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
9cd56c73a0fd508522ba2f6bc6c9839c478c61c3rbowen<description>Provide a hook for the access_checker phase of request processing</description>
457256c49209d6e56bfe63b411688ad9cb2a8429covener<syntax>LuaHookAccessChecker /path/to/lua/script.lua hook_function_name [early|late]</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
247c1db2eb82d5c836df7bafc7380887890e11a2rjung<compatibility>The optional third argument is supported in 2.3.15 and later</compatibility>
92e5d4326ae44f79da5cb049470daba604506846poirier<p>Add your hook to the access_checker phase. An access checker
92e5d4326ae44f79da5cb049470daba604506846poirierhook function usually returns OK, DECLINED, or HTTP_FORBIDDEN.</p>
457256c49209d6e56bfe63b411688ad9cb2a8429covener <note><title>Ordering</title><p>The optional arguments "early" or "late"
457256c49209d6e56bfe63b411688ad9cb2a8429covener control when this script runs relative to other modules.</p></note>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
fb51a6b789d85113d0976148685b0063c294220drbowen<directivesynopsis>
9cd56c73a0fd508522ba2f6bc6c9839c478c61c3rbowen<description>Provide a hook for the insert_filter phase of request processing</description>
fb51a6b789d85113d0976148685b0063c294220drbowen<syntax>LuaHookInsertFilter /path/to/lua/script.lua hook_function_name</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<context>directory</context><context>.htaccess</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
fb51a6b789d85113d0976148685b0063c294220drbowen</directivesynopsis>
ae600ca541efc686b34f8b1f21bd3d0741d37674covener<directivesynopsis>
ae600ca541efc686b34f8b1f21bd3d0741d37674covener<description>Controls how parent configuration sections are merged into children</description>
ae600ca541efc686b34f8b1f21bd3d0741d37674covener<syntax>LuaInherit none|parent-first|parent-last</syntax>
ae600ca541efc686b34f8b1f21bd3d0741d37674covener<contextlist><context>server config</context><context>virtual host</context>
ae600ca541efc686b34f8b1f21bd3d0741d37674covener<context>directory</context><context>.htaccess</context>
ae600ca541efc686b34f8b1f21bd3d0741d37674covener</contextlist>
ae600ca541efc686b34f8b1f21bd3d0741d37674covener <usage><p>By default, if LuaHook* directives are used in overlapping
ae600ca541efc686b34f8b1f21bd3d0741d37674covener Directory or Location configuration sections, the scripts defined in the
ae600ca541efc686b34f8b1f21bd3d0741d37674covener more specific section are run <em>after</em> those defined in the more
ae600ca541efc686b34f8b1f21bd3d0741d37674covener generic section (LuaInherit parent-first). You can reverse this order, or
ae600ca541efc686b34f8b1f21bd3d0741d37674covener make the parent context not apply at all.</p>
ae600ca541efc686b34f8b1f21bd3d0741d37674covener <p> In previous 2.3.x releases, the default was effectively to ignore LuaHook*
ae600ca541efc686b34f8b1f21bd3d0741d37674covener directives from parent configuration sections.</p></usage>
ae600ca541efc686b34f8b1f21bd3d0741d37674covener</directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<directivesynopsis>
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen<description>Provide a hook for the quick handler of request processing</description>
35b6187510aac978a1e2a242560ef5fff9f09e8ehumbedooh<syntax>LuaQuickHandler /path/to/script.lua hook_function_name</syntax>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic<contextlist><context>server config</context><context>virtual host</context>
99e316bc4b9b2b5754165939ac14b6d16132cce1igalic</contextlist>
72b1f0c347c49fa217617de9864e4f30cfa0cbd4humbedooh This phase is run immediately after the request has been mapped to a virtal host,
72b1f0c347c49fa217617de9864e4f30cfa0cbd4humbedooh and can be used to either do some request processing before the other phases kick
72b1f0c347c49fa217617de9864e4f30cfa0cbd4humbedooh in, or to serve a request without the need to translate, map to storage et cetera.
72b1f0c347c49fa217617de9864e4f30cfa0cbd4humbedooh As this phase is run before anything else, directives such as <directive
72b1f0c347c49fa217617de9864e4f30cfa0cbd4humbedooh type="section" module="core">Location</directive> or <directive
72b1f0c347c49fa217617de9864e4f30cfa0cbd4humbedooh type="section" module="core">Directory</directive> are void in this phase, just as
72b1f0c347c49fa217617de9864e4f30cfa0cbd4humbedooh URIs have not been properly parsed yet.
457256c49209d6e56bfe63b411688ad9cb2a8429covener <note><title>Context</title><p>This directive is not valid in <directive
457256c49209d6e56bfe63b411688ad9cb2a8429covener type="section" module="core">Directory</directive>, <directive
457256c49209d6e56bfe63b411688ad9cb2a8429covener type="section" module="core">Files</directive>, or htaccess
6b4cd1f143d5d7244d2476d1e28456212faddb72rbowen</directivesynopsis>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<directivesynopsis>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<description>Plug an authorization provider function into <module>mod_authz_core</module>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf</description>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<syntax>LuaAuthzProvider provider_name /path/to/lua/script.lua function_name</syntax>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<contextlist><context>server config</context> </contextlist>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<p>After a lua function has been registered as authorization provider, it can be used
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfwith the <directive module="mod_authz_core">Require</directive> directive:</p>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sfLuaAuthzProvider foo authz.lua authz_check_foo
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf<Location />
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedooh Require foo johndoe
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf</Location>
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf</highlight>
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedoohrequire "apache2"
890b9ed4c432913c66d39ef44823c2ec5f63fbe8humbedoohfunction authz_check_foo(r, who)
e20c6ecbd465cd7dabb44acea6afafc7925f3a03sf</directivesynopsis>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<directivesynopsis>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<description>Provide a Lua function for content input filtering</description>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<syntax>LuaInputFilter filter_name /path/to/lua/script.lua function_name</syntax>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<contextlist><context>server config</context> </contextlist>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<p>Provides a means of adding a Lua function as an input filter.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohAs with output filters, input filters work as coroutines,
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohfirst yielding before buffers are sent, then yielding whenever
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooha bucket needs to be passed down the chain, and finally (optionally)
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohyielding anything that needs to be appended to the input data. The
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohglobal variable <code>bucket</code> holds the buckets as they are passed
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohonto the Lua script:
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohLuaInputFilter myInputFilter /www/filter.lua input_filter
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<FilesMatch "\.lua>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh SetInputFilter myInputFilter
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh</FilesMatch>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh Example input filter that converts all POST data to uppercase.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohfunction input_filter(r)
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh print("luaInputFilter called") -- debug print
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield() -- Yield and wait for buckets
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh while bucket do -- For each bucket, do...
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh local output = string.upper(bucket) -- Convert all POST data to uppercase
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield(output) -- Send converted data down the chain
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- No more buckets available.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield("&filterSignature=1234") -- Append signature at the end
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohThe input filter supports denying/skipping a filter if it is deemed unwanted:
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohfunction input_filter(r)
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh if not good then
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh return -- Simply deny filtering, passing on the original content instead
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield() -- wait for buckets
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh ... -- insert filter stuff here
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohSee "<a href="#modifying_buckets">Modifying contents with Lua
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohfilters</a>" for more information.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh</directivesynopsis>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<directivesynopsis>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<description>Provide a Lua function for content output filtering</description>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<syntax>LuaOutputFilter filter_name /path/to/lua/script.lua function_name</syntax>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<contextlist><context>server config</context> </contextlist>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<p>Provides a means of adding a Lua function as an output filter.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohAs with input filters, output filters work as coroutines,
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohfirst yielding before buffers are sent, then yielding whenever
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooha bucket needs to be passed down the chain, and finally (optionally)
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohyielding anything that needs to be appended to the input data. The
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohglobal variable <code>bucket</code> holds the buckets as they are passed
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohonto the Lua script:
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohLuaOutputFilter myOutputFilter /www/filter.lua output_filter
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh<FilesMatch "\.lua>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh SetOutputFilter myOutputFilter
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh</FilesMatch>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh Example output filter that escapes all HTML entities in the output
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohfunction output_filter(r)
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield("(Handled by myOutputFilter)<br/>\n") -- Prepend some data to the output,
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- yield and wait for buckets.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh while bucket do -- For each bucket, do...
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh local output = r:escape_html(bucket) -- Escape all output
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield(output) -- Send converted data down the chain
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- No more buckets available.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohAs with the input filter, the output filter supports denying/skipping a filter
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohif it is deemed unwanted:
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohfunction output_filter(r)
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh return -- Simply deny filtering, passing on the original content instead
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield() -- wait for buckets
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh ... -- insert filter stuff here
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohSee "<a href="#modifying_buckets">Modifying contents with Lua filters</a>" for more
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh</directivesynopsis>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh <title>Modifying contents with Lua filters</title>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh Filter functions implemented via <directive module="mod_lua">LuaInputFilter</directive>
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh or <directive module="mod_lua">LuaOutputFilter</directive> are designed as
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh three-stage non-blocking functions using coroutines to suspend and resume a
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh function as buckets are sent down the filter chain. The core structure of
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh such a function is:
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedoohfunction filter(r)
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- Our first yield is to signal that we are ready to receive buckets.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- Before this yield, we can set up our environment, check for conditions,
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- and, if we deem it necessary, decline filtering a request alltogether:
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh if something_bad then
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh return -- This would skip this filter.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- Regardless of whether we have data to prepend, a yield MUST be called here.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- Note that only output filters can prepend data. Input filters must use the
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- final stage to append data to the content.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield([optional header to be prepended to the content])
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- After we have yielded, buckets will be sent to us, one by one, and we can
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- do whatever we want with them and then pass on the result.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- Buckets are stored in the global variable 'bucket', so we create a loop
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- that checks if 'bucket' is not nil:
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh while bucket ~= nil do
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh local output = mangle(bucket) -- Do some stuff to the content
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield(output) -- Return our new content to the filter chain
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- Once the buckets are gone, 'bucket' is set to nil, which will exit the
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- loop and land us here. Anything extra we want to append to the content
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- can be done by doing a final yield here. Both input and output filters
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh -- can append data to the content in this phase.
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh coroutine.yield([optional footer to be appended to the content])
78f94f1d06c4e6828ce04d618221e0fcecb57849humbedooh </highlight>
fb51a6b789d85113d0976148685b0063c294220drbowen</modulesynopsis>