docker-app/test.dockerapp/tomcat/webapps/docs/default-servlet.html

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</script></head><body><div id="wrapper"><header><div id="header"><div><div><div class="logo noPrint"><a href="https://tomcat.apache.org/"><img alt="Tomcat Home" src="./images/tomcat.png"></a></div><div style="height: 1px;"></div><div class="asfLogo noPrint"><a href="https://www.apache.org/" target="_blank"><img src="./images/asf-logo.svg" alt="The Apache Software Foundation" style="width: 266px; height: 83px;"></a></div><h1>Apache Tomcat 8</h1><div class="versionInfo">
Version 8.0.53,
<time datetime="2018-06-29">Jun 29 2018</time></div><div style="height: 1px;"></div><div style="clear: left;"></div></div></div></div></header><div id="middle"><div><div id="mainLeft" class="noprint"><div><nav><div><h2>Links</h2><ul><li><a href="index.html">Docs Home</a></li><li><a href="https://wiki.apache.org/tomcat/FAQ">FAQ</a></li><li><a href="#comments_section">User Comments</a></li></ul></div><div><h2>User Guide</h2><ul><li><a href="introduction.html">1) Introduction</a></li><li><a href="setup.html">2) Setup</a></li><li><a href="appdev/index.html">3) First webapp</a></li><li><a href="deployer-howto.html">4) Deployer</a></li><li><a href="manager-howto.html">5) Manager</a></li><li><a href="host-manager-howto.html">6) Host Manager</a></li><li><a href="realm-howto.html">7) Realms and AAA</a></li><li><a href="security-manager-howto.html">8) Security Manager</a></li><li><a href="jndi-resources-howto.html">9) JNDI Resources</a></li><li><a href="jndi-datasource-examples-howto.html">10) JDBC DataSources</a></li><li><a href="class-loader-howto.html">11) Classloading</a></li><li><a href="jasper-howto.html">12) JSPs</a></li><li><a href="ssl-howto.html">13) SSL/TLS</a></li><li><a href="ssi-howto.html">14) SSI</a></li><li><a href="cgi-howto.html">15) CGI</a></li><li><a href="proxy-howto.html">16) Proxy Support</a></li><li><a href="mbeans-descriptors-howto.html">17) MBeans Descriptors</a></li><li><a href="default-servlet.html">18) Default Servlet</a></li><li><a href="cluster-howto.html">19) Clustering</a></li><li><a href="balancer-howto.html">20) Load Balancer</a></li><li><a href="connectors.html">21) Connectors</a></li><li><a href="monitoring.html">22) Monitoring and Management</a></li><li><a href="logging.html">23) Logging</a></li><li><a href="apr.html">24) APR/Native</a></li><li><a href="virtual-hosting-howto.html">25) Virtual Hosting</a></li><li><a href="aio.html">26) Advanced IO</a></li><li><a href="extras.html">27) Additional Components</a></li><li><a href="maven-jars.html">28) Mavenized</a></li><li><a href="security-howto.html">29) Security Considerations</a></li><li><a href="windows-service-howto.html">30) Windows Service</a></li><li><a href="windows-auth-howto.html">31) Windows Authentication</a></li><li><a href="jdbc-pool.html">32) Tomcat's JDBC Pool</a></li><li><a href="web-socket-howto.html">33) WebSocket</a></li><li><a href="rewrite.html">34) Rewrite</a></li></ul></div><div><h2>Reference</h2><ul><li><a href="RELEASE-NOTES.txt">Release Notes</a></li><li><a href="config/index.html">Configuration</a></li><li><a href="api/index.html">Tomcat Javadocs</a></li><li><a href="servletapi/index.html">Servlet Javadocs</a></li><li><a href="jspapi/index.html">JSP 2.3 Javadocs</a></li><li><a href="elapi/index.html">EL 3.0 Javadocs</a></li><li><a href="websocketapi/index.html">WebSocket 1.1 Javadocs</a></li><li><a href="https://tomcat.apache.org/connectors-doc/">JK 1.2 Documentation</a></li></ul></div><div><h2>Apache Tomcat Development</h2><ul><li><a href="building.html">Building</a></li><li><a href="changelog.html">Changelog</a></li><li><a href="https://wiki.apache.org/tomcat/TomcatVersions">Status</a></li><li><a href="developers.html">Developers</a></li><li><a href="architecture/index.html">Architecture</a></li><li><a href="funcspecs/index.html">Functional Specs.</a></li><li><a href="tribes/introduction.html">Tribes</a></li></ul></div></nav></div></div><div id="mainRight"><div id="content"><h2>Default Servlet Reference</h2><h3 id="Table_of_Contents">Table of Contents</h3><div class="text">
<ul><li><a href="#what">What is the DefaultServlet</a></li><li><a href="#where">Where is it declared?</a></li><li><a href="#change">What can I change?</a></li><li><a href="#dir">How do I customize directory listings?</a></li><li><a href="#secure">How do I secure directory listings?</a></li></ul>
</div><h3 id="what">What is the DefaultServlet</h3><div class="text">
<p>
The default servlet is the servlet which serves static resources as well
as serves the directory listings (if directory listings are enabled).
</p>
</div><h3 id="where">Where is it declared?</h3><div class="text">
<p>
It is declared globally in <i>$CATALINA_BASE/conf/web.xml</i>.
By default here is it's declaration:
</p>
<div class="codeBox"><pre><code> &lt;servlet&gt;
&lt;servlet-name&gt;default&lt;/servlet-name&gt;
&lt;servlet-class&gt;
org.apache.catalina.servlets.DefaultServlet
&lt;/servlet-class&gt;
&lt;init-param&gt;
&lt;param-name&gt;debug&lt;/param-name&gt;
&lt;param-value&gt;0&lt;/param-value&gt;
&lt;/init-param&gt;
&lt;init-param&gt;
&lt;param-name&gt;listings&lt;/param-name&gt;
&lt;param-value&gt;false&lt;/param-value&gt;
&lt;/init-param&gt;
&lt;load-on-startup&gt;1&lt;/load-on-startup&gt;
&lt;/servlet&gt;
...
&lt;servlet-mapping&gt;
&lt;servlet-name&gt;default&lt;/servlet-name&gt;
&lt;url-pattern&gt;/&lt;/url-pattern&gt;
&lt;/servlet-mapping&gt;</code></pre></div>
So by default, the default servlet is loaded at webapp startup and
directory listings are disabled and debugging is turned off.
</div><h3 id="change">What can I change?</h3><div class="text">
<p>
The DefaultServlet allows the following initParamters:
</p>
<table class="defaultTable"><tr><th style="width: 15%;">
Property
</th><th style="width: 85%;">
Description
</th></tr><tr><td><code class="propertyName">debug</code></td><td>
Debugging level. It is not very useful unless you are a tomcat
developer. As
of this writing, useful values are 0, 1, 11, 1000. [0]
</td></tr><tr><td><code class="propertyName">listings</code></td><td>
If no welcome file is present, can a directory listing be
shown?
value may be <b>true</b> or <b>false</b> [false]
<br>
Welcome files are part of the servlet api.
<br>
<b>WARNING:</b> Listings of directories containing many entries are
expensive. Multiple requests for large directory listings can consume
significant proportions of server resources.
</td></tr><tr><td><code class="propertyName">gzip</code></td><td>
If a gzipped version of a file exists (a file with <code>.gz</code>
appended to the file name located alongside the original file), Tomcat
will serve the gzipped file if the user agent supports gzip and this
option is enabled. [false]
<br>
The file with the <code>.gz</code> extension will be accessible if
requested directly so if the original resource is protected with a
security constraint, the gzipped version must be similarly protected.
</td></tr><tr><td><code class="propertyName">readmeFile</code></td><td>
If a directory listing is presented, a readme file may also
be presented with the listing. This file is inserted as is
so it may contain HTML.
</td></tr><tr><td><code class="propertyName">globalXsltFile</code></td><td>
If you wish to customize your directory listing, you
can use an XSL transformation. This value is a relative file name (to
either $CATALINA_BASE/conf/ or $CATALINA_HOME/conf/) which will be used
for all directory listings. This can be overridden per context and/or
per directory. See <strong>contextXsltFile</strong> and
<strong>localXsltFile</strong> below. The format of the xml is shown
below.
</td></tr><tr><td><code class="propertyName">contextXsltFile</code></td><td>
You may also customize your directory listing by context by
configuring <code>contextXsltFile</code>. This must be a context
relative path (e.g.: <code>/path/to/context.xslt</code>) to a file with
a <code>.xsl</code> or <code>.xslt</code> extension. This overrides
<code>globalXsltFile</code>. If this value is present but a file does
not exist, then <code>globalXsltFile</code> will be used. If
<code>globalXsltFile</code> does not exist, then the default
directory listing will be shown.
</td></tr><tr><td><code class="propertyName">localXsltFile</code></td><td>
You may also customize your directory listing by directory by
configuring <code>localXsltFile</code>. This must be a file in the
directory where the listing will take place to with a
<code>.xsl</code> or <code>.xslt</code> extension. This overrides
<code>globalXsltFile</code> and <code>contextXsltFile</code>. If this
value is present but a file does not exist, then
<code>contextXsltFile</code> will be used. If
<code>contextXsltFile</code> does not exist, then
<code>globalXsltFile</code> will be used. If
<code>globalXsltFile</code> does not exist, then the default
directory listing will be shown.
</td></tr><tr><td><code class="propertyName">input</code></td><td>
Input buffer size (in bytes) when reading
resources to be served. [2048]
</td></tr><tr><td><code class="propertyName">output</code></td><td>
Output buffer size (in bytes) when writing
resources to be served. [2048]
</td></tr><tr><td><code class="propertyName">readonly</code></td><td>
Is this context "read only", so HTTP commands like PUT and
DELETE are rejected? [true]
</td></tr><tr><td><code class="propertyName">fileEncoding</code></td><td>
File encoding to be used when reading static resources.
[platform default]
</td></tr><tr><td><code class="propertyName">sendfileSize</code></td><td>
If the connector used supports sendfile, this represents the minimal
file size in KB for which sendfile will be used. Use a negative value
to always disable sendfile. [48]
</td></tr><tr><td><code class="propertyName">useAcceptRanges</code></td><td>
If true, the Accept-Ranges header will be set when appropriate for the
response. [true]
</td></tr><tr><td><code class="propertyName">showServerInfo</code></td><td>
Should server information be presented in the response sent to clients
when directory listing is enabled. [true]
</td></tr></table>
</div><h3 id="dir">How do I customize directory listings?</h3><div class="text">
<p>You can override DefaultServlet with you own implementation and use that
in your web.xml declaration. If you
can understand what was just said, we will assume you can read the code
to DefaultServlet servlet and make the appropriate adjustments. (If not,
then that method isn't for you)
</p>
<p>
You can use either <code>localXsltFile</code> or
<code>globalXsltFile</code> and DefaultServlet will create
an xml document and run it through an xsl transformation based
on the values provided in <code>localXsltFile</code> and
<code>globalXsltFile</code>. <code>localXsltFile</code> is first
checked, followed by <code>globalXsltFile</code>, then default
behaviors takes place.
</p>
<p>
Format:
</p>
<div class="codeBox"><pre><code> &lt;listing&gt;
&lt;entries&gt;
&lt;entry type='file|dir' urlPath='aPath' size='###' date='gmt date'&gt;
fileName1
&lt;/entry&gt;
&lt;entry type='file|dir' urlPath='aPath' size='###' date='gmt date'&gt;
fileName2
&lt;/entry&gt;
...
&lt;/entries&gt;
&lt;readme&gt;&lt;/readme&gt;
&lt;/listing&gt;</code></pre></div>
<ul>
<li>size will be missing if <code>type='dir'</code></li>
<li>Readme is a CDATA entry</li>
</ul>
<p>
The following is a sample xsl file which mimics the default tomcat behavior:
</p>
<div class="codeBox"><pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="3.0"&gt;
&lt;xsl:output method="html" html-version="5.0"
encoding="UTF-8" indent="no"
doctype-system="about:legacy-compat"/&gt;
&lt;xsl:template match="listing"&gt;
&lt;html&gt;
&lt;head&gt;
&lt;title&gt;
Sample Directory Listing For
&lt;xsl:value-of select="@directory"/&gt;
&lt;/title&gt;
&lt;style&gt;
h1 {color : white;background-color : #0086b2;}
h3 {color : white;background-color : #0086b2;}
body {font-family : sans-serif,Arial,Tahoma;
color : black;background-color : white;}
b {color : white;background-color : #0086b2;}
a {color : black;} HR{color : #0086b2;}
table td { padding: 5px; }
&lt;/style&gt;
&lt;/head&gt;
&lt;body&gt;
&lt;h1&gt;Sample Directory Listing For
&lt;xsl:value-of select="@directory"/&gt;
&lt;/h1&gt;
&lt;hr style="height: 1px;" /&gt;
&lt;table style="width: 100%;"&gt;
&lt;tr&gt;
&lt;th style="text-align: left;"&gt;Filename&lt;/th&gt;
&lt;th style="text-align: center;"&gt;Size&lt;/th&gt;
&lt;th style="text-align: right;"&gt;Last Modified&lt;/th&gt;
&lt;/tr&gt;
&lt;xsl:apply-templates select="entries"/&gt;
&lt;/table&gt;
&lt;xsl:apply-templates select="readme"/&gt;
&lt;hr style="height: 1px;" /&gt;
&lt;h3&gt;Apache Tomcat/&lt;version-major-minor/&gt;&lt;/h3&gt;
&lt;/body&gt;
&lt;/html&gt;
&lt;/xsl:template&gt;
&lt;xsl:template match="entries"&gt;
&lt;xsl:apply-templates select="entry"/&gt;
&lt;/xsl:template&gt;
&lt;xsl:template match="readme"&gt;
&lt;hr style="height: 1px;" /&gt;
&lt;pre&gt;&lt;xsl:apply-templates/&gt;&lt;/pre&gt;
&lt;/xsl:template&gt;
&lt;xsl:template match="entry"&gt;
&lt;tr&gt;
&lt;td style="text-align: left;"&gt;
&lt;xsl:variable name="urlPath" select="@urlPath"/&gt;
&lt;a href="{$urlPath}"&gt;
&lt;pre&gt;&lt;xsl:apply-templates/&gt;&lt;/pre&gt;
&lt;/a&gt;
&lt;/td&gt;
&lt;td style="text-align: right;"&gt;
&lt;pre&gt;&lt;xsl:value-of select="@size"/&gt;&lt;/pre&gt;
&lt;/td&gt;
&lt;td style="text-align: right;"&gt;
&lt;pre&gt;&lt;xsl:value-of select="@date"/&gt;&lt;/pre&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/xsl:template&gt;
&lt;/xsl:stylesheet&gt;</code></pre></div>
</div><h3 id="secure">How do I secure directory listings?</h3><div class="text">
Use web.xml in each individual webapp. See the security section of the
Servlet specification.
</div><div class="noprint"><h3 id="comments_section">
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