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<p class="menu"><a href="/mod/">Modules</a> | <a href="/mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="/glossary.html">Glossary</a> | <a href="/sitemap.html">Sitemap</a></p>
<p class="apache">Apache HTTP Server Version 2.5</p>
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<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.5</a> > <a href="./">Modules</a></div>
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<div id="preamble"><h1>Apache Module mod_lua</h1>
<div class="toplang">
<p><span>Available Languages: </span><a href="/en/mod/mod_lua.html" title="English"> en </a> |
<a href="/fr/mod/mod_lua.html" hreflang="fr" rel="alternate" title="Fran�ais"> fr </a></p>
</div>
<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Provides Lua hooks into various portions of the httpd
request processing</td></tr>
<tr><th><a href="module-dict.html#ModuleIdentifier">Module�Identifier:</a></th><td>lua_module</td></tr>
<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>2.3 and later</td></tr></table>
<h3>Summary</h3>
<p>This module allows the server to be extended with scripts written in the
Lua programming language. The extension points (hooks) available with
<code class="module"><a href="/mod/mod_lua.html">mod_lua</a></code> include many of the hooks available to
natively compiled Apache HTTP Server modules, such as mapping requests to
files, generating dynamic responses, access control, authentication, and
authorization</p>
<p>More information on the Lua programming language can be found at the
<div class="note"><code>mod_lua</code> is still in experimental state.
Until it is declared stable, usage and behavior may change
at any time, even between stable releases of the 2.4.x series.
Be sure to check the CHANGES file before upgrading.</div>
<div class="warning"><h3>Warning</h3>
<p>This module holds a great deal of power over httpd, which is both a
strength and a potential security risk. It is <strong>not</strong> recommended
that you use this module on a server that is shared with users you do not
trust, as it can be abused to change the internal workings of httpd.</p>
</div>
</div>
<div id="quickview"><h3 class="directives">Directives</h3>
<ul id="toc">
<li><img alt="" src="/images/down.gif" /> <a href="#luahookaccesschecker">LuaHookAccessChecker</a></li>
<li><img alt="" src="/images/down.gif" /> <a href="#luahookinsertfilter">LuaHookInsertFilter</a></li>
<li><img alt="" src="/images/down.gif" /> <a href="#luahookmaptostorage">LuaHookMapToStorage</a></li>
<li><img alt="" src="/images/down.gif" /> <a href="#luahooktranslatename">LuaHookTranslateName</a></li>
</ul>
<h3>Topics</h3>
<ul id="topics">
<li><img alt="" src="/images/down.gif" /> <a href="#writingauthzproviders">Writing Authorization Providers</a></li>
</ul><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div>
<div class="section">
<h2><a name="basicconf" id="basicconf">Basic Configuration</a></h2>
<p>The basic module loading directive is</p>
<pre class="prettyprint lang-config">
LoadModule lua_module modules/mod_lua.so
</pre>
<p>
<code>mod_lua</code> provides a handler named <code>lua-script</code>,
which can be used with an <code>AddHandler</code> directive:</p>
<pre class="prettyprint lang-config">
AddHandler lua-script .lua
</pre>
<p>
This will cause <code>mod_lua</code> to handle requests for files
ending in <code>.lua</code> by invoking that file's
<code>handle</code> function.
</p>
<p>For more flexibility, see <code class="directive">LuaMapHandler</code>.
</p>
<div class="section">
<h2><a name="writinghandlers" id="writinghandlers">Writing Handlers</a></h2>
<p> In the Apache HTTP Server API, the handler is a specific kind of hook
responsible for generating the response. Examples of modules that include a
handler are <code class="module"><a href="/mod/mod_proxy.html">mod_proxy</a></code>, <code class="module"><a href="/mod/mod_cgi.html">mod_cgi</a></code>,
<p><code>mod_lua</code> always looks to invoke a Lua function for the handler, rather than
just evaluating a script body CGI style. A handler function looks
something like this:</p>
<pre class="prettyprint lang-lua">
-- example handler
require "string"
--[[
This is the default method name for Lua handlers, see the optional
function-name in the LuaMapHandler directive to choose a different
entry point.
--]]
function handle(r)
r:puts("Hello Lua World!\n")
if r.method == 'GET' then
for k, v in pairs( r:parseargs() ) do
r:puts( string.format("%s: %s\n", k, v) )
end
elseif r.method == 'POST' then
for k, v in pairs( r:parsebody() ) do
r:puts( string.format("%s: %s\n", k, v) )
end
else
r:puts("Unsupported HTTP method " .. r.method)
end
end
</pre>
<p>
This handler function just prints out the uri or form encoded
arguments to a plaintext page.
</p>
<p>
This means (and in fact encourages) that you can have multiple
handlers (or hooks, or filters) in the same script.
</p>
<div class="section">
<h2><a name="writingauthzproviders" id="writingauthzproviders">Writing Authorization Providers</a></h2>
<p><code class="module"><a href="/mod/mod_authz_core.html">mod_authz_core</a></code> provides a high-level interface to
authorization that is much easier to use than using into the relevant
hooks directly. The first argument to the
<code class="directive"><a href="/mod/mod_authz_core.html#require">Require</a></code> directive gives
the name of the responsible authorization provider. For any
<code class="module"><a href="/mod/mod_authz_core.html">mod_authz_core</a></code> will call the authorization provider
of the given name, passing the rest of the line as parameters. The
provider will then check authorization and pass the result as return
value.</p>
<p>The authz provider is normally called before authentication. If it needs to
know the authenticated user name (or if the user will be authenticated at
This will cause authentication to proceed and the authz provider to be
called a second time.</p>
<p>The following authz provider function takes two arguments, one ip
address and one user name. It will allow access from the given ip address
without authentication, or if the authenticated user matches the second
argument:</p>
<pre class="prettyprint lang-lua">
require 'apache2'
function authz_check_foo(r, ip, user)
if r.useragent_ip == ip then
return apache2.AUTHZ_GRANTED
elseif r.user == nil then
return apache2.AUTHZ_DENIED_NO_USER
elseif r.user == user then
return apache2.AUTHZ_GRANTED
else
return apache2.AUTHZ_DENIED
end
end
</pre>
<p>The following configuration registers this function as provider
<code>foo</code> and configures it for URL <code>/</code>:</p>
<pre class="prettyprint lang-config">
LuaAuthzProvider foo authz_provider.lua authz_check_foo
<Location />
Require foo 10.1.2.3 john_doe
</Location>
</pre>
<div class="section">
<h2><a name="writinghooks" id="writinghooks">Writing Hooks</a></h2>
<p>Hook functions are how modules (and Lua scripts) participate in the
processing of requests. Each type of hook exposed by the server exists for
a specific purposes such as mapping requests to the filesystem,
performing access control, or setting mimetypes:</p>
<table class="bordered"><tr class="header">
<th>Hook phase</th>
<th>mod_lua directive</th>
<th>Description</th>
</tr>
<tr>
<td>Quick handler</td>
<td><code class="directive"><a href="#luaquickhandler">LuaQuickHandler</a></code></td>
<td>This is the first hook that will be called after a request has
been mapped to a host or virtual host</td>
</tr>
<tr class="odd">
<td>Translate name</td>
<td><code class="directive"><a href="#luahooktranslatename">LuaHookTranslateName</a></code></td>
<td>This phase translates the requested URI into a filename on the
<code class="module"><a href="/mod/mod_rewrite.html">mod_rewrite</a></code> operate in this phase.</td>
</tr>
<tr>
<td>Map to storage</td>
<td><code class="directive"><a href="#luahookmaptostorage">LuaHookMapToStorage</a></code></td>
It can be used by proxy or caching modules</td>
</tr>
<tr class="odd">
<td>Check Access</td>
<td><code class="directive"><a href="#luahookaccesschecker">LuaHookAccessChecker</a></code></td>
<td>This phase checks whether a client has access to a resource. This
phase is run before the user is authenticated, so beware.
</td>
</tr>
<tr>
<td>Check User ID</td>
<td><code class="directive"><a href="#luahookcheckuserid">LuaHookCheckUserID</a></code></td>
<td>This phase it used to check the negotiated user ID</td>
</tr>
<tr class="odd">
<td>Check Authorization</td>
<td><code class="directive"><a href="#luahookauthchecker">LuaHookAuthChecker</a></code> or
<code class="directive"><a href="#luaauthzprovider">LuaAuthzProvider</a></code></td>
<td>This phase authorizes a user based on the negotiated credentials, such as
user ID, client certificate etc.
</td>
</tr>
<tr>
<td>Check Type</td>
<td><code class="directive"><a href="#luahooktypechecker">LuaHookTypeChecker</a></code></td>
<td>This phase checks the requested file and assigns a content type and
a handler to it</td>
</tr>
<tr class="odd">
<td>Fixups</td>
<td><code class="directive"><a href="#luahookfixups">LuaHookFixups</a></code></td>
<td>This is the final "fix anything" phase before the content handlers
are run. Any last-minute changes to the request should be made here.</td>
</tr>
<tr>
<td>Content handler</td>
<td>fx. <code>.lua</code> files or through <code class="directive"><a href="#luamaphandler">LuaMapHandler</a></code></td>
<td>This is where the content is handled. Files are read, parsed, some are run,
and the result is sent to the client</td>
</tr>
<tr class="odd">
<td>Logging</td>
<td>(none)</td>
<td>Once a request has been handled, it enters several logging phases,
which logs the request in either the error or access log</td>
</tr>
</table>
<p>Hook functions are passed the request object as their only argument.
They can return any value, depending on the hook, but most commonly
they'll return OK, DONE, or DECLINED, which you can write in lua as
<pre class="prettyprint lang-lua">
-- example hook that rewrites the URI to a filesystem path.
require 'apache2'
function translate_name(r)
if r.uri == "/translate-name" then
return apache2.OK
end
-- we don't care about this URL, give another module a chance
return apache2.DECLINED
end
</pre>
<pre class="prettyprint lang-lua">
--[[ example hook that rewrites one URI to another URI. It returns a
apache2.DECLINED to give other URL mappers a chance to work on the
substitution, including the core translate_name hook which maps based
on the DocumentRoot.
or after mod_alias.
--]]
require 'apache2'
function translate_name(r)
if r.uri == "/translate-name" then
r.uri = "/find_me.txt"
return apache2.DECLINED
end
return apache2.DECLINED
end
</pre>
<div class="section">
<h2><a name="datastructures" id="datastructures">Data Structures</a></h2>
<dl>
<dt>request_rec</dt>
<dd>
<p>The request_rec is mapped in as a userdata. It has a metatable
which lets you do useful things with it. For the most part it
has the same fields as the request_rec struct, many of which are writeable as
well as readable. (The table fields' content can be changed, but the
fields themselves cannot be set to different tables.)</p>
<table class="bordered"><tr class="header">
<th><strong>Name</strong></th>
<th><strong>Lua type</strong></th>
<th><strong>Writable</strong></th>
<th><strong>Description</strong></th>
</tr>
<tr>
<td><code>ap_auth_type</code></td>
<td>string</td>
<td>no</td>
<td>If an authentication check was made, this is set to the type
</tr>
<tr class="odd">
<td><code>args</code></td>
<td>string</td>
<td>yes</td>
<td>The query string arguments extracted from the request
</tr>
<tr>
<td><code>assbackwards</code></td>
<td>boolean</td>
<td>no</td>
</tr>
<tr class="odd">
<td><code>canonical_filename</code></td>
<td>string</td>
<td>no</td>
<td>The canonical filename of the request</td>
</tr>
<tr>
<td><code>content_encoding</code></td>
<td>string</td>
<td>no</td>
<td>The content encoding of the current request</td>
</tr>
<tr class="odd">
<td><code>content_type</code></td>
<td>string</td>
<td>yes</td>
<td>The content type of the current request, as determined in the
</tr>
<tr>
<td><code>context_prefix</code></td>
<td>string</td>
<td>no</td>
<td />
</tr>
<tr class="odd">
<td><code>context_document_root</code></td>
<td>string</td>
<td>no</td>
<td />
</tr>
<tr>
<td><code>document_root</code></td>
<td>string</td>
<td>no</td>
<td>The document root of the host</td>
</tr>
<tr class="odd">
<td><code>err_headers_out</code></td>
<td>table</td>
<td>no</td>
<td>MIME header environment for the response, printed even on errors and
persist across internal redirects</td>
</tr>
<tr>
<td><code>filename</code></td>
<td>string</td>
<td>yes</td>
changed in the translate-name or map-to-storage phases of a request to allow the
default handler (or script handlers) to serve a different file than what was requested.</td>
</tr>
<tr class="odd">
<td><code>handler</code></td>
<td>string</td>
<td>yes</td>
<code>lua-script</code> if it is to be served by mod_lua. This is typically set by the
<code class="directive"><a href="/mod/mod_mime.html#addhandler">AddHandler</a></code> or <code class="directive"><a href="/mod/core.html#sethandler">SetHandler</a></code>
directives, but could also be set via mod_lua to allow another handler to serve up a specific request
that would otherwise not be served by it.
</td>
</tr>
<tr>
<td><code>headers_in</code></td>
<td>table</td>
<td>yes</td>
<td>MIME header environment from the request. This contains headers such as <code>Host,
User-Agent, Referer</code> and so on.</td>
</tr>
<tr class="odd">
<td><code>headers_out</code></td>
<td>table</td>
<td>yes</td>
<td>MIME header environment for the response.</td>
</tr>
<tr>
<td><code>hostname</code></td>
<td>string</td>
<td>no</td>
<td>The host name, as set by the <code>Host:</code> header or by a full URI.</td>
</tr>
<tr class="odd">
<td><code>is_https</code></td>
<td>boolean</td>
<td>no</td>
<td>Whether or not this request is done via HTTPS</td>
</tr>
<tr>
<td><code>log_id</code></td>
<td>string</td>
<td>no</td>
<td>The ID to identify request in access and error log.</td>
</tr>
<tr class="odd">
<td><code>method</code></td>
<td>string</td>
<td>no</td>
</tr>
<tr>
<td><code>notes</code></td>
<td>table</td>
<td>yes</td>
<td>A list of notes that can be passed on from one module to another.</td>
</tr>
<tr class="odd">
<td><code>path_info</code></td>
<td>string</td>
<td>no</td>
<td>The PATH_INFO extracted from this request.</td>
</tr>
<tr>
<td><code>protocol</code></td>
<td>string</td>
<td>no</td>
</tr>
<tr class="odd">
<td><code>proxyreq</code></td>
<td>string</td>
<td>yes</td>
<td>Denotes whether this is a proxy request or not. This value is generally set in
</tr>
<tr>
<td><code>range</code></td>
<td>string</td>
<td>no</td>
<td>The contents of the <code>Range:</code> header.</td>
</tr>
<tr class="odd">
<td><code>subprocess_env</code></td>
<td>table</td>
<td>yes</td>
<td>The environment variables set for this request.</td>
</tr>
<tr>
<td><code>status</code></td>
<td>number</td>
<td>yes</td>
<td>The (current) HTTP return code for this request, f.x. <code>200</code> or <code>404</code>.</td>
</tr>
<tr class="odd">
<td><code>the_request</code></td>
<td>string</td>
<td>no</td>
</tr>
<tr>
<td><code>unparsed_uri</code></td>
<td>string</td>
<td>no</td>
<td>The unparsed URI of the request</td>
</tr>
<tr class="odd">
<td><code>uri</code></td>
<td>string</td>
<td>yes</td>
<td>The URI after it has been parsed by httpd</td>
</tr>
<tr>
<td><code>user</code></td>
<td>string</td>
<td>yes</td>
<td>If an authentication check has been made, this is set to the name of the authenticated user.</td>
</tr>
<tr class="odd">
<td><code>useragent_ip</code></td>
<td>string</td>
<td>no</td>
<td>The IP of the user agent making the request</td>
</tr>
</table>
<p>The request_rec has (at least) the following methods:</p>
<pre class="prettyprint lang-lua">
r:addoutputfilter(name|function) -- add an output filter
</pre>
<pre class="prettyprint lang-lua">
r:parseargs() -- returns a Lua table containing the request's query string arguments
</pre>
<pre class="prettyprint lang-lua">
r:parsebody() -- parse any POST data in the request and return it as a Lua table
</pre>
<pre class="prettyprint lang-lua">
r:puts("hello", " world", "!") -- print to response body
</pre>
<pre class="prettyprint lang-lua">
r:write("a single string") -- print to response body
</pre>
<pre class="prettyprint lang-lua">
r:escape_html("<html>test</html>") -- Escapes HTML code and returns the escaped result
</pre>
</dd>
</dl>
<div class="section">
<h2><a name="logging" id="logging">Logging Functions</a></h2>
<pre class="prettyprint lang-lua">
-- examples of logging messages<br />
r:trace1("This is a trace log message") -- trace1 through trace8 can be used <br />
r:debug("This is a debug log message")<br />
r:info("This is an info log message")<br />
r:notice("This is an notice log message")<br />
r:warn("This is an warn log message")<br />
r:err("This is an err log message")<br />
r:alert("This is an alert log message")<br />
r:crit("This is an crit log message")<br />
r:emerg("This is an emerg log message")<br />
</pre>
<div class="section">
<h2><a name="apache2" id="apache2">apache2 Package</a></h2>
<p>A package named <code>apache2</code> is available with (at least) the following contents.</p>
<dl>
<dd>internal constant OK. Handlers should return this if they've
handled the request.</dd>
<dd>internal constant DECLINED. Handlers should return this if
they are not going to handle the request.</dd>
<dd>internal constant DONE.</dd>
<dd>Apache HTTP server version string</dd>
<dd>HTTP status code</dd>
<dt>apache2.PROXYREQ_NONE, apache2.PROXYREQ_PROXY, apache2.PROXYREQ_REVERSE, apache2.PROXYREQ_RESPONSE</dt>
<dd>internal constants used by <code class="module"><a href="/mod/mod_proxy.html">mod_proxy</a></code></dd>
<dt>apache2.AUTHZ_DENIED, apache2.AUTHZ_GRANTED, apache2.AUTHZ_NEUTRAL, apache2.AUTHZ_GENERAL_ERROR, apache2.AUTHZ_DENIED_NO_USER</dt>
<dd>internal constants used by <code class="module"><a href="/mod/mod_authz_core.html">mod_authz_core</a></code></dd>
</dl>
<p>(Other HTTP status codes are not yet implemented.)</p>
</div>
<div class="directive-section"><h2><a name="LuaAuthzProvider" id="LuaAuthzProvider">LuaAuthzProvider</a> <a name="luaauthzprovider" id="luaauthzprovider">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Plug an authorization provider function into <code class="module"><a href="/mod/mod_authz_core.html">mod_authz_core</a></code>
</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaAuthzProvider provider_name /path/to/lua/script.lua function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.5.0 and later</td></tr>
</table>
<p>After a lua function has been registered as authorization provider, it can be used
with the <code class="directive"><a href="/mod/mod_authz_core.html#require">Require</a></code> directive:</p>
<pre class="prettyprint lang-config">
LuaAuthzProvider foo authz.lua authz_check_foo
<Location />
Require foo johndoe
</Location>
</pre>
<pre class="prettyprint lang-lua">
require "apache2"
function authz_check_foo(r, who)
if r.user ~= who then return apache2.AUTHZ_DENIED
return apache2.AUTHZ_GRANTED
end
</pre>
</div>
<div class="directive-section"><h2><a name="LuaCodeCache" id="LuaCodeCache">LuaCodeCache</a> <a name="luacodecache" id="luacodecache">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configure the compiled code cache.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaCodeCache stat|forever|never</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LuaCodeCache stat</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table><p>
Specify the behavior of the in-memory code cache. The default
is stat, which stats the top level script (not any included
ones) each time that file is needed, and reloads it if the
modified time indicates it is newer than the one it has
already loaded. The other values cause it to keep the file
cached forever (don't stat and replace) or to never cache the
file.</p>
<p>In general stat or forever is good for production, and stat or never
for development.</p>
<div class="example"><h3>Examples:</h3><pre class="prettyprint lang-config">
LuaCodeCache stat
LuaCodeCache forever
LuaCodeCache never
</pre>
</div>
</div>
<div class="directive-section"><h2><a name="LuaHookAccessChecker" id="LuaHookAccessChecker">LuaHookAccessChecker</a> <a name="luahookaccesschecker" id="luahookaccesschecker">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the access_checker phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookAccessChecker /path/to/lua/script.lua hook_function_name [early|late]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The optional third argument is supported in 2.3.15 and later</td></tr>
</table>
<p>Add your hook to the access_checker phase. An access checker
hook function usually returns OK, DECLINED, or HTTP_FORBIDDEN.</p>
<div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late"
control when this script runs relative to other modules.</p></div>
</div>
<div class="directive-section"><h2><a name="LuaHookAuthChecker" id="LuaHookAuthChecker">LuaHookAuthChecker</a> <a name="luahookauthchecker" id="luahookauthchecker">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the auth_checker phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookAuthChecker /path/to/lua/script.lua hook_function_name [early|late]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The optional third argument is supported in 2.3.15 and later</td></tr>
</table>
<p>Invoke a lua function in the auth_checker phase of processing
a request. This can be used to implement arbitrary authentication
and authorization checking. A very simple example:
</p>
<pre class="prettyprint lang-lua">
require 'apache2'
-- fake authcheck hook
-- If request has no auth info, set the response header and
-- return a 401 to ask the browser for basic auth info.
-- If request has auth info, don't actually look at it, just
-- pretend we got userid 'foo' and validated it.
-- Then check if the userid is 'foo' and accept the request.
function authcheck_hook(r)
-- look for auth info
auth = r.headers_in['Authorization']
if auth ~= nil then
-- fake the user
r.user = 'foo'
end
if r.user == nil then
r:debug("authcheck: user is nil, returning 401")
r.err_headers_out['WWW-Authenticate'] = 'Basic realm="WallyWorld"'
return 401
elseif r.user == "foo" then
r:debug('user foo: OK')
else
r:debug("authcheck: user='" .. r.user .. "'")
r.err_headers_out['WWW-Authenticate'] = 'Basic realm="WallyWorld"'
return 401
end
return apache2.OK
end
</pre>
<div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late"
control when this script runs relative to other modules.</p></div>
</div>
<div class="directive-section"><h2><a name="LuaHookCheckUserID" id="LuaHookCheckUserID">LuaHookCheckUserID</a> <a name="luahookcheckuserid" id="luahookcheckuserid">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the check_user_id phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookCheckUserID /path/to/lua/script.lua hook_function_name [early|late]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The optional third argument is supported in 2.3.15 and later</td></tr>
</table><p>...</p>
<div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late"
control when this script runs relative to other modules.</p></div>
</div>
<div class="directive-section"><h2><a name="LuaHookFixups" id="LuaHookFixups">LuaHookFixups</a> <a name="luahookfixups" id="luahookfixups">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the fixups phase of a request
processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookFixups /path/to/lua/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table>
<p>
Just like LuaHookTranslateName, but executed at the fixups phase
</p>
</div>
<div class="directive-section"><h2><a name="LuaHookInsertFilter" id="LuaHookInsertFilter">LuaHookInsertFilter</a> <a name="luahookinsertfilter" id="luahookinsertfilter">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the insert_filter phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookInsertFilter /path/to/lua/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table><p>Not Yet Implemented</p>
</div>
<div class="directive-section"><h2><a name="LuaHookMapToStorage" id="LuaHookMapToStorage">LuaHookMapToStorage</a> <a name="luahookmaptostorage" id="luahookmaptostorage">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the map_to_storage phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookMapToStorage /path/to/lua/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table>
<p>Like <code class="directive">LuaHookTranslateName</code> but executed at the
map-to-storage phase of a request. Modules like mod_cache run at this phase,
which makes for an interesting example on what to do here:</p>
<pre class="prettyprint lang-config">
</pre>
<pre class="prettyprint lang-lua">
require"apache2"
cached_files = {}
function read_file(filename)
local input = io.open(filename, "r")
if input then
local data = input:read("*a")
cached_files[filename] = data
file = cached_files[filename]
input:close()
end
return cached_files[filename]
end
function check_cache(r)
if r.filename:match("%.png$") then -- Only match PNG files
local file = cached_files[r.filename] -- Check cache entries
if not file then
file = read_file(r.filename) -- Read file into cache
end
if file then -- If file exists, write it out
r.status = 200
r:write(file)
r:info(("Sent %s to client from cache"):format(r.filename))
return apache2.DONE -- skip default handler for PNG files
end
end
return apache2.DECLINED -- If we had nothing to do, let others serve this.
end
</pre>
</div>
<div class="directive-section"><h2><a name="LuaHookTranslateName" id="LuaHookTranslateName">LuaHookTranslateName</a> <a name="luahooktranslatename" id="luahooktranslatename">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the translate name phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookTranslateName /path/to/lua/script.lua hook_function_name [early|late]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The optional third argument is supported in 2.3.15 and later</td></tr>
</table><p>
Add a hook (at APR_HOOK_MIDDLE) to the translate name phase of
request processing. The hook function receives a single
argument, the request_rec, and should return a status code,
which is either an HTTP error code, or the constants defined
in the apache2 module: apache2.OK, apache2.DECLINED, or
apache2.DONE. </p>
<p>For those new to hooks, basically each hook will be invoked
until one of them returns apache2.OK. If your hook doesn't
want to do the translation it should just return
apache2.DECLINED. If the request should stop processing, then
return apache2.DONE.</p>
<p>Example:</p>
<pre class="prettyprint lang-config">
</pre>
<pre class="prettyprint lang-lua">
require "apache2"
function silly_mapper(r)
if r.uri == "/" then
return apache2.OK
else
return apache2.DECLINED
end
end
</pre>
<div class="note"><h3>Context</h3><p>This directive is not valid in <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code>, <code class="directive"><a href="/mod/core.html#files"><Files></a></code>, or htaccess
context.</p></div>
<div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late"
control when this script runs relative to other modules.</p></div>
</div>
<div class="directive-section"><h2><a name="LuaHookTypeChecker" id="LuaHookTypeChecker">LuaHookTypeChecker</a> <a name="luahooktypechecker" id="luahooktypechecker">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the type_checker phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookTypeChecker /path/to/lua/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table><p>
This directive provides a hook for the type_checker phase of the request processing.
This phase is where requests are assigned a content type and a handler, and thus can
be used to modify the type and handler based on input:
</p>
<pre class="prettyprint lang-config">
</pre>
<pre class="prettyprint lang-lua">
function type_checker(r)
if r.uri:match("%.to_gif$") then -- match foo.png.to_gif
r.handler = "gifWizard" -- tell the gifWizard module to handle this
r.filename = r.uri:gsub("%.to_gif$", "") -- fix the filename requested
return apache2.OK
end
return apache2.DECLINED
end
</pre>
</div>
<div class="directive-section"><h2><a name="LuaInherit" id="LuaInherit">LuaInherit</a> <a name="luainherit" id="luainherit">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Controls how parent configuration sections are merged into children</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaInherit none|parent-first|parent-last</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LuaInherit parent-first</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.4.0 and later</td></tr>
</table><p>By default, if LuaHook* directives are used in overlapping
Directory or Location configuration sections, the scripts defined in the
more specific section are run <em>after</em> those defined in the more
generic section (LuaInherit parent-first). You can reverse this order, or
make the parent context not apply at all.</p>
<p> In previous 2.3.x releases, the default was effectively to ignore LuaHook*
directives from parent configuration sections.</p>
</div>
<div class="directive-section"><h2><a name="LuaMapHandler" id="LuaMapHandler">LuaMapHandler</a> <a name="luamaphandler" id="luamaphandler">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Map a path to a lua handler</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaMapHandler uri-pattern /path/to/lua/script.lua [function-name]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table>
<p>This directive matches a uri pattern to invoke a specific
handler function in a specific file. It uses PCRE regular
expressions to match the uri, and supports interpolating
match groups into both the file path and the function name
be careful writing your regular expressions to avoid security
issues.</p>
<div class="example"><h3>Examples:</h3><pre class="prettyprint lang-config">
LuaMapHandler /(\w+)/(\w+) /scripts/$1.lua handle_$2
</pre>
</div>
to the file /scripts/photos.lua and invoke the
handler function handle_show on the lua vm after
loading that file.</p>
<pre class="prettyprint lang-config">
LuaMapHandler /bingo /scripts/wombat.lua
</pre>
<p>This would invoke the "handle" function, which
is the default if no specific function name is
provided.</p>
</div>
<div class="directive-section"><h2><a name="LuaPackageCPath" id="LuaPackageCPath">LuaPackageCPath</a> <a name="luapackagecpath" id="luapackagecpath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Add a directory to lua's package.cpath</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaPackageCPath /path/to/include/?.soa</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table>
<p>Add a path to lua's shared library search path. Follows the same
conventions as lua. This just munges the package.cpath in the
lua vms.</p>
</div>
<div class="directive-section"><h2><a name="LuaPackagePath" id="LuaPackagePath">LuaPackagePath</a> <a name="luapackagepath" id="luapackagepath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Add a directory to lua's package.path</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaPackagePath /path/to/include/?.lua</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table><p>Add a path to lua's module search path. Follows the same
conventions as lua. This just munges the package.path in the
lua vms.</p>
<div class="example"><h3>Examples:</h3><pre class="prettyprint lang-config">
</pre>
</div>
</div>
<div class="directive-section"><h2><a name="LuaQuickHandler" id="LuaQuickHandler">LuaQuickHandler</a> <a name="luaquickhandler" id="luaquickhandler">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the quick handler of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaQuickHandler /path/to/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
</table><p>...</p>
<div class="note"><h3>Context</h3><p>This directive is not valid in <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code>, <code class="directive"><a href="/mod/core.html#files"><Files></a></code>, or htaccess
context.</p></div>
</div>
<div class="directive-section"><h2><a name="LuaRoot" id="LuaRoot">LuaRoot</a> <a name="luaroot" id="luaroot">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Specify the base path for resolving relative paths for mod_lua directives</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaRoot /path/to/a/directory</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table>
<p>Specify the base path which will be used to evaluate all
relative paths within mod_lua. If not specified they
will be resolved relative to the current working directory,
which may not always work well for a server.</p>
</div>
<div class="directive-section"><h2><a name="LuaScope" id="LuaScope">LuaScope</a> <a name="luascope" id="luascope">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>One of once, request, conn, thread -- default is once</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaScope once|request|conn|thread|server [min] [max]</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LuaScope once</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
</table>
<p>Specify the lifecycle scope of the Lua interpreter which will
be used by handlers in this "Directory." The default is "once"</p>
<dl>
<dt>once:</dt> <dd>use the interpreter once and throw it away.</dd>
<dt>request:</dt> <dd>use the interpreter to handle anything based on
the same file within this request, which is also
request scoped.</dd>
<dt>conn:</dt> <dd>Same as request but attached to the connection_rec</dd>
<dt>thread:</dt> <dd>Use the interpreter for the lifetime of the thread
handling the request (only available with threaded MPMs).</dd>
<dt>server:</dt> <dd>This one is different than others because the
server scope is quite long lived, and multiple threads
will have the same server_rec. To accommodate this
server scoped interpreter are stored in an apr
resource list. The <code>min</code> and <code>max</code> arguments
specify the minimum and maximum number of Lua states to keep in the
pool.</dd>
</dl>
<p>
Generally speaking, the <code>thread</code> and <code>server</code> scopes
execute roughly 2-3 times faster than the rest, because they don't have to
spawn new Lua states on every request (especially with the event MPM, as
even keepalive requests will use a new thread for each request). If you are
satisfied that your scripts will not have problems reusing a state, then
the <code>thread</code> or <code>server</code> scopes should be used for
maximum performance. While the <code>thread</code> scope will provide the
fastest responses, the <code>server</code> scope will use less memory, as
states are pooled, allowing f.x. 1000 threads to share only 100 Lua states,
thus using only 10% of the memory requried by the <code>thread</code> scope.
</p>
</div>
</div>
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