1<?xml version="1.0" encoding="ISO-8859-1"?> 2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 3<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!-- 4 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 5 This file is generated from xml source: DO NOT EDIT 6 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 7 --> 8<title>mod_lua - Apache HTTP Server</title> 9<link href="/style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> 10<link href="/style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> 11<link href="/style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /><link rel="stylesheet" type="text/css" href="/style/css/prettify.css" /> 12<script src="/style/scripts/prettify.min.js" type="text/javascript"> 13</script> 14 15<link href="/images/favicon.ico" rel="shortcut icon" /></head> 16<body> 17<div id="page-header"> 18<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> 19<p class="apache">Apache HTTP Server Version 2.4</p> 20<img alt="" src="/images/feather.gif" /></div> 21<div class="up"><a href="./"><img title="<-" alt="<-" src="/images/left.gif" /></a></div> 22<div id="path"> 23<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 2.4</a> > <a href="./">Modules</a></div> 24<div id="page-content"> 25<div id="preamble"><h1>Apache Module mod_lua</h1> 26<div class="toplang"> 27<p><span>Available Languages: </span><a href="/en/mod/mod_lua.html" title="English"> en </a> | 28<a href="/fr/mod/mod_lua.html" hreflang="fr" rel="alternate" title="Fran�ais"> fr </a></p> 29</div> 30<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Provides Lua hooks into various portions of the httpd 31request processing</td></tr> 32<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 33<tr><th><a href="module-dict.html#ModuleIdentifier">Module�Identifier:</a></th><td>lua_module</td></tr> 34<tr><th><a href="module-dict.html#SourceFile">Source�File:</a></th><td>mod_lua.c</td></tr> 35<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>2.3 and later</td></tr></table> 36<h3>Summary</h3> 37 38<p>This module allows the server to be extended with scripts written in the 39Lua programming language. The extension points (hooks) available with 40<code class="module"><a href="/mod/mod_lua.html">mod_lua</a></code> include many of the hooks available to 41natively compiled Apache HTTP Server modules, such as mapping requests to 42files, generating dynamic responses, access control, authentication, and 43authorization</p> 44 45<p>More information on the Lua programming language can be found at the 46<a href="http://www.lua.org/">the Lua website</a>.</p> 47 48<div class="note"><code>mod_lua</code> is still in experimental state. 49Until it is declared stable, usage and behavior may change 50at any time, even between stable releases of the 2.4.x series. 51Be sure to check the CHANGES file before upgrading.</div> 52 53<div class="warning"><h3>Warning</h3> 54<p>This module holds a great deal of power over httpd, which is both a 55strength and a potential security risk. It is <strong>not</strong> recommended 56that you use this module on a server that is shared with users you do not 57trust, as it can be abused to change the internal workings of httpd.</p> 58</div> 59 60</div> 61<div id="quickview"><h3 class="directives">Directives</h3> 62<ul id="toc"> 63<li><img alt="" src="/images/down.gif" /> <a href="#luaauthzprovider">LuaAuthzProvider</a></li> 64<li><img alt="" src="/images/down.gif" /> <a href="#luacodecache">LuaCodeCache</a></li> 65<li><img alt="" src="/images/down.gif" /> <a href="#luahookaccesschecker">LuaHookAccessChecker</a></li> 66<li><img alt="" src="/images/down.gif" /> <a href="#luahookauthchecker">LuaHookAuthChecker</a></li> 67<li><img alt="" src="/images/down.gif" /> <a href="#luahookcheckuserid">LuaHookCheckUserID</a></li> 68<li><img alt="" src="/images/down.gif" /> <a href="#luahookfixups">LuaHookFixups</a></li> 69<li><img alt="" src="/images/down.gif" /> <a href="#luahookinsertfilter">LuaHookInsertFilter</a></li> 70<li><img alt="" src="/images/down.gif" /> <a href="#luahooklog">LuaHookLog</a></li> 71<li><img alt="" src="/images/down.gif" /> <a href="#luahookmaptostorage">LuaHookMapToStorage</a></li> 72<li><img alt="" src="/images/down.gif" /> <a href="#luahooktranslatename">LuaHookTranslateName</a></li> 73<li><img alt="" src="/images/down.gif" /> <a href="#luahooktypechecker">LuaHookTypeChecker</a></li> 74<li><img alt="" src="/images/down.gif" /> <a href="#luainherit">LuaInherit</a></li> 75<li><img alt="" src="/images/down.gif" /> <a href="#luainputfilter">LuaInputFilter</a></li> 76<li><img alt="" src="/images/down.gif" /> <a href="#luamaphandler">LuaMapHandler</a></li> 77<li><img alt="" src="/images/down.gif" /> <a href="#luaoutputfilter">LuaOutputFilter</a></li> 78<li><img alt="" src="/images/down.gif" /> <a href="#luapackagecpath">LuaPackageCPath</a></li> 79<li><img alt="" src="/images/down.gif" /> <a href="#luapackagepath">LuaPackagePath</a></li> 80<li><img alt="" src="/images/down.gif" /> <a href="#luaquickhandler">LuaQuickHandler</a></li> 81<li><img alt="" src="/images/down.gif" /> <a href="#luaroot">LuaRoot</a></li> 82<li><img alt="" src="/images/down.gif" /> <a href="#luascope">LuaScope</a></li> 83</ul> 84<h3>Topics</h3> 85<ul id="topics"> 86<li><img alt="" src="/images/down.gif" /> <a href="#basicconf">Basic Configuration</a></li> 87<li><img alt="" src="/images/down.gif" /> <a href="#writinghandlers">Writing Handlers</a></li> 88<li><img alt="" src="/images/down.gif" /> <a href="#writingauthzproviders">Writing Authorization Providers</a></li> 89<li><img alt="" src="/images/down.gif" /> <a href="#writinghooks">Writing Hooks</a></li> 90<li><img alt="" src="/images/down.gif" /> <a href="#datastructures">Data Structures</a></li> 91<li><img alt="" src="/images/down.gif" /> <a href="#functions">Built in functions</a></li> 92<li><img alt="" src="/images/down.gif" /> <a href="#logging">Logging Functions</a></li> 93<li><img alt="" src="/images/down.gif" /> <a href="#apache2">apache2 Package</a></li> 94<li><img alt="" src="/images/down.gif" /> <a href="#modifying_buckets">Modifying contents with Lua filters</a></li> 95<li><img alt="" src="/images/down.gif" /> <a href="#databases">Database connectivity</a></li> 96</ul><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div> 97<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 98<div class="section"> 99<h2><a name="basicconf" id="basicconf">Basic Configuration</a></h2> 100 101<p>The basic module loading directive is</p> 102 103<pre class="prettyprint lang-config">LoadModule lua_module modules/mod_lua.so</pre> 104 105 106<p> 107<code>mod_lua</code> provides a handler named <code>lua-script</code>, 108which can be used with a <code class="directive"><a href="/mod/core.html#sethandler">SetHandler</a></code> or 109<code class="directive"><a href="/mod/mod_mime.html#addhandler">AddHandler</a></code> directive:</p> 110 111<pre class="prettyprint lang-config"><Files *.lua> 112 SetHandler lua-script 113</Files></pre> 114 115 116<p> 117This will cause <code>mod_lua</code> to handle requests for files 118ending in <code>.lua</code> by invoking that file's 119<code>handle</code> function. 120</p> 121 122<p>For more flexibility, see <code class="directive">LuaMapHandler</code>. 123</p> 124 125</div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 126<div class="section"> 127<h2><a name="writinghandlers" id="writinghandlers">Writing Handlers</a></h2> 128<p> In the Apache HTTP Server API, the handler is a specific kind of hook 129responsible for generating the response. Examples of modules that include a 130handler 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>, 131and <code class="module"><a href="/mod/mod_status.html">mod_status</a></code>.</p> 132 133<p><code>mod_lua</code> always looks to invoke a Lua function for the handler, rather than 134just evaluating a script body CGI style. A handler function looks 135something like this:</p> 136 137 138<pre class="prettyprint lang-lua"> 139<strong>example.lua</strong><br /> 140-- example handler 141 142require "string" 143 144--[[ 145 This is the default method name for Lua handlers, see the optional 146 function-name in the LuaMapHandler directive to choose a different 147 entry point. 148--]] 149function handle(r) 150 r.content_type = "text/plain" 151 152 if r.method == 'GET' then 153 r:puts("Hello Lua World!\n") 154 for k, v in pairs( r:parseargs() ) do 155 r:puts( string.format("%s: %s\n", k, v) ) 156 end 157 elseif r.method == 'POST' then 158 r:puts("Hello Lua World!\n") 159 for k, v in pairs( r:parsebody() ) do 160 r:puts( string.format("%s: %s\n", k, v) ) 161 end 162 elseif r.method == 'PUT' then 163-- use our own Error contents 164 r:puts("Unsupported HTTP method " .. r.method) 165 r.status = 405 166 return apache2.ok 167 else 168-- use the ErrorDocument 169 return 501 170 end 171 return apache2.OK 172end</pre> 173 174 175<p> 176This handler function just prints out the uri or form encoded 177arguments to a plaintext page. 178</p> 179 180<p> 181This means (and in fact encourages) that you can have multiple 182handlers (or hooks, or filters) in the same script. 183</p> 184 185</div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 186<div class="section"> 187<h2><a name="writingauthzproviders" id="writingauthzproviders">Writing Authorization Providers</a></h2> 188 189 190<p><code class="module"><a href="/mod/mod_authz_core.html">mod_authz_core</a></code> provides a high-level interface to 191authorization that is much easier to use than using into the relevant 192hooks directly. The first argument to the 193<code class="directive"><a href="/mod/mod_authz_core.html#require">Require</a></code> directive gives 194the name of the responsible authorization provider. For any 195<code class="directive"><a href="/mod/mod_authz_core.html#require">Require</a></code> line, 196<code class="module"><a href="/mod/mod_authz_core.html">mod_authz_core</a></code> will call the authorization provider 197of the given name, passing the rest of the line as parameters. The 198provider will then check authorization and pass the result as return 199value.</p> 200 201<p>The authz provider is normally called before authentication. If it needs to 202know the authenticated user name (or if the user will be authenticated at 203all), the provider must return <code>apache2.AUTHZ_DENIED_NO_USER</code>. 204This will cause authentication to proceed and the authz provider to be 205called a second time.</p> 206 207<p>The following authz provider function takes two arguments, one ip 208address and one user name. It will allow access from the given ip address 209without authentication, or if the authenticated user matches the second 210argument:</p> 211 212<pre class="prettyprint lang-lua"> 213<strong>authz_provider.lua</strong><br /> 214 215require 'apache2' 216 217function authz_check_foo(r, ip, user) 218 if r.useragent_ip == ip then 219 return apache2.AUTHZ_GRANTED 220 elseif r.user == nil then 221 return apache2.AUTHZ_DENIED_NO_USER 222 elseif r.user == user then 223 return apache2.AUTHZ_GRANTED 224 else 225 return apache2.AUTHZ_DENIED 226 end 227end</pre> 228 229 230<p>The following configuration registers this function as provider 231<code>foo</code> and configures it for URL <code>/</code>:</p> 232<pre class="prettyprint lang-config">LuaAuthzProvider foo authz_provider.lua authz_check_foo 233<Location /> 234 Require foo 10.1.2.3 john_doe 235</Location></pre> 236 237 238</div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 239<div class="section"> 240<h2><a name="writinghooks" id="writinghooks">Writing Hooks</a></h2> 241 242<p>Hook functions are how modules (and Lua scripts) participate in the 243processing of requests. Each type of hook exposed by the server exists for 244a specific purpose, such as mapping requests to the file system, 245performing access control, or setting mime types:</p> 246 247<table class="bordered"><tr class="header"> 248 <th>Hook phase</th> 249 <th>mod_lua directive</th> 250 <th>Description</th> 251 </tr> 252<tr> 253 <td>Quick handler</td> 254 <td><code class="directive"><a href="#luaquickhandler">LuaQuickHandler</a></code></td> 255 <td>This is the first hook that will be called after a request has 256 been mapped to a host or virtual host</td> 257 </tr> 258<tr class="odd"> 259 <td>Translate name</td> 260 <td><code class="directive"><a href="#luahooktranslatename">LuaHookTranslateName</a></code></td> 261 <td>This phase translates the requested URI into a filename on the 262 system. Modules such as <code class="module"><a href="/mod/mod_alias.html">mod_alias</a></code> and 263 <code class="module"><a href="/mod/mod_rewrite.html">mod_rewrite</a></code> operate in this phase.</td> 264 </tr> 265<tr> 266 <td>Map to storage</td> 267 <td><code class="directive"><a href="#luahookmaptostorage">LuaHookMapToStorage</a></code></td> 268 <td>This phase maps files to their physical, cached or external/proxied storage. 269 It can be used by proxy or caching modules</td> 270 </tr> 271<tr class="odd"> 272 <td>Check Access</td> 273 <td><code class="directive"><a href="#luahookaccesschecker">LuaHookAccessChecker</a></code></td> 274 <td>This phase checks whether a client has access to a resource. This 275 phase is run before the user is authenticated, so beware. 276 </td> 277 </tr> 278<tr> 279 <td>Check User ID</td> 280 <td><code class="directive"><a href="#luahookcheckuserid">LuaHookCheckUserID</a></code></td> 281 <td>This phase it used to check the negotiated user ID</td> 282 </tr> 283<tr class="odd"> 284 <td>Check Authorization</td> 285 <td><code class="directive"><a href="#luahookauthchecker">LuaHookAuthChecker</a></code> or 286 <code class="directive"><a href="#luaauthzprovider">LuaAuthzProvider</a></code></td> 287 <td>This phase authorizes a user based on the negotiated credentials, such as 288 user ID, client certificate etc. 289 </td> 290 </tr> 291<tr> 292 <td>Check Type</td> 293 <td><code class="directive"><a href="#luahooktypechecker">LuaHookTypeChecker</a></code></td> 294 <td>This phase checks the requested file and assigns a content type and 295 a handler to it</td> 296 </tr> 297<tr class="odd"> 298 <td>Fixups</td> 299 <td><code class="directive"><a href="#luahookfixups">LuaHookFixups</a></code></td> 300 <td>This is the final "fix anything" phase before the content handlers 301 are run. Any last-minute changes to the request should be made here.</td> 302 </tr> 303<tr> 304 <td>Content handler</td> 305 <td>fx. <code>.lua</code> files or through <code class="directive"><a href="#luamaphandler">LuaMapHandler</a></code></td> 306 <td>This is where the content is handled. Files are read, parsed, some are run, 307 and the result is sent to the client</td> 308 </tr> 309<tr class="odd"> 310 <td>Logging</td> 311 <td><code class="directive"><a href="#luahooklog">LuaHookLog</a></code></td> 312 <td>Once a request has been handled, it enters several logging phases, 313 which logs the request in either the error or access log. Mod_lua 314 is able to hook into the start of this and control logging output.</td> 315 </tr> 316</table> 317 318<p>Hook functions are passed the request object as their only argument 319(except for LuaAuthzProvider, which also gets passed the arguments from 320the Require directive). 321They can return any value, depending on the hook, but most commonly 322they'll return OK, DONE, or DECLINED, which you can write in Lua as 323<code>apache2.OK</code>, <code>apache2.DONE</code>, or 324<code>apache2.DECLINED</code>, or else an HTTP status code.</p> 325 326 327<pre class="prettyprint lang-lua"> 328<strong>translate_name.lua</strong><br /> 329-- example hook that rewrites the URI to a filesystem path. 330 331require 'apache2' 332 333function translate_name(r) 334 if r.uri == "/translate-name" then 335 r.filename = r.document_root .. "/find_me.txt" 336 return apache2.OK 337 end 338 -- we don't care about this URL, give another module a chance 339 return apache2.DECLINED 340end</pre> 341 342 343 344<pre class="prettyprint lang-lua"> 345<strong>translate_name2.lua</strong><br /> 346--[[ example hook that rewrites one URI to another URI. It returns a 347 apache2.DECLINED to give other URL mappers a chance to work on the 348 substitution, including the core translate_name hook which maps based 349 on the DocumentRoot. 350 351 Note: Use the early/late flags in the directive to make it run before 352 or after mod_alias. 353--]] 354 355require 'apache2' 356 357function translate_name(r) 358 if r.uri == "/translate-name" then 359 r.uri = "/find_me.txt" 360 return apache2.DECLINED 361 end 362 return apache2.DECLINED 363end</pre> 364 365</div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 366<div class="section"> 367<h2><a name="datastructures" id="datastructures">Data Structures</a></h2> 368 369<dl> 370<dt>request_rec</dt> 371 <dd> 372 <p>The request_rec is mapped in as a userdata. It has a metatable 373 which lets you do useful things with it. For the most part it 374 has the same fields as the request_rec struct, many of which are writable as 375 well as readable. (The table fields' content can be changed, but the 376 fields themselves cannot be set to different tables.)</p> 377 378 <table class="bordered"><tr class="header"> 379 <th><strong>Name</strong></th> 380 <th><strong>Lua type</strong></th> 381 <th><strong>Writable</strong></th> 382 <th><strong>Description</strong></th> 383 </tr> 384<tr> 385 <td><code>allowoverrides</code></td> 386 <td>string</td> 387 <td>no</td> 388 <td>The AllowOverride options applied to the current request.</td> 389 </tr> 390<tr class="odd"> 391 <td><code>ap_auth_type</code></td> 392 <td>string</td> 393 <td>no</td> 394 <td>If an authentication check was made, this is set to the type 395 of authentication (f.x. <code>basic</code>)</td> 396 </tr> 397<tr> 398 <td><code>args</code></td> 399 <td>string</td> 400 <td>yes</td> 401 <td>The query string arguments extracted from the request 402 (f.x. <code>foo=bar&name=johnsmith</code>)</td> 403 </tr> 404<tr class="odd"> 405 <td><code>assbackwards</code></td> 406 <td>boolean</td> 407 <td>no</td> 408 <td>Set to true if this is an HTTP/0.9 style request 409 (e.g. <code>GET /foo</code> (with no headers) )</td> 410 </tr> 411<tr> 412 <td><code>auth_name</code></td> 413 <td>string</td> 414 <td>no</td> 415 <td>The realm name used for authorization (if applicable).</td> 416 </tr> 417<tr class="odd"> 418 <td><code>banner</code></td> 419 <td>string</td> 420 <td>no</td> 421 <td>The server banner, f.x. <code>Apache HTTP Server/2.4.3 openssl/0.9.8c</code></td> 422 </tr> 423<tr> 424 <td><code>basic_auth_pw</code></td> 425 <td>string</td> 426 <td>no</td> 427 <td>The basic auth password sent with this request, if any</td> 428 </tr> 429<tr class="odd"> 430 <td><code>canonical_filename</code></td> 431 <td>string</td> 432 <td>no</td> 433 <td>The canonical filename of the request</td> 434 </tr> 435<tr> 436 <td><code>content_encoding</code></td> 437 <td>string</td> 438 <td>no</td> 439 <td>The content encoding of the current request</td> 440 </tr> 441<tr class="odd"> 442 <td><code>content_type</code></td> 443 <td>string</td> 444 <td>yes</td> 445 <td>The content type of the current request, as determined in the 446 type_check phase (f.x. <code>image/gif</code> or <code>text/html</code>)</td> 447 </tr> 448<tr> 449 <td><code>context_prefix</code></td> 450 <td>string</td> 451 <td>no</td> 452 <td /> 453 </tr> 454<tr class="odd"> 455 <td><code>context_document_root</code></td> 456 <td>string</td> 457 <td>no</td> 458 <td /> 459 </tr> 460<tr> 461 <td><code>document_root</code></td> 462 <td>string</td> 463 <td>no</td> 464 <td>The document root of the host</td> 465 </tr> 466<tr class="odd"> 467 <td><code>err_headers_out</code></td> 468 <td>table</td> 469 <td>no</td> 470 <td>MIME header environment for the response, printed even on errors and 471 persist across internal redirects</td> 472 </tr> 473<tr> 474 <td><code>filename</code></td> 475 <td>string</td> 476 <td>yes</td> 477 <td>The file name that the request maps to, f.x. /www/example.com/foo.txt. This can be 478 changed in the translate-name or map-to-storage phases of a request to allow the 479 default handler (or script handlers) to serve a different file than what was requested.</td> 480 </tr> 481<tr class="odd"> 482 <td><code>handler</code></td> 483 <td>string</td> 484 <td>yes</td> 485 <td>The name of the <a href="/handler.html">handler</a> that should serve this request, f.x. 486 <code>lua-script</code> if it is to be served by mod_lua. This is typically set by the 487 <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> 488 directives, but could also be set via mod_lua to allow another handler to serve up a specific request 489 that would otherwise not be served by it. 490 </td> 491 </tr> 492<tr> 493 <td><code>headers_in</code></td> 494 <td>table</td> 495 <td>yes</td> 496 <td>MIME header environment from the request. This contains headers such as <code>Host, 497 User-Agent, Referer</code> and so on.</td> 498 </tr> 499<tr class="odd"> 500 <td><code>headers_out</code></td> 501 <td>table</td> 502 <td>yes</td> 503 <td>MIME header environment for the response.</td> 504 </tr> 505<tr> 506 <td><code>hostname</code></td> 507 <td>string</td> 508 <td>no</td> 509 <td>The host name, as set by the <code>Host:</code> header or by a full URI.</td> 510 </tr> 511<tr class="odd"> 512 <td><code>is_https</code></td> 513 <td>boolean</td> 514 <td>no</td> 515 <td>Whether or not this request is done via HTTPS</td> 516 </tr> 517<tr> 518 <td><code>is_initial_req</code></td> 519 <td>boolean</td> 520 <td>no</td> 521 <td>Whether this request is the initial request or a sub-request</td> 522 </tr> 523<tr class="odd"> 524 <td><code>limit_req_body</code></td> 525 <td>number</td> 526 <td>no</td> 527 <td>The size limit of the request body for this request, or 0 if no limit.</td> 528 </tr> 529<tr> 530 <td><code>log_id</code></td> 531 <td>string</td> 532 <td>no</td> 533 <td>The ID to identify request in access and error log.</td> 534 </tr> 535<tr class="odd"> 536 <td><code>method</code></td> 537 <td>string</td> 538 <td>no</td> 539 <td>The request method, f.x. <code>GET</code> or <code>POST</code>.</td> 540 </tr> 541<tr> 542 <td><code>notes</code></td> 543 <td>table</td> 544 <td>yes</td> 545 <td>A list of notes that can be passed on from one module to another.</td> 546 </tr> 547<tr class="odd"> 548 <td><code>options</code></td> 549 <td>string</td> 550 <td>no</td> 551 <td>The Options directive applied to the current request.</td> 552 </tr> 553<tr> 554 <td><code>path_info</code></td> 555 <td>string</td> 556 <td>no</td> 557 <td>The PATH_INFO extracted from this request.</td> 558 </tr> 559<tr class="odd"> 560 <td><code>port</code></td> 561 <td>number</td> 562 <td>no</td> 563 <td>The server port used by the request.</td> 564 </tr> 565<tr> 566 <td><code>protocol</code></td> 567 <td>string</td> 568 <td>no</td> 569 <td>The protocol used, f.x. <code>HTTP/1.1</code></td> 570 </tr> 571<tr class="odd"> 572 <td><code>proxyreq</code></td> 573 <td>string</td> 574 <td>yes</td> 575 <td>Denotes whether this is a proxy request or not. This value is generally set in 576 the post_read_request/translate_name phase of a request.</td> 577 </tr> 578<tr> 579 <td><code>range</code></td> 580 <td>string</td> 581 <td>no</td> 582 <td>The contents of the <code>Range:</code> header.</td> 583 </tr> 584<tr class="odd"> 585 <td><code>remaining</code></td> 586 <td>number</td> 587 <td>no</td> 588 <td>The number of bytes remaining to be read from the request body.</td> 589 </tr> 590<tr> 591 <td><code>server_built</code></td> 592 <td>string</td> 593 <td>no</td> 594 <td>The time the server executable was built.</td> 595 </tr> 596<tr class="odd"> 597 <td><code>server_name</code></td> 598 <td>string</td> 599 <td>no</td> 600 <td>The server name for this request.</td> 601 </tr> 602<tr> 603 <td><code>some_auth_required</code></td> 604 <td>boolean</td> 605 <td>no</td> 606 <td>Whether some authorization is/was required for this request.</td> 607 </tr> 608<tr class="odd"> 609 <td><code>subprocess_env</code></td> 610 <td>table</td> 611 <td>yes</td> 612 <td>The environment variables set for this request.</td> 613 </tr> 614<tr> 615 <td><code>started</code></td> 616 <td>number</td> 617 <td>no</td> 618 <td>The time the server was (re)started, in seconds since the epoch (Jan 1st, 1970)</td> 619 </tr> 620<tr class="odd"> 621 <td><code>status</code></td> 622 <td>number</td> 623 <td>yes</td> 624 <td>The (current) HTTP return code for this request, f.x. <code>200</code> or <code>404</code>.</td> 625 </tr> 626<tr> 627 <td><code>the_request</code></td> 628 <td>string</td> 629 <td>no</td> 630 <td>The request string as sent by the client, f.x. <code>GET /foo/bar HTTP/1.1</code>.</td> 631 </tr> 632<tr class="odd"> 633 <td><code>unparsed_uri</code></td> 634 <td>string</td> 635 <td>no</td> 636 <td>The unparsed URI of the request</td> 637 </tr> 638<tr> 639 <td><code>uri</code></td> 640 <td>string</td> 641 <td>yes</td> 642 <td>The URI after it has been parsed by httpd</td> 643 </tr> 644<tr class="odd"> 645 <td><code>user</code></td> 646 <td>string</td> 647 <td>yes</td> 648 <td>If an authentication check has been made, this is set to the name of the authenticated user.</td> 649 </tr> 650<tr> 651 <td><code>useragent_ip</code></td> 652 <td>string</td> 653 <td>no</td> 654 <td>The IP of the user agent making the request</td> 655 </tr> 656</table> 657 </dd> 658 </dl> 659</div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 660<div class="section"> 661<h2><a name="functions" id="functions">Built in functions</a></h2> 662 663<p>The request_rec object has (at least) the following methods:</p> 664 665<pre class="prettyprint lang-lua">r:flush() -- flushes the output buffer. 666 -- Returns true if the flush was successful, false otherwise. 667 668while we_have_stuff_to_send do 669 r:puts("Bla bla bla\n") -- print something to client 670 r:flush() -- flush the buffer (send to client) 671 r.usleep(500000) -- fake processing time for 0.5 sec. and repeat 672end</pre> 673 674 675<pre class="prettyprint lang-lua">r:addoutputfilter(name|function) -- add an output filter: 676 677r:addoutputfilter("fooFilter") -- add the fooFilter to the output stream</pre> 678 679 680<pre class="prettyprint lang-lua">r:sendfile(filename) -- sends an entire file to the client, using sendfile if supported by the current platform: 681 682if use_sendfile_thing then 683 r:sendfile("/var/www/large_file.img") 684end</pre> 685 686 687<pre class="prettyprint lang-lua">r:parseargs() -- returns two tables; one standard key/value table for regular GET data, 688 -- and one for multi-value data (fx. foo=1&foo=2&foo=3): 689 690local GET, GETMULTI = r:parseargs() 691r:puts("Your name is: " .. GET['name'] or "Unknown")</pre> 692 693 694<pre class="prettyprint lang-lua">r:parsebody([sizeLimit]) -- parse the request body as a POST and return two lua tables, 695 -- just like r:parseargs(). 696 -- An optional number may be passed to specify the maximum number 697 -- of bytes to parse. Default is 8192 bytes: 698 699local POST, POSTMULTI = r:parsebody(1024*1024) 700r:puts("Your name is: " .. POST['name'] or "Unknown")</pre> 701 702 703<pre class="prettyprint lang-lua">r:puts("hello", " world", "!") -- print to response body, self explanatory</pre> 704 705 706<pre class="prettyprint lang-lua">r:write("a single string") -- print to response body, self explanatory</pre> 707 708 709<pre class="prettyprint lang-lua">r:escape_html("<html>test</html>") -- Escapes HTML code and returns the escaped result</pre> 710 711 712<pre class="prettyprint lang-lua">r:base64_encode(string) -- Encodes a string using the Base64 encoding standard: 713 714local encoded = r:base64_encode("This is a test") -- returns VGhpcyBpcyBhIHRlc3Q=</pre> 715 716 717<pre class="prettyprint lang-lua">r:base64_decode(string) -- Decodes a Base64-encoded string: 718 719local decoded = r:base64_decode("VGhpcyBpcyBhIHRlc3Q=") -- returns 'This is a test'</pre> 720 721 722<pre class="prettyprint lang-lua">r:md5(string) -- Calculates and returns the MD5 digest of a string (binary safe): 723 724local hash = r:md5("This is a test") -- returns ce114e4501d2f4e2dcea3e17b546f339</pre> 725 726 727<pre class="prettyprint lang-lua">r:sha1(string) -- Calculates and returns the SHA1 digest of a string (binary safe): 728 729local hash = r:sha1("This is a test") -- returns a54d88e06612d820bc3be72877c74f257b561b19</pre> 730 731 732<pre class="prettyprint lang-lua">r:escape(string) -- URL-Escapes a string: 733 734local url = "http://foo.bar/1 2 3 & 4 + 5" 735local escaped = r:escape(url) -- returns 'http%3a%2f%2ffoo.bar%2f1+2+3+%26+4+%2b+5'</pre> 736 737 738<pre class="prettyprint lang-lua">r:unescape(string) -- Unescapes an URL-escaped string: 739 740local url = "http%3a%2f%2ffoo.bar%2f1+2+3+%26+4+%2b+5" 741local unescaped = r:unescape(url) -- returns 'http://foo.bar/1 2 3 & 4 + 5'</pre> 742 743 744<pre class="prettyprint lang-lua">r:construct_url(string) -- Constructs an URL from an URI 745 746local url = r:construct_url(r.uri)</pre> 747 748 749<pre class="prettyprint lang-lua">r.mpm_query(number) -- Queries the server for MPM information using ap_mpm_query: 750 751local mpm = r.mpm_query(14) 752if mpm == 1 then 753 r:puts("This server uses the Event MPM") 754end</pre> 755 756 757<pre class="prettyprint lang-lua">r:expr(string) -- Evaluates an <a href="/expr.html">expr</a> string. 758 759if r:expr("%{HTTP_HOST} =~ /^www/") then 760 r:puts("This host name starts with www") 761end</pre> 762 763 764<pre class="prettyprint lang-lua">r:scoreboard_process(a) -- Queries the server for information about the process at position <code>a</code>: 765 766local process = r:scoreboard_process(1) 767r:puts("Server 1 has PID " .. process.pid)</pre> 768 769 770<pre class="prettyprint lang-lua">r:scoreboard_worker(a, b) -- Queries for information about the worker thread, <code>b</code>, in process <code>a</code>: 771 772local thread = r:scoreboard_worker(1, 1) 773r:puts("Server 1's thread 1 has thread ID " .. thread.tid .. " and is in " .. thread.status .. " status")</pre> 774 775 776 777<pre class="prettyprint lang-lua">r:clock() -- Returns the current time with microsecond precision</pre> 778 779 780<pre class="prettyprint lang-lua">r:requestbody(filename) -- Reads and returns the request body of a request. 781 -- If 'filename' is specified, it instead saves the 782 -- contents to that file: 783 784local input = r:requestbody() 785r:puts("You sent the following request body to me:\n") 786r:puts(input)</pre> 787 788 789<pre class="prettyprint lang-lua">r:add_input_filter(filter_name) -- Adds 'filter_name' as an input filter</pre> 790 791 792<pre class="prettyprint lang-lua">r.module_info(module_name) -- Queries the server for information about a module 793 794local mod = r.module_info("mod_lua.c") 795if mod then 796 for k, v in pairs(mod.commands) do 797 r:puts( ("%s: %s\n"):format(k,v)) -- print out all directives accepted by this module 798 end 799end</pre> 800 801 802<pre class="prettyprint lang-lua">r:loaded_modules() -- Returns a list of modules loaded by httpd: 803 804for k, module in pairs(r:loaded_modules()) do 805 r:puts("I have loaded module " .. module .. "\n") 806end</pre> 807 808 809<pre class="prettyprint lang-lua">r:runtime_dir_relative(filename) -- Compute the name of a run-time file (e.g., shared memory "file") 810 -- relative to the appropriate run-time directory.</pre> 811 812 813<pre class="prettyprint lang-lua">r:server_info() -- Returns a table containing server information, such as 814 -- the name of the httpd executable file, mpm used etc.</pre> 815 816 817<pre class="prettyprint lang-lua">r:set_document_root(file_path) -- Sets the document root for the request to file_path</pre> 818 819 820 821 822<pre class="prettyprint lang-lua">r:set_context_info(prefix, docroot) -- Sets the context prefix and context document root for a request</pre> 823 824 825<pre class="prettyprint lang-lua">r:os_escape_path(file_path) -- Converts an OS path to a URL in an OS dependent way</pre> 826 827 828<pre class="prettyprint lang-lua">r:escape_logitem(string) -- Escapes a string for logging</pre> 829 830 831<pre class="prettyprint lang-lua">r.strcmp_match(string, pattern) -- Checks if 'string' matches 'pattern' using strcmp_match (globs). 832 -- fx. whether 'www.example.com' matches '*.example.com': 833 834local match = r.strcmp_match("foobar.com", "foo*.com") 835if match then 836 r:puts("foobar.com matches foo*.com") 837end</pre> 838 839 840<pre class="prettyprint lang-lua">r:set_keepalive() -- Sets the keepalive status for a request. Returns true if possible, false otherwise.</pre> 841 842 843<pre class="prettyprint lang-lua">r:make_etag() -- Constructs and returns the etag for the current request.</pre> 844 845 846<pre class="prettyprint lang-lua">r:send_interim_response(clear) -- Sends an interim (1xx) response to the client. 847 -- if 'clear' is true, available headers will be sent and cleared.</pre> 848 849 850<pre class="prettyprint lang-lua">r:custom_response(status_code, string) -- Construct and set a custom response for a given status code. 851 -- This works much like the ErrorDocument directive: 852 853r:custom_response(404, "Baleted!")</pre> 854 855 856<pre class="prettyprint lang-lua">r.exists_config_define(string) -- Checks whether a configuration definition exists or not: 857 858if r.exists_config_define("FOO") then 859 r:puts("httpd was probably run with -DFOO, or it was defined in the configuration") 860end</pre> 861 862 863<pre class="prettyprint lang-lua">r:state_query(string) -- Queries the server for state information</pre> 864 865 866<pre class="prettyprint lang-lua">r:stat(filename [,wanted]) -- Runs stat() on a file, and returns a table with file information: 867 868local info = r:stat("/var/www/foo.txt") 869if info then 870 r:puts("This file exists and was last modified at: " .. info.modified) 871end</pre> 872 873 874<pre class="prettyprint lang-lua">r:regex(string, pattern [,flags]) -- Runs a regular expression match on a string, returning captures if matched: 875 876local matches = r:regex("foo bar baz", [[foo (\w+) (\S*)]]) 877if matches then 878 r:puts("The regex matched, and the last word captured ($2) was: " .. matches[2]) 879end 880 881-- Example ignoring case sensitivity: 882local matches = r:regex("FOO bar BAz", [[(foo) bar]], 1) 883 884-- Flags can be a bitwise combination of: 885-- 0x01: Ignore case 886-- 0x02: Multiline search</pre> 887 888 889<pre class="prettyprint lang-lua">r.usleep(number_of_microseconds) -- Puts the script to sleep for a given number of microseconds.</pre> 890 891 892<pre class="prettyprint lang-lua">r:dbacquire(dbType[, dbParams]) -- Acquires a connection to a database and returns a database class. 893 -- See '<a href="#databases">Database connectivity</a>' for details.</pre> 894 895 896<pre class="prettyprint lang-lua">r:ivm_set("key", value) -- Set an Inter-VM variable to hold a specific value. 897 -- These values persist even though the VM is gone or not being used, 898 -- and so should only be used if MaxConnectionsPerChild is > 0 899 -- Values can be numbers, strings and booleans, and are stored on a 900 -- per process basis (so they won't do much good with a prefork mpm) 901 902r:ivm_get("key") -- Fetches a variable set by ivm_set. Returns the contents of the variable 903 -- if it exists or nil if no such variable exists. 904 905-- An example getter/setter that saves a global variable outside the VM: 906function handle(r) 907 -- First VM to call this will get no value, and will have to create it 908 local foo = r:ivm_get("cached_data") 909 if not foo then 910 foo = do_some_calcs() -- fake some return value 911 r:ivm_set("cached_data", foo) -- set it globally 912 end 913 r:puts("Cached data is: ", foo) 914end</pre> 915 916 917<pre class="prettyprint lang-lua">r:htpassword(string [,algorithm [,cost]]) -- Creates a password hash from a string. 918 -- algorithm: 0 = APMD5 (default), 1 = SHA, 2 = BCRYPT, 3 = CRYPT. 919 -- cost: only valid with BCRYPT algorithm (default = 5).</pre> 920 921 922<pre class="prettyprint lang-lua">r:mkdir(dir [,mode]) -- Creates a directory and sets mode to optional mode paramter.</pre> 923 924 925<pre class="prettyprint lang-lua">r:mkrdir(dir [,mode]) -- Creates directories recursive and sets mode to optional mode paramter.</pre> 926 927 928<pre class="prettyprint lang-lua">r:rmdir(dir) -- Removes a directory.</pre> 929 930 931<pre class="prettyprint lang-lua">r:touch(file [,mtime]) -- Sets the file modification time to current time or to optional mtime msec value.</pre> 932 933 934<pre class="prettyprint lang-lua">r:get_direntries(dir) -- Returns a table with all directory entries. 935 936function handle(r) 937 local dir = r.context_document_root 938 for _, f in ipairs(r:get_direntries(dir)) do 939 local info = r:stat(dir .. "/" .. f) 940 if info then 941 local mtime = os.date(fmt, info.mtime / 1000000) 942 local ftype = (info.filetype == 2) and "[dir] " or "[file]" 943 r:puts( ("%s %s %10i %s\n"):format(ftype, mtime, info.size, f) ) 944 end 945 end 946end</pre> 947 948 949<pre class="prettyprint lang-lua">r.date_parse_rfc(string) -- Parses a date/time string and returns seconds since epoche.</pre> 950 951 952<pre class="prettyprint lang-lua">r:getcookie(key) -- Gets a HTTP cookie</pre> 953 954 955<pre class="prettyprint lang-lua">r:setcookie{ 956 key = [key], 957 value = [value], 958 expires = [expiry], 959 secure = [boolean], 960 httponly = [boolean], 961 path = [path], 962 domain = [domain] 963} -- Sets a HTTP cookie, for instance: 964 965r:setcookie{ 966 key = "cookie1", 967 value = "HDHfa9eyffh396rt", 968 expires = os.time() + 86400, 969 secure = true 970}</pre> 971 972 973<pre class="prettyprint lang-lua">r:wsupgrade() -- Upgrades a connection to WebSockets if possible (and requested): 974if r:wsupgrade() then -- if we can upgrade: 975 r:wswrite("Welcome to websockets!") -- write something to the client 976 r:wsclose() -- goodbye! 977end</pre> 978 979 980<pre class="prettyprint lang-lua">r:wsread() -- Reads a WebSocket frame from a WebSocket upgraded connection (see above): 981 982local line, isFinal = r:wsread() -- isFinal denotes whether this is the final frame. 983 -- If it isn't, then more frames can be read 984r:wswrite("You wrote: " .. line)</pre> 985 986 987<pre class="prettyprint lang-lua">r:wswrite(line) -- Writes a frame to a WebSocket client: 988r:wswrite("Hello, world!")</pre> 989 990 991<pre class="prettyprint lang-lua">r:wsclose() -- Closes a WebSocket request and terminates it for httpd: 992 993if r:wsupgrade() then 994 r:wswrite("Write something: ") 995 local line = r:wsread() or "nothing" 996 r:wswrite("You wrote: " .. line); 997 r:wswrite("Goodbye!") 998 r:wsclose() 999end</pre> 1000 1001 1002</div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1003<div class="section"> 1004<h2><a name="logging" id="logging">Logging Functions</a></h2> 1005 1006<pre class="prettyprint lang-lua"> -- examples of logging messages<br /> 1007 r:trace1("This is a trace log message") -- trace1 through trace8 can be used <br /> 1008 r:debug("This is a debug log message")<br /> 1009 r:info("This is an info log message")<br /> 1010 r:notice("This is a notice log message")<br /> 1011 r:warn("This is a warn log message")<br /> 1012 r:err("This is an err log message")<br /> 1013 r:alert("This is an alert log message")<br /> 1014 r:crit("This is a crit log message")<br /> 1015 r:emerg("This is an emerg log message")<br /> 1016</pre> 1017 1018 1019</div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1020<div class="section"> 1021<h2><a name="apache2" id="apache2">apache2 Package</a></h2> 1022<p>A package named <code>apache2</code> is available with (at least) the following contents.</p> 1023<dl> 1024 <dt>apache2.OK</dt> 1025 <dd>internal constant OK. Handlers should return this if they've 1026 handled the request.</dd> 1027 <dt>apache2.DECLINED</dt> 1028 <dd>internal constant DECLINED. Handlers should return this if 1029 they are not going to handle the request.</dd> 1030 <dt>apache2.DONE</dt> 1031 <dd>internal constant DONE.</dd> 1032 <dt>apache2.version</dt> 1033 <dd>Apache HTTP server version string</dd> 1034 <dt>apache2.HTTP_MOVED_TEMPORARILY</dt> 1035 <dd>HTTP status code</dd> 1036 <dt>apache2.PROXYREQ_NONE, apache2.PROXYREQ_PROXY, apache2.PROXYREQ_REVERSE, apache2.PROXYREQ_RESPONSE</dt> 1037 <dd>internal constants used by <code class="module"><a href="/mod/mod_proxy.html">mod_proxy</a></code></dd> 1038 <dt>apache2.AUTHZ_DENIED, apache2.AUTHZ_GRANTED, apache2.AUTHZ_NEUTRAL, apache2.AUTHZ_GENERAL_ERROR, apache2.AUTHZ_DENIED_NO_USER</dt> 1039 <dd>internal constants used by <code class="module"><a href="/mod/mod_authz_core.html">mod_authz_core</a></code></dd> 1040 1041</dl> 1042<p>(Other HTTP status codes are not yet implemented.)</p> 1043</div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1044<div class="section"> 1045<h2><a name="modifying_buckets" id="modifying_buckets">Modifying contents with Lua filters</a></h2> 1046 1047 <p> 1048 Filter functions implemented via <code class="directive"><a href="#luainputfilter">LuaInputFilter</a></code> 1049 or <code class="directive"><a href="#luaoutputfilter">LuaOutputFilter</a></code> are designed as 1050 three-stage non-blocking functions using coroutines to suspend and resume a 1051 function as buckets are sent down the filter chain. The core structure of 1052 such a function is: 1053 </p> 1054 <pre class="prettyprint lang-lua">function filter(r) 1055 -- Our first yield is to signal that we are ready to receive buckets. 1056 -- Before this yield, we can set up our environment, check for conditions, 1057 -- and, if we deem it necessary, decline filtering a request alltogether: 1058 if something_bad then 1059 return -- This would skip this filter. 1060 end 1061 -- Regardless of whether we have data to prepend, a yield MUST be called here. 1062 -- Note that only output filters can prepend data. Input filters must use the 1063 -- final stage to append data to the content. 1064 coroutine.yield([optional header to be prepended to the content]) 1065 1066 -- After we have yielded, buckets will be sent to us, one by one, and we can 1067 -- do whatever we want with them and then pass on the result. 1068 -- Buckets are stored in the global variable 'bucket', so we create a loop 1069 -- that checks if 'bucket' is not nil: 1070 while bucket ~= nil do 1071 local output = mangle(bucket) -- Do some stuff to the content 1072 coroutine.yield(output) -- Return our new content to the filter chain 1073 end 1074 1075 -- Once the buckets are gone, 'bucket' is set to nil, which will exit the 1076 -- loop and land us here. Anything extra we want to append to the content 1077 -- can be done by doing a final yield here. Both input and output filters 1078 -- can append data to the content in this phase. 1079 coroutine.yield([optional footer to be appended to the content]) 1080end</pre> 1081 1082</div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1083<div class="section"> 1084<h2><a name="databases" id="databases">Database connectivity</a></h2> 1085 1086 <p> 1087 Mod_lua implements a simple database feature for querying and running commands 1088 on the most popular database engines (mySQL, PostgreSQL, FreeTDS, ODBC, SQLite, Oracle) 1089 as well as mod_dbd. 1090 </p> 1091 <p>The example below shows how to acquire a database handle and return information from a table:</p> 1092 <pre class="prettyprint lang-lua">function handle(r) 1093 -- Acquire a database handle 1094 local database, err = r:dbacquire("mysql", "server=localhost,user=someuser,pass=somepass,dbname=mydb") 1095 if not err then 1096 -- Select some information from it 1097 local results, err = database:select(r, "SELECT `name`, `age` FROM `people` WHERE 1") 1098 if not err then 1099 local rows = results(0) -- fetch all rows synchronously 1100 for k, row in pairs(rows) do 1101 r:puts( string.format("Name: %s, Age: %s<br/>", row[1], row[2]) ) 1102 end 1103 else 1104 r:puts("Database query error: " .. err) 1105 end 1106 database:close() 1107 else 1108 r:puts("Could not connect to the database: " .. err) 1109 end 1110end</pre> 1111 1112 <p> 1113 To utilize <code class="module"><a href="/mod/mod_dbd.html">mod_dbd</a></code>, specify <code>mod_dbd</code> 1114 as the database type, or leave the field blank: 1115 </p> 1116 <pre class="prettyprint lang-lua">local database = r:dbacquire("mod_dbd")</pre> 1117 1118 <h3><a name="database_object" id="database_object">Database object and contained functions</a></h3> 1119 1120 <p>The database object returned by <code>dbacquire</code> has the following methods:</p> 1121 <p><strong>Normal select and query from a database:</strong></p> 1122 <pre class="prettyprint lang-lua">-- Run a statement and return the number of rows affected: 1123local affected, errmsg = database:query(r, "DELETE FROM `tbl` WHERE 1") 1124 1125-- Run a statement and return a result set that can be used synchronously or async: 1126local result, errmsg = database:select(r, "SELECT * FROM `people` WHERE 1")</pre> 1127 1128 <p><strong>Using prepared statements (recommended):</strong></p> 1129 <pre class="prettyprint lang-lua">-- Create and run a prepared statement: 1130local statement, errmsg = database:prepare(r, "DELETE FROM `tbl` WHERE `age` > %u") 1131if not errmsg then 1132 local result, errmsg = statement:query(20) -- run the statement with age > 20 1133end 1134 1135-- Fetch a prepared statement from a DBDPrepareSQL directive: 1136local statement, errmsg = database:prepared(r, "someTag") 1137if not errmsg then 1138 local result, errmsg = statement:select("John Doe", 123) -- inject the values "John Doe" and 123 into the statement 1139end</pre> 1140 1141 <p><strong>Escaping values, closing databases etc:</strong></p> 1142 <pre class="prettyprint lang-lua">-- Escape a value for use in a statement: 1143local escaped = database:escape(r, [["'|blabla]]) 1144 1145-- Close a database connection and free up handles: 1146database:close() 1147 1148-- Check whether a database connection is up and running: 1149local connected = database:active()</pre> 1150 1151 1152 <h3><a name="result_sets" id="result_sets">Working with result sets</a></h3> 1153 1154 <p>The result set returned by <code>db:select</code> or by the prepared statement functions 1155 created through <code>db:prepare</code> can be used to 1156 fetch rows synchronously or asynchronously, depending on the row number specified:<br /> 1157 <code>result(0)</code> fetches all rows in a synchronous manner, returning a table of rows.<br /> 1158 <code>result(-1)</code> fetches the next available row in the set, asynchronously.<br /> 1159 <code>result(N)</code> fetches row number <code>N</code>, asynchronously: 1160 </p> 1161 <pre class="prettyprint lang-lua">-- fetch a result set using a regular query: 1162local result, err = db:select(r, "SELECT * FROM `tbl` WHERE 1") 1163 1164local rows = result(0) -- Fetch ALL rows synchronously 1165local row = result(-1) -- Fetch the next available row, asynchronously 1166local row = result(1234) -- Fetch row number 1234, asynchronously 1167local row = result(-1, true) -- Fetch the next available row, using row names as key indexes.</pre> 1168 1169 <p>One can construct a function that returns an iterative function to iterate over all rows 1170 in a synchronous or asynchronous way, depending on the async argument: 1171 </p> 1172 <pre class="prettyprint lang-lua">function rows(resultset, async) 1173 local a = 0 1174 local function getnext() 1175 a = a + 1 1176 local row = resultset(-1) 1177 return row and a or nil, row 1178 end 1179 if not async then 1180 return pairs(resultset(0)) 1181 else 1182 return getnext, self 1183 end 1184end 1185 1186local statement, err = db:prepare(r, "SELECT * FROM `tbl` WHERE `age` > %u") 1187if not err then 1188 -- fetch rows asynchronously: 1189 local result, err = statement:select(20) 1190 if not err then 1191 for index, row in rows(result, true) do 1192 .... 1193 end 1194 end 1195 1196 -- fetch rows synchronously: 1197 local result, err = statement:select(20) 1198 if not err then 1199 for index, row in rows(result, false) do 1200 .... 1201 end 1202 end 1203end</pre> 1204 1205 1206 <h3><a name="closing_databases" id="closing_databases">Closing a database connection</a></h3> 1207 1208 1209 <p>Database handles should be closed using <code>database:close()</code> when they are no longer 1210 needed. If you do not close them manually, they will eventually be garbage collected and 1211 closed by mod_lua, but you may end up having too many unused connections to the database 1212 if you leave the closing up to mod_lua. Essentially, the following two measures are 1213 the same: 1214 </p> 1215 <pre class="prettyprint lang-lua">-- Method 1: Manually close a handle 1216local database = r:dbacquire("mod_dbd") 1217database:close() -- All done 1218 1219-- Method 2: Letting the garbage collector close it 1220local database = r:dbacquire("mod_dbd") 1221database = nil -- throw away the reference 1222collectgarbage() -- close the handle via GC</pre> 1223 1224 1225 <h3><a name="database_caveat" id="database_caveat">Precautions when working with databases</a></h3> 1226 1227 <p>Although the standard <code>query</code> and <code>run</code> functions are freely 1228 available, it is recommended that you use prepared statements whenever possible, to 1229 both optimize performance (if your db handle lives on for a long time) and to minimize 1230 the risk of SQL injection attacks. <code>run</code> and <code>query</code> should only 1231 be used when there are no variables inserted into a statement (a static statement). 1232 When using dynamic statements, use <code>db:prepare</code> or <code>db:prepared</code>. 1233 </p> 1234 1235 1236</div> 1237<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1238<div class="directive-section"><h2><a name="LuaAuthzProvider" id="LuaAuthzProvider">LuaAuthzProvider</a> <a name="luaauthzprovider" id="luaauthzprovider">Directive</a></h2> 1239<table class="directive"> 1240<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> 1241</td></tr> 1242<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> 1243<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> 1244<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1245<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1246<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.4.3 and later</td></tr> 1247</table> 1248<p>After a lua function has been registered as authorization provider, it can be used 1249with the <code class="directive"><a href="/mod/mod_authz_core.html#require">Require</a></code> directive:</p> 1250 1251<pre class="prettyprint lang-config">LuaRoot /usr/local/apache2/lua 1252LuaAuthzProvider foo authz.lua authz_check_foo 1253<Location /> 1254 Require foo johndoe 1255</Location></pre> 1256 1257<pre class="prettyprint lang-lua">require "apache2" 1258function authz_check_foo(r, who) 1259 if r.user ~= who then return apache2.AUTHZ_DENIED 1260 return apache2.AUTHZ_GRANTED 1261end</pre> 1262 1263 1264 1265 1266</div> 1267<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1268<div class="directive-section"><h2><a name="LuaCodeCache" id="LuaCodeCache">LuaCodeCache</a> <a name="luacodecache" id="luacodecache">Directive</a></h2> 1269<table class="directive"> 1270<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configure the compiled code cache.</td></tr> 1271<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaCodeCache stat|forever|never</code></td></tr> 1272<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LuaCodeCache stat</code></td></tr> 1273<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1274<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1275<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1276<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1277</table><p> 1278 Specify the behavior of the in-memory code cache. The default 1279 is stat, which stats the top level script (not any included 1280 ones) each time that file is needed, and reloads it if the 1281 modified time indicates it is newer than the one it has 1282 already loaded. The other values cause it to keep the file 1283 cached forever (don't stat and replace) or to never cache the 1284 file.</p> 1285 1286 <p>In general stat or forever is good for production, and stat or never 1287 for development.</p> 1288 1289 <div class="example"><h3>Examples:</h3><pre class="prettyprint lang-config">LuaCodeCache stat 1290LuaCodeCache forever 1291LuaCodeCache never</pre> 1292</div> 1293 1294 1295</div> 1296<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1297<div class="directive-section"><h2><a name="LuaHookAccessChecker" id="LuaHookAccessChecker">LuaHookAccessChecker</a> <a name="luahookaccesschecker" id="luahookaccesschecker">Directive</a></h2> 1298<table class="directive"> 1299<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> 1300<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> 1301<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1302<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1303<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1304<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1305<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> 1306</table> 1307<p>Add your hook to the access_checker phase. An access checker 1308hook function usually returns OK, DECLINED, or HTTP_FORBIDDEN.</p> 1309 <div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late" 1310 control when this script runs relative to other modules.</p></div> 1311 1312</div> 1313<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1314<div class="directive-section"><h2><a name="LuaHookAuthChecker" id="LuaHookAuthChecker">LuaHookAuthChecker</a> <a name="luahookauthchecker" id="luahookauthchecker">Directive</a></h2> 1315<table class="directive"> 1316<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> 1317<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> 1318<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1319<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1320<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1321<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1322<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> 1323</table> 1324<p>Invoke a lua function in the auth_checker phase of processing 1325a request. This can be used to implement arbitrary authentication 1326and authorization checking. A very simple example: 1327</p> 1328<pre class="prettyprint lang-lua">require 'apache2' 1329 1330-- fake authcheck hook 1331-- If request has no auth info, set the response header and 1332-- return a 401 to ask the browser for basic auth info. 1333-- If request has auth info, don't actually look at it, just 1334-- pretend we got userid 'foo' and validated it. 1335-- Then check if the userid is 'foo' and accept the request. 1336function authcheck_hook(r) 1337 1338 -- look for auth info 1339 auth = r.headers_in['Authorization'] 1340 if auth ~= nil then 1341 -- fake the user 1342 r.user = 'foo' 1343 end 1344 1345 if r.user == nil then 1346 r:debug("authcheck: user is nil, returning 401") 1347 r.err_headers_out['WWW-Authenticate'] = 'Basic realm="WallyWorld"' 1348 return 401 1349 elseif r.user == "foo" then 1350 r:debug('user foo: OK') 1351 else 1352 r:debug("authcheck: user='" .. r.user .. "'") 1353 r.err_headers_out['WWW-Authenticate'] = 'Basic realm="WallyWorld"' 1354 return 401 1355 end 1356 return apache2.OK 1357end</pre> 1358 1359 <div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late" 1360 control when this script runs relative to other modules.</p></div> 1361 1362</div> 1363<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1364<div class="directive-section"><h2><a name="LuaHookCheckUserID" id="LuaHookCheckUserID">LuaHookCheckUserID</a> <a name="luahookcheckuserid" id="luahookcheckuserid">Directive</a></h2> 1365<table class="directive"> 1366<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> 1367<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> 1368<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1369<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1370<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1371<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1372<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> 1373</table><p>...</p> 1374 <div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late" 1375 control when this script runs relative to other modules.</p></div> 1376 1377</div> 1378<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1379<div class="directive-section"><h2><a name="LuaHookFixups" id="LuaHookFixups">LuaHookFixups</a> <a name="luahookfixups" id="luahookfixups">Directive</a></h2> 1380<table class="directive"> 1381<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the fixups phase of a request 1382processing</td></tr> 1383<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> 1384<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1385<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1386<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1387<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1388</table> 1389<p> 1390 Just like LuaHookTranslateName, but executed at the fixups phase 1391</p> 1392 1393</div> 1394<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1395<div class="directive-section"><h2><a name="LuaHookInsertFilter" id="LuaHookInsertFilter">LuaHookInsertFilter</a> <a name="luahookinsertfilter" id="luahookinsertfilter">Directive</a></h2> 1396<table class="directive"> 1397<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> 1398<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> 1399<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1400<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1401<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1402<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1403</table><p>Not Yet Implemented</p> 1404</div> 1405<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1406<div class="directive-section"><h2><a name="LuaHookLog" id="LuaHookLog">LuaHookLog</a> <a name="luahooklog" id="luahooklog">Directive</a></h2> 1407<table class="directive"> 1408<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the access log phase of a request 1409processing</td></tr> 1410<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookLog /path/to/lua/script.lua log_function_name</code></td></tr> 1411<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1412<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1413<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1414<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1415</table> 1416<p> 1417 This simple logging hook allows you to run a function when httpd enters the 1418 logging phase of a request. With it, you can append data to your own logs, 1419 manipulate data before the regular log is written, or prevent a log entry 1420 from being created. To prevent the usual logging from happening, simply return 1421 <code>apache2.DONE</code> in your logging handler, otherwise return 1422 <code>apache2.OK</code> to tell httpd to log as normal. 1423</p> 1424<p>Example:</p> 1425<pre class="prettyprint lang-config">LuaHookLog /path/to/script.lua logger</pre> 1426 1427<pre class="prettyprint lang-lua">-- /path/to/script.lua -- 1428function logger(r) 1429 -- flip a coin: 1430 -- If 1, then we write to our own Lua log and tell httpd not to log 1431 -- in the main log. 1432 -- If 2, then we just sanitize the output a bit and tell httpd to 1433 -- log the sanitized bits. 1434 1435 if math.random(1,2) == 1 then 1436 -- Log stuff ourselves and don't log in the regular log 1437 local f = io.open("/foo/secret.log", "a") 1438 if f then 1439 f:write("Something secret happened at " .. r.uri .. "\n") 1440 f:close() 1441 end 1442 return apache2.DONE -- Tell httpd not to use the regular logging functions 1443 else 1444 r.uri = r.uri:gsub("somesecretstuff", "") -- sanitize the URI 1445 return apache2.OK -- tell httpd to log it. 1446 end 1447end</pre> 1448 1449 1450</div> 1451<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1452<div class="directive-section"><h2><a name="LuaHookMapToStorage" id="LuaHookMapToStorage">LuaHookMapToStorage</a> <a name="luahookmaptostorage" id="luahookmaptostorage">Directive</a></h2> 1453<table class="directive"> 1454<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> 1455<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> 1456<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1457<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1458<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1459<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1460</table> 1461 <p>Like <code class="directive">LuaHookTranslateName</code> but executed at the 1462 map-to-storage phase of a request. Modules like mod_cache run at this phase, 1463 which makes for an interesting example on what to do here:</p> 1464 <pre class="prettyprint lang-config">LuaHookMapToStorage /path/to/lua/script.lua check_cache</pre> 1465 1466 <pre class="prettyprint lang-lua">require"apache2" 1467cached_files = {} 1468 1469function read_file(filename) 1470 local input = io.open(filename, "r") 1471 if input then 1472 local data = input:read("*a") 1473 cached_files[filename] = data 1474 file = cached_files[filename] 1475 input:close() 1476 end 1477 return cached_files[filename] 1478end 1479 1480function check_cache(r) 1481 if r.filename:match("%.png$") then -- Only match PNG files 1482 local file = cached_files[r.filename] -- Check cache entries 1483 if not file then 1484 file = read_file(r.filename) -- Read file into cache 1485 end 1486 if file then -- If file exists, write it out 1487 r.status = 200 1488 r:write(file) 1489 r:info(("Sent %s to client from cache"):format(r.filename)) 1490 return apache2.DONE -- skip default handler for PNG files 1491 end 1492 end 1493 return apache2.DECLINED -- If we had nothing to do, let others serve this. 1494end</pre> 1495 1496 1497 1498</div> 1499<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1500<div class="directive-section"><h2><a name="LuaHookTranslateName" id="LuaHookTranslateName">LuaHookTranslateName</a> <a name="luahooktranslatename" id="luahooktranslatename">Directive</a></h2> 1501<table class="directive"> 1502<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> 1503<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> 1504<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> 1505<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1506<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1507<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1508<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> 1509</table><p> 1510 Add a hook (at APR_HOOK_MIDDLE) to the translate name phase of 1511 request processing. The hook function receives a single 1512 argument, the request_rec, and should return a status code, 1513 which is either an HTTP error code, or the constants defined 1514 in the apache2 module: apache2.OK, apache2.DECLINED, or 1515 apache2.DONE. </p> 1516 1517 <p>For those new to hooks, basically each hook will be invoked 1518 until one of them returns apache2.OK. If your hook doesn't 1519 want to do the translation it should just return 1520 apache2.DECLINED. If the request should stop processing, then 1521 return apache2.DONE.</p> 1522 1523 <p>Example:</p> 1524 1525<pre class="prettyprint lang-config"># httpd.conf 1526LuaHookTranslateName /scripts/conf/hooks.lua silly_mapper</pre> 1527 1528 1529<pre class="prettyprint lang-lua">-- /scripts/conf/hooks.lua -- 1530require "apache2" 1531function silly_mapper(r) 1532 if r.uri == "/" then 1533 r.filename = "/var/www/home.lua" 1534 return apache2.OK 1535 else 1536 return apache2.DECLINED 1537 end 1538end</pre> 1539 1540 1541 <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 1542 context.</p></div> 1543 1544 <div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late" 1545 control when this script runs relative to other modules.</p></div> 1546 1547 1548</div> 1549<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1550<div class="directive-section"><h2><a name="LuaHookTypeChecker" id="LuaHookTypeChecker">LuaHookTypeChecker</a> <a name="luahooktypechecker" id="luahooktypechecker">Directive</a></h2> 1551<table class="directive"> 1552<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> 1553<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> 1554<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1555<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1556<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1557<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1558</table><p> 1559 This directive provides a hook for the type_checker phase of the request processing. 1560 This phase is where requests are assigned a content type and a handler, and thus can 1561 be used to modify the type and handler based on input: 1562 </p> 1563 <pre class="prettyprint lang-config">LuaHookTypeChecker /path/to/lua/script.lua type_checker</pre> 1564 1565 <pre class="prettyprint lang-lua"> function type_checker(r) 1566 if r.uri:match("%.to_gif$") then -- match foo.png.to_gif 1567 r.content_type = "image/gif" -- assign it the image/gif type 1568 r.handler = "gifWizard" -- tell the gifWizard module to handle this 1569 r.filename = r.uri:gsub("%.to_gif$", "") -- fix the filename requested 1570 return apache2.OK 1571 end 1572 1573 return apache2.DECLINED 1574 end</pre> 1575 1576 1577</div> 1578<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1579<div class="directive-section"><h2><a name="LuaInherit" id="LuaInherit">LuaInherit</a> <a name="luainherit" id="luainherit">Directive</a></h2> 1580<table class="directive"> 1581<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Controls how parent configuration sections are merged into children</td></tr> 1582<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaInherit none|parent-first|parent-last</code></td></tr> 1583<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LuaInherit parent-first</code></td></tr> 1584<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1585<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1586<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1587<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1588<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.4.0 and later</td></tr> 1589</table><p>By default, if LuaHook* directives are used in overlapping 1590 Directory or Location configuration sections, the scripts defined in the 1591 more specific section are run <em>after</em> those defined in the more 1592 generic section (LuaInherit parent-first). You can reverse this order, or 1593 make the parent context not apply at all.</p> 1594 1595 <p> In previous 2.3.x releases, the default was effectively to ignore LuaHook* 1596 directives from parent configuration sections.</p> 1597</div> 1598<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1599<div class="directive-section"><h2><a name="LuaInputFilter" id="LuaInputFilter">LuaInputFilter</a> <a name="luainputfilter" id="luainputfilter">Directive</a></h2> 1600<table class="directive"> 1601<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a Lua function for content input filtering</td></tr> 1602<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaInputFilter filter_name /path/to/lua/script.lua function_name</code></td></tr> 1603<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> 1604<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1605<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1606<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.5.0 and later</td></tr> 1607</table> 1608<p>Provides a means of adding a Lua function as an input filter. 1609As with output filters, input filters work as coroutines, 1610first yielding before buffers are sent, then yielding whenever 1611a bucket needs to be passed down the chain, and finally (optionally) 1612yielding anything that needs to be appended to the input data. The 1613global variable <code>bucket</code> holds the buckets as they are passed 1614onto the Lua script: 1615</p> 1616 1617<pre class="prettyprint lang-config">LuaInputFilter myInputFilter /www/filter.lua input_filter 1618<Files *.lua> 1619 SetInputFilter myInputFilter 1620</Files></pre> 1621 1622<pre class="prettyprint lang-lua">--[[ 1623 Example input filter that converts all POST data to uppercase. 1624]]-- 1625function input_filter(r) 1626 print("luaInputFilter called") -- debug print 1627 coroutine.yield() -- Yield and wait for buckets 1628 while bucket do -- For each bucket, do... 1629 local output = string.upper(bucket) -- Convert all POST data to uppercase 1630 coroutine.yield(output) -- Send converted data down the chain 1631 end 1632 -- No more buckets available. 1633 coroutine.yield("&filterSignature=1234") -- Append signature at the end 1634end</pre> 1635 1636<p> 1637The input filter supports denying/skipping a filter if it is deemed unwanted: 1638</p> 1639<pre class="prettyprint lang-lua">function input_filter(r) 1640 if not good then 1641 return -- Simply deny filtering, passing on the original content instead 1642 end 1643 coroutine.yield() -- wait for buckets 1644 ... -- insert filter stuff here 1645end</pre> 1646 1647<p> 1648See "<a href="#modifying_buckets">Modifying contents with Lua 1649filters</a>" for more information. 1650</p> 1651 1652</div> 1653<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1654<div class="directive-section"><h2><a name="LuaMapHandler" id="LuaMapHandler">LuaMapHandler</a> <a name="luamaphandler" id="luamaphandler">Directive</a></h2> 1655<table class="directive"> 1656<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Map a path to a lua handler</td></tr> 1657<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> 1658<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1659<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1660<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1661<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1662</table> 1663 <p>This directive matches a uri pattern to invoke a specific 1664 handler function in a specific file. It uses PCRE regular 1665 expressions to match the uri, and supports interpolating 1666 match groups into both the file path and the function name. 1667 Be careful writing your regular expressions to avoid security 1668 issues.</p> 1669 <div class="example"><h3>Examples:</h3><pre class="prettyprint lang-config">LuaMapHandler /(\w+)/(\w+) /scripts/$1.lua handle_$2</pre> 1670</div> 1671 <p>This would match uri's such as /photos/show?id=9 1672 to the file /scripts/photos.lua and invoke the 1673 handler function handle_show on the lua vm after 1674 loading that file.</p> 1675 1676<pre class="prettyprint lang-config">LuaMapHandler /bingo /scripts/wombat.lua</pre> 1677 1678 <p>This would invoke the "handle" function, which 1679 is the default if no specific function name is 1680 provided.</p> 1681 1682</div> 1683<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1684<div class="directive-section"><h2><a name="LuaOutputFilter" id="LuaOutputFilter">LuaOutputFilter</a> <a name="luaoutputfilter" id="luaoutputfilter">Directive</a></h2> 1685<table class="directive"> 1686<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a Lua function for content output filtering</td></tr> 1687<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaOutputFilter filter_name /path/to/lua/script.lua function_name</code></td></tr> 1688<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> 1689<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1690<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1691<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.5.0 and later</td></tr> 1692</table> 1693<p>Provides a means of adding a Lua function as an output filter. 1694As with input filters, output filters work as coroutines, 1695first yielding before buffers are sent, then yielding whenever 1696a bucket needs to be passed down the chain, and finally (optionally) 1697yielding anything that needs to be appended to the input data. The 1698global variable <code>bucket</code> holds the buckets as they are passed 1699onto the Lua script: 1700</p> 1701 1702<pre class="prettyprint lang-config">LuaOutputFilter myOutputFilter /www/filter.lua output_filter 1703<Files *.lua> 1704 SetOutputFilter myOutputFilter 1705</Files></pre> 1706 1707<pre class="prettyprint lang-lua">--[[ 1708 Example output filter that escapes all HTML entities in the output 1709]]-- 1710function output_filter(r) 1711 coroutine.yield("(Handled by myOutputFilter)<br/>\n") -- Prepend some data to the output, 1712 -- yield and wait for buckets. 1713 while bucket do -- For each bucket, do... 1714 local output = r:escape_html(bucket) -- Escape all output 1715 coroutine.yield(output) -- Send converted data down the chain 1716 end 1717 -- No more buckets available. 1718end</pre> 1719 1720<p> 1721As with the input filter, the output filter supports denying/skipping a filter 1722if it is deemed unwanted: 1723</p> 1724<pre class="prettyprint lang-lua">function output_filter(r) 1725 if not r.content_type:match("text/html") then 1726 return -- Simply deny filtering, passing on the original content instead 1727 end 1728 coroutine.yield() -- wait for buckets 1729 ... -- insert filter stuff here 1730end</pre> 1731 1732<div class="note"><h3>Lua filters with <code class="module"><a href="/mod/mod_filter.html">mod_filter</a></code></h3> 1733<p> When a Lua filter is used as the underlying provider via the 1734<code class="directive"><a href="/mod/mod_filter.html#filterprovider">FilterProvider</a></code> directive, filtering 1735will only work when the <var>filter-name</var> is identical to the <var>provider-name</var>. 1736</p> </div> 1737 1738<p> 1739See "<a href="#modifying_buckets">Modifying contents with Lua filters</a>" for more 1740information. 1741</p> 1742 1743 1744</div> 1745<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1746<div class="directive-section"><h2><a name="LuaPackageCPath" id="LuaPackageCPath">LuaPackageCPath</a> <a name="luapackagecpath" id="luapackagecpath">Directive</a></h2> 1747<table class="directive"> 1748<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Add a directory to lua's package.cpath</td></tr> 1749<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaPackageCPath /path/to/include/?.soa</code></td></tr> 1750<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1751<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1752<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1753<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1754</table> 1755 <p>Add a path to lua's shared library search path. Follows the same 1756 conventions as lua. This just munges the package.cpath in the 1757 lua vms.</p> 1758 1759 1760</div> 1761<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1762<div class="directive-section"><h2><a name="LuaPackagePath" id="LuaPackagePath">LuaPackagePath</a> <a name="luapackagepath" id="luapackagepath">Directive</a></h2> 1763<table class="directive"> 1764<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Add a directory to lua's package.path</td></tr> 1765<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaPackagePath /path/to/include/?.lua</code></td></tr> 1766<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1767<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1768<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1769<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1770</table><p>Add a path to lua's module search path. Follows the same 1771 conventions as lua. This just munges the package.path in the 1772 lua vms.</p> 1773 1774 <div class="example"><h3>Examples:</h3><pre class="prettyprint lang-config">LuaPackagePath /scripts/lib/?.lua 1775LuaPackagePath /scripts/lib/?/init.lua</pre> 1776</div> 1777 1778</div> 1779<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1780<div class="directive-section"><h2><a name="LuaQuickHandler" id="LuaQuickHandler">LuaQuickHandler</a> <a name="luaquickhandler" id="luaquickhandler">Directive</a></h2> 1781<table class="directive"> 1782<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the quick handler of request processing</td></tr> 1783<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaQuickHandler /path/to/script.lua hook_function_name</code></td></tr> 1784<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> 1785<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1786<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1787<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1788</table> 1789 <p> 1790 This phase is run immediately after the request has been mapped to a virtal host, 1791 and can be used to either do some request processing before the other phases kick 1792 in, or to serve a request without the need to translate, map to storage et cetera. 1793 As this phase is run before anything else, directives such as <code class="directive"><a href="/mod/core.html#location"><Location></a></code> or <code class="directive"><a href="/mod/core.html#directory"><Directory></a></code> are void in this phase, just as 1794 URIs have not been properly parsed yet. 1795 </p> 1796 <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 1797 context.</p></div> 1798 1799</div> 1800<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1801<div class="directive-section"><h2><a name="LuaRoot" id="LuaRoot">LuaRoot</a> <a name="luaroot" id="luaroot">Directive</a></h2> 1802<table class="directive"> 1803<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> 1804<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaRoot /path/to/a/directory</code></td></tr> 1805<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1806<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1807<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1808<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1809</table> 1810 <p>Specify the base path which will be used to evaluate all 1811 relative paths within mod_lua. If not specified they 1812 will be resolved relative to the current working directory, 1813 which may not always work well for a server.</p> 1814 1815</div> 1816<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div> 1817<div class="directive-section"><h2><a name="LuaScope" id="LuaScope">LuaScope</a> <a name="luascope" id="luascope">Directive</a></h2> 1818<table class="directive"> 1819<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>One of once, request, conn, thread -- default is once</td></tr> 1820<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaScope once|request|conn|thread|server [min] [max]</code></td></tr> 1821<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LuaScope once</code></td></tr> 1822<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> 1823<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr> 1824<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> 1825<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr> 1826</table> 1827 <p>Specify the life cycle scope of the Lua interpreter which will 1828 be used by handlers in this "Directory." The default is "once"</p> 1829 1830 <dl> 1831 <dt>once:</dt> <dd>use the interpreter once and throw it away.</dd> 1832 1833 <dt>request:</dt> <dd>use the interpreter to handle anything based on 1834 the same file within this request, which is also 1835 request scoped.</dd> 1836 1837 <dt>conn:</dt> <dd>Same as request but attached to the connection_rec</dd> 1838 1839 <dt>thread:</dt> <dd>Use the interpreter for the lifetime of the thread 1840 handling the request (only available with threaded MPMs).</dd> 1841 1842 <dt>server:</dt> <dd>This one is different than others because the 1843 server scope is quite long lived, and multiple threads 1844 will have the same server_rec. To accommodate this, 1845 server scoped Lua states are stored in an apr 1846 resource list. The <code>min</code> and <code>max</code> arguments 1847 specify the minimum and maximum number of Lua states to keep in the 1848 pool.</dd> 1849 </dl> 1850 <p> 1851 Generally speaking, the <code>thread</code> and <code>server</code> scopes 1852 execute roughly 2-3 times faster than the rest, because they don't have to 1853 spawn new Lua states on every request (especially with the event MPM, as 1854 even keepalive requests will use a new thread for each request). If you are 1855 satisfied that your scripts will not have problems reusing a state, then 1856 the <code>thread</code> or <code>server</code> scopes should be used for 1857 maximum performance. While the <code>thread</code> scope will provide the 1858 fastest responses, the <code>server</code> scope will use less memory, as 1859 states are pooled, allowing f.x. 1000 threads to share only 100 Lua states, 1860 thus using only 10% of the memory required by the <code>thread</code> scope. 1861 </p> 1862 1863</div> 1864</div> 1865<div class="bottomlang"> 1866<p><span>Available Languages: </span><a href="/en/mod/mod_lua.html" title="English"> en </a> | 1867<a href="/fr/mod/mod_lua.html" hreflang="fr" rel="alternate" title="Fran�ais"> fr </a></p> 1868</div><div class="top"><a href="#page-header"><img src="/images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed again by our moderators if they are either implemented or considered invalid/off-topic. 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