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diff --git a/docs/manual/mod/mod_session.html.en b/docs/manual/mod/mod_session.html.en new file mode 100644 index 0000000..ef3db75 --- /dev/null +++ b/docs/manual/mod/mod_session.html.en @@ -0,0 +1,550 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head> +<meta content="text/html; charset=UTF-8" http-equiv="Content-Type" /> +<!-- + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + This file is generated from xml source: DO NOT EDIT + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + --> +<title>mod_session - Apache HTTP Server Version 2.4</title> +<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> +<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> +<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" /> +<script src="../style/scripts/prettify.min.js" type="text/javascript"> +</script> + +<link href="../images/favicon.ico" rel="shortcut icon" /></head> +<body> +<div id="page-header"> +<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 2.4</p> +<img alt="" src="../images/feather.png" /></div> +<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div> +<div id="path"> +<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> +<div id="page-content"> +<div id="preamble"><h1>Apache Module mod_session</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="../en/mod/mod_session.html" title="English"> en </a> | +<a href="../fr/mod/mod_session.html" hreflang="fr" rel="alternate" title="Français"> fr </a></p> +</div> +<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Session support</td></tr> +<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>session_module</td></tr> +<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_session.c</td></tr> +<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.3 and later</td></tr></table> +<h3>Summary</h3> + + <div class="warning"><h3>Warning</h3> + <p>The session modules make use of HTTP cookies, and as such can fall + victim to Cross Site Scripting attacks, or expose potentially private + information to clients. Please ensure that the relevant risks have + been taken into account before enabling the session functionality on + your server.</p> + </div> + + <p>This module provides support for a server wide per user session + interface. Sessions can be used for keeping track of whether a user + has been logged in, or for other per user information that should + be kept available across requests.</p> + + <p>Sessions may be stored on the server, or may be stored on the + browser. Sessions may also be optionally encrypted for added security. + These features are divided into several modules in addition to + <code class="module"><a href="../mod/mod_session.html">mod_session</a></code>; <code class="module"><a href="../mod/mod_session_crypto.html">mod_session_crypto</a></code>, + <code class="module"><a href="../mod/mod_session_cookie.html">mod_session_cookie</a></code> and <code class="module"><a href="../mod/mod_session_dbd.html">mod_session_dbd</a></code>. + Depending on the server requirements, load the appropriate modules + into the server (either statically at compile time or dynamically + via the <code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code> directive).</p> + + <p>Sessions may be manipulated from other modules that depend on the + session, or the session may be read from and written to using + environment variables and HTTP headers, as appropriate.</p> + +</div> +<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><h3>Topics</h3> +<ul id="topics"> +<li><img alt="" src="../images/down.gif" /> <a href="#whatisasession">What is a session?</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#whocanuseasession">Who can use a session?</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#serversession">Keeping sessions on the server</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#browsersession">Keeping sessions on the browser</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#basicexamples">Basic Examples</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#sessionprivacy">Session Privacy</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#cookieprivacy">Cookie Privacy</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#authentication">Session Support for Authentication</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#integration">Integrating Sessions with External Applications</a></li> +</ul><h3 class="directives">Directives</h3> +<ul id="toc"> +<li><img alt="" src="../images/down.gif" /> <a href="#session">Session</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#sessionenv">SessionEnv</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#sessionexclude">SessionExclude</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#sessionexpiryupdateinterval">SessionExpiryUpdateInterval</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#sessionheader">SessionHeader</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#sessioninclude">SessionInclude</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#sessionmaxage">SessionMaxAge</a></li> +</ul> +<h3>Bugfix checklist</h3><ul class="seealso"><li><a href="https://www.apache.org/dist/httpd/CHANGES_2.4">httpd changelog</a></li><li><a href="https://bz.apache.org/bugzilla/buglist.cgi?bug_status=__open__&list_id=144532&product=Apache%20httpd-2&query_format=specific&order=changeddate%20DESC%2Cpriority%2Cbug_severity&component=mod_session">Known issues</a></li><li><a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2&component=mod_session">Report a bug</a></li></ul><h3>See also</h3> +<ul class="seealso"> +<li><code class="module"><a href="../mod/mod_session_cookie.html">mod_session_cookie</a></code></li> +<li><code class="module"><a href="../mod/mod_session_crypto.html">mod_session_crypto</a></code></li> +<li><code class="module"><a href="../mod/mod_session_dbd.html">mod_session_dbd</a></code></li> +<li><a href="#comments_section">Comments</a></li></ul></div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="whatisasession" id="whatisasession">What is a session?</a></h2> + <p>At the core of the session interface is a table of key and value pairs + that are made accessible across browser requests. These pairs can be set + to any valid string, as needed by the application making use of the + session.</p> + + <p>The "session" is a <strong>application/x-www-form-urlencoded</strong> + string containing these key value pairs, as defined by the + <a href="http://www.w3.org/TR/html4/">HTML specification</a>.</p> + + <p>The session can optionally be encrypted and base64 encoded before + being written to the storage mechanism, as defined by the + administrator.</p> + + </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="whocanuseasession" id="whocanuseasession">Who can use a session?</a></h2> + <p>The session interface is primarily developed for the use by other + server modules, such as <code class="module"><a href="../mod/mod_auth_form.html">mod_auth_form</a></code>, however CGI + based applications can optionally be granted access to the contents + of the session via the HTTP_SESSION environment variable. Sessions + have the option to be modified and/or updated by inserting an HTTP + response header containing the new session parameters.</p> + + </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="serversession" id="serversession">Keeping sessions on the server</a></h2> + <p>Apache can be configured to keep track of per user sessions stored + on a particular server or group of servers. This functionality is + similar to the sessions available in typical application servers.</p> + + <p>If configured, sessions are tracked through the use of a session ID that + is stored inside a cookie, or extracted from the parameters embedded + within the URL query string, as found in a typical GET request.</p> + + <p>As the contents of the session are stored exclusively on the server, + there is an expectation of privacy of the contents of the session. This + does have performance and resource implications should a large number + of sessions be present, or where a large number of webservers have to + share sessions with one another.</p> + + <p>The <code class="module"><a href="../mod/mod_session_dbd.html">mod_session_dbd</a></code> module allows the storage of user + sessions within a SQL database via <code class="module"><a href="../mod/mod_dbd.html">mod_dbd</a></code>.</p> + + </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="browsersession" id="browsersession">Keeping sessions on the browser</a></h2> + <p>In high traffic environments where keeping track of a session on a + server is too resource intensive or inconvenient, the option exists to store + the contents of the session within a cookie on the client browser instead.</p> + + <p>This has the advantage that minimal resources are required on the + server to keep track of sessions, and multiple servers within a server + farm have no need to share session information.</p> + + <p>The contents of the session however are exposed to the client, with a + corresponding risk of a loss of privacy. The + <code class="module"><a href="../mod/mod_session_crypto.html">mod_session_crypto</a></code> module can be configured to encrypt the + contents of the session before writing the session to the client.</p> + + <p>The <code class="module"><a href="../mod/mod_session_cookie.html">mod_session_cookie</a></code> allows the storage of user + sessions on the browser within an HTTP cookie.</p> + + </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="basicexamples" id="basicexamples">Basic Examples</a></h2> + + <p>Creating a session is as simple as turning the session on, and deciding + where the session will be stored. In this example, the session will be + stored on the browser, in a cookie called <code>session</code>.</p> + + <div class="example"><h3>Browser based session</h3><pre class="prettyprint lang-config">Session On +SessionCookieName session path=/</pre> +</div> + + <p>The session is not useful unless it can be written to or read from. The + following example shows how values can be injected into the session through + the use of a predetermined HTTP response header called + <code>X-Replace-Session</code>.</p> + + <div class="example"><h3>Writing to a session</h3><pre class="prettyprint lang-config">Session On +SessionCookieName session path=/ +SessionHeader X-Replace-Session</pre> +</div> + + <p>The header should contain name value pairs expressed in the same format + as a query string in a URL, as in the example below. Setting a key to the + empty string has the effect of removing that key from the session.</p> + + <div class="example"><h3>CGI to write to a session</h3><pre class="prettyprint lang-sh">#!/bin/bash +echo "Content-Type: text/plain" +echo "X-Replace-Session: key1=foo&key2=&key3=bar" +echo +env</pre> +</div> + + <p>If configured, the session can be read back from the HTTP_SESSION + environment variable. By default, the session is kept private, so this + has to be explicitly turned on with the + <code class="directive"><a href="#sessionenv">SessionEnv</a></code> directive.</p> + + <div class="example"><h3>Read from a session</h3><pre class="prettyprint lang-config">Session On +SessionEnv On +SessionCookieName session path=/ +SessionHeader X-Replace-Session</pre> +</div> + + <p>Once read, the CGI variable <code>HTTP_SESSION</code> should contain + the value <code>key1=foo&key3=bar</code>.</p> + + </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="sessionprivacy" id="sessionprivacy">Session Privacy</a></h2> + + <p>Using the "show cookies" feature of your browser, you would have seen + a clear text representation of the session. This could potentially be a + problem should the end user need to be kept unaware of the contents of + the session, or where a third party could gain unauthorised access to the + data within the session.</p> + + <p>The contents of the session can be optionally encrypted before being + placed on the browser using the <code class="module"><a href="../mod/mod_session_crypto.html">mod_session_crypto</a></code> + module.</p> + + <div class="example"><h3>Browser based encrypted session</h3><pre class="prettyprint lang-config">Session On +SessionCryptoPassphrase secret +SessionCookieName session path=/</pre> +</div> + + <p>The session will be automatically decrypted on load, and encrypted on + save by Apache, the underlying application using the session need have + no knowledge that encryption is taking place.</p> + + <p>Sessions stored on the server rather than on the browser can also be + encrypted as needed, offering privacy where potentially sensitive + information is being shared between webservers in a server farm using + the <code class="module"><a href="../mod/mod_session_dbd.html">mod_session_dbd</a></code> module.</p> + + </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="cookieprivacy" id="cookieprivacy">Cookie Privacy</a></h2> + + <p>The HTTP cookie mechanism also offers privacy features, such as the + ability to restrict cookie transport to SSL protected pages only, or + to prevent browser based javascript from gaining access to the contents + of the cookie.</p> + + <div class="warning"><h3>Warning</h3> + <p>Some of the HTTP cookie privacy features are either non-standard, or + are not implemented consistently across browsers. The session modules + allow you to set cookie parameters, but it makes no guarantee that privacy + will be respected by the browser. If security is a concern, use the + <code class="module"><a href="../mod/mod_session_crypto.html">mod_session_crypto</a></code> to encrypt the contents of the session, + or store the session on the server using the <code class="module"><a href="../mod/mod_session_dbd.html">mod_session_dbd</a></code> + module.</p> + </div> + + <p>Standard cookie parameters can be specified after the name of the cookie, + as in the example below.</p> + + <div class="example"><h3>Setting cookie parameters</h3><pre class="prettyprint lang-config">Session On +SessionCryptoPassphrase secret +SessionCookieName session path=/private;domain=example.com;httponly;secure;</pre> +</div> + + <p>In cases where the Apache server forms the frontend for backend origin servers, + it is possible to have the session cookies removed from the incoming HTTP headers using + the <code class="directive"><a href="../mod/mod_session_cookie.html#sessioncookieremove">SessionCookieRemove</a></code> directive. + This keeps the contents of the session cookies from becoming accessible from the + backend server. + </p> + + </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="authentication" id="authentication">Session Support for Authentication</a></h2> + + <p>As is possible within many application servers, authentication modules can use + a session for storing the username and password after login. The + <code class="module"><a href="../mod/mod_auth_form.html">mod_auth_form</a></code> saves the user's login name and password within + the session.</p> + + <div class="example"><h3>Form based authentication</h3><pre class="prettyprint lang-config">Session On +SessionCryptoPassphrase secret +SessionCookieName session path=/ +AuthFormProvider file +AuthUserFile "conf/passwd" +AuthType form +AuthName "realm" +#...</pre> +</div> + + <p>See the <code class="module"><a href="../mod/mod_auth_form.html">mod_auth_form</a></code> module for documentation and complete + examples.</p> + + </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="integration" id="integration">Integrating Sessions with External Applications</a></h2> + + <p>In order for sessions to be useful, it must be possible to share the contents + of a session with external applications, and it must be possible for an + external application to write a session of its own.</p> + + <p> A typical example might be an application that changes a user's password set by + <code class="module"><a href="../mod/mod_auth_form.html">mod_auth_form</a></code>. This application would need to read the current + username and password from the session, make the required changes to the user's + password, and then write the new password to the session in order to provide a + seamless transition to the new password.</p> + + <p>A second example might involve an application that registers a new user for + the first time. When registration is complete, the username and password is + written to the session, providing a seamless transition to being logged in.</p> + + <dl> + <dt>Apache modules</dt> + <dd>Modules within the server that need access to the session can use the + <strong>mod_session.h</strong> API in order to read from and write to the + session. This mechanism is used by modules like <code class="module"><a href="../mod/mod_auth_form.html">mod_auth_form</a></code>. + </dd> + + <dt>CGI programs and scripting languages</dt> + <dd>Applications that run within the webserver can optionally retrieve the + value of the session from the <strong>HTTP_SESSION</strong> environment + variable. The session should be encoded as a + <strong>application/x-www-form-urlencoded</strong> string as described by the + <a href="http://www.w3.org/TR/html4/">HTML specification</a>. The environment + variable is controlled by the setting of the + <code class="directive"><a href="#sessionenv">SessionEnv</a></code> directive. The session + can be written to by the script by returning a + <strong>application/x-www-form-urlencoded</strong> response header with a name + set by the <code class="directive"><a href="#sessionheader">SessionHeader</a></code> + directive. In both cases, any encryption or decryption, and the reading the + session from or writing the session to the chosen storage mechanism is handled + by the <code class="module"><a href="../mod/mod_session.html">mod_session</a></code> modules and corresponding configuration. + </dd> + + <dt>Applications behind <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code></dt> + <dd>If the <code class="directive"><a href="#sessionheader">SessionHeader</a></code> + directive is used to define an HTTP request header, the session, encoded as + a <strong>application/x-www-form-urlencoded</strong> string, will be made + available to the application. If the same header is provided in the response, + the value of this response header will be used to replace the session. As + above, any encryption or decryption, and the reading the session from or + writing the session to the chosen storage mechanism is handled by the + <code class="module"><a href="../mod/mod_session.html">mod_session</a></code> modules and corresponding configuration.</dd> + + <dt>Standalone applications</dt> + <dd>Applications might choose to manipulate the session outside the control + of the Apache HTTP server. In this case, it is the responsibility of the + application to read the session from the chosen storage mechanism, + decrypt the session, update the session, encrypt the session and write + the session to the chosen storage mechanism, as appropriate.</dd> + </dl> + + </div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="Session" id="Session">Session</a> <a name="session" id="session">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables a session for the current directory or location</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>Session On|Off</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Session Off</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#Override">Override:</a></th><td>AuthConfig</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_session</td></tr> +</table> + <p>The <code class="directive">Session</code> directive enables a session for the + directory or location container. Further directives control where the + session will be stored and how privacy is maintained.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="SessionEnv" id="SessionEnv">SessionEnv</a> <a name="sessionenv" id="sessionenv">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Control whether the contents of the session are written to the +<var>HTTP_SESSION</var> environment variable</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SessionEnv On|Off</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SessionEnv Off</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#Override">Override:</a></th><td>AuthConfig</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_session</td></tr> +</table> + <p>If set to <var>On</var>, the <code class="directive">SessionEnv</code> directive + causes the contents of the session to be written to a CGI environment + variable called <var>HTTP_SESSION</var>.</p> + + <p>The string is written in the URL query format, for example:</p> + + <div class="example"><p><code> + <code>key1=foo&key3=bar</code> + </code></p></div> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="SessionExclude" id="SessionExclude">SessionExclude</a> <a name="sessionexclude" id="sessionexclude">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Define URL prefixes for which a session is ignored</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SessionExclude <var>path</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>none</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#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_session</td></tr> +</table> + <p>The <code class="directive">SessionExclude</code> directive allows sessions to + be disabled relative to URL prefixes only. This can be used to make a + website more efficient, by targeting a more precise URL space for which + a session should be maintained. By default, all URLs within the directory + or location are included in the session. The + <code class="directive"><a href="#sessionexclude">SessionExclude</a></code> directive takes + precedence over the + <code class="directive"><a href="#sessioninclude">SessionInclude</a></code> directive.</p> + + <div class="warning"><h3>Warning</h3> + <p>This directive has a similar purpose to the <var>path</var> attribute + in HTTP cookies, but should not be confused with this attribute. This + directive does not set the <var>path</var> attribute, which must be + configured separately.</p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="SessionExpiryUpdateInterval" id="SessionExpiryUpdateInterval">SessionExpiryUpdateInterval</a> <a name="sessionexpiryupdateinterval" id="sessionexpiryupdateinterval">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Define the number of seconds a session's expiry may change without +the session being updated</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SessionExpiryUpdateInterval <var>interval</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SessionExpiryUpdateInterval 0 (always update)</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#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_session</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.4.41 and later</td></tr> +</table> + <p>The <code class="directive">SessionExpiryUpdateInterval</code> directive allows + sessions to avoid the cost associated with writing the session each request + when only the expiry time has changed. This can be used to make a website + more efficient or reduce load on a database when using + <code class="module"><a href="../mod/mod_session_dbd.html">mod_session_dbd</a></code>. The session is always written if the data + stored in the session has changed or the expiry has changed by more than the + configured interval.</p> + + <p>Setting the interval to zero disables this directive, and the session + expiry is refreshed for each request.</p> + + <p>This directive only has an effect when combined with + <code class="directive"><a href="#sessionmaxage">SessionMaxAge</a></code> to enable session + expiry. Sessions without an expiry are only written when the data stored in + the session has changed.</p> + + <div class="warning"><h3>Warning</h3> + <p>Because the session expiry may not be refreshed with each request, it's + possible for sessions to expire up to <var>interval</var> seconds early. + Using a small interval usually provides sufficient savings while having a + minimal effect on expiry resolution.</p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="SessionHeader" id="SessionHeader">SessionHeader</a> <a name="sessionheader" id="sessionheader">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Import session updates from a given HTTP response header</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SessionHeader <var>header</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>none</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#Override">Override:</a></th><td>AuthConfig</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_session</td></tr> +</table> + <p>The <code class="directive">SessionHeader</code> directive defines the name of an + HTTP response header which, if present, will be parsed and written to the + current session.</p> + + <p>The header value is expected to be in the URL query format, for example:</p> + + <div class="example"><p><code> + <code>key1=foo&key2=&key3=bar</code> + </code></p></div> + + <p>Where a key is set to the empty string, that key will be removed from the + session.</p> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="SessionInclude" id="SessionInclude">SessionInclude</a> <a name="sessioninclude" id="sessioninclude">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Define URL prefixes for which a session is valid</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SessionInclude <var>path</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>all URLs</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#Override">Override:</a></th><td>AuthConfig</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_session</td></tr> +</table> + <p>The <code class="directive">SessionInclude</code> directive allows sessions to + be made valid for specific URL prefixes only. This can be used to make a + website more efficient, by targeting a more precise URL space for which + a session should be maintained. By default, all URLs within the directory + or location are included in the session.</p> + + <div class="warning"><h3>Warning</h3> + <p>This directive has a similar purpose to the <var>path</var> attribute + in HTTP cookies, but should not be confused with this attribute. This + directive does not set the <var>path</var> attribute, which must be + configured separately.</p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="SessionMaxAge" id="SessionMaxAge">SessionMaxAge</a> <a name="sessionmaxage" id="sessionmaxage">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Define a maximum age in seconds for a session</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SessionMaxAge <var>maxage</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SessionMaxAge 0</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#Override">Override:</a></th><td>AuthConfig</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_session</td></tr> +</table> + <p>The <code class="directive">SessionMaxAge</code> directive defines a time limit + for which a session will remain valid. When a session is saved, this time + limit is reset and an existing session can be continued. If a session + becomes older than this limit without a request to the server to refresh + the session, the session will time out and be removed. Where a session is + used to stored user login details, this has the effect of logging the user + out automatically after the given time.</p> + + <p>Setting the maxage to zero disables session expiry.</p> + +</div> +</div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="../en/mod/mod_session.html" title="English"> en </a> | +<a href="../fr/mod/mod_session.html" hreflang="fr" rel="alternate" title="Français"> fr </a></p> +</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 by our moderators if they are either implemented or considered invalid/off-topic. 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