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Posted to commits@sling.apache.org by bu...@apache.org on 2015/07/06 10:23:57 UTC
svn commit: r957178 - in /websites/staging/sling/trunk/content: ./
documentation/the-sling-engine/errorhandling.html
Author: buildbot
Date: Mon Jul 6 08:23:56 2015
New Revision: 957178
Log:
Staging update by buildbot for sling
Modified:
websites/staging/sling/trunk/content/ (props changed)
websites/staging/sling/trunk/content/documentation/the-sling-engine/errorhandling.html
Propchange: websites/staging/sling/trunk/content/
------------------------------------------------------------------------------
--- cms:source-revision (original)
+++ cms:source-revision Mon Jul 6 08:23:56 2015
@@ -1 +1 @@
-1688837
+1689335
Modified: websites/staging/sling/trunk/content/documentation/the-sling-engine/errorhandling.html
==============================================================================
--- websites/staging/sling/trunk/content/documentation/the-sling-engine/errorhandling.html (original)
+++ websites/staging/sling/trunk/content/documentation/the-sling-engine/errorhandling.html Mon Jul 6 08:23:56 2015
@@ -39,7 +39,18 @@
</div>
<div class="menu">
- <p><strong><a href="/documentation.html">Documentation</a></strong> <br />
+ <style type="text/css">
+/* The following code is added by mdx_elementid.py
+ It was originally lifted from http://subversion.apache.org/style/site.css */
+/*
+ * Hide class="elementid-permalink", except when an enclosing heading
+ * has the :hover property.
+ */
+.headerlink, .elementid-permalink {
+ visibility: hidden;
+}
+h2:hover > .headerlink, h3:hover > .headerlink, h1:hover > .headerlink, h6:hover > .headerlink, h4:hover > .headerlink, h5:hover > .headerlink, dt:hover > .elementid-permalink { visibility: visible }</style>
+<p><strong><a href="/documentation.html">Documentation</a></strong> <br />
<a href="/documentation/getting-started.html">Getting Started</a> <br />
<a href="/documentation/the-sling-engine.html">The Sling Engine</a> <br />
<a href="/documentation/development.html">Development</a> <br />
@@ -90,9 +101,22 @@
<h1>Errorhandling</h1>
- <p>The Sling Engine includes support for handling uncaught <code>Throwable</code> as well as rendering custom HTTP status code pages. This is implemented by expecting a (single) <code>org.apache.sling.engine.servlets.ErrorHandler</code> service to which handling of uncaught <code>Throwable</code> and HTTP status responses are delegated.</p>
+ <style type="text/css">
+/* The following code is added by mdx_elementid.py
+ It was originally lifted from http://subversion.apache.org/style/site.css */
+/*
+ * Hide class="elementid-permalink", except when an enclosing heading
+ * has the :hover property.
+ */
+.headerlink, .elementid-permalink {
+ visibility: hidden;
+}
+h2:hover > .headerlink, h3:hover > .headerlink, h1:hover > .headerlink, h6:hover > .headerlink, h4:hover > .headerlink, h5:hover > .headerlink, dt:hover > .elementid-permalink { visibility: visible }</style>
+<p>The Sling Engine includes support for handling uncaught <code>Throwable</code> as well as rendering custom HTTP status code pages. This is implemented by expecting a (single) <code>org.apache.sling.engine.servlets.ErrorHandler</code> service to which handling of uncaught <code>Throwable</code> and HTTP status responses are delegated.</p>
<p>The Sling Servlet Resolver bundle implements this interface by providing an elaborate mechanism to find the correct error handling script or servlet using the same algorithms as are used to select the scripts or servlets to handle regular requests.</p>
<p>This page provides more information on how error handler scripts are selected and what is provided out of the box.</p>
+<p>The <a href="https://svn.apache.org/repos/asf/sling/trunk/launchpad/integration-tests/src/main/java/org/apache/sling/launchpad/webapp/integrationtest/servlets/resolver/errorhandler/ErrorHandlingTest.java">ErrorHandlingTest</a> in our integration tests suite provides
+working examples of various error handling scenarios.</p>
<div class="toc">
<ul>
<li><a href="#resetting-the-response">Resetting the Response</a></li>
@@ -101,7 +125,7 @@
<li><a href="#default-handler">Default Handler</a></li>
</ul>
</div>
-<h2 id="resetting-the-response">Resetting the Response</h2>
+<h2 id="resetting-the-response">Resetting the Response<a class="headerlink" href="#resetting-the-response" title="Permanent link">¶</a></h2>
<p>Errorhandler scripts and servlets are script with the current response. Before setting
the status and writing to the response such handlers should do the following:</p>
<ul>
@@ -118,7 +142,7 @@ the status and writing to the response s
</ul>
</li>
</ul>
-<h2 id="http-status-codes">HTTP Status Codes</h2>
+<h2 id="http-status-codes">HTTP Status Codes<a class="headerlink" href="#http-status-codes" title="Permanent link">¶</a></h2>
<p>The Sling engine implements the <code>HttpServletResponse.sendError</code> methods by calling the <code>ErrorHandler.handleError(int status, String message, SlingHttpServletRequest request, SlingHttpServletResponse response)</code> method.</p>
<p>The Servlet Resolver bundle implementation looks up a script to handle the status code as follows:</p>
<ul>
@@ -130,12 +154,12 @@ the status and writing to the response s
<li>An application provider my provide a default handler for the 404/NOT FOUND status. This script might be located in <code>/libs/sling/servlet/errorhandler/404.jsp</code>.</li>
<li>An programmer might provide a handler for the 403/FORBIDDEN status in <code>/apps/sling/servlet/errorhandler/403.esp</code>.</li>
</ul>
-<h2 id="uncaught-throwables">Uncaught Throwables</h2>
+<h2 id="uncaught-throwables">Uncaught Throwables<a class="headerlink" href="#uncaught-throwables" title="Permanent link">¶</a></h2>
<p>To handle uncaught Throwables the simple name (<code>Class.getSimpleName()</code>) of the <code>Throwable</code> class is used as request extension. Similarly to the Java try-catch clauses the class hierarchy is supported. That is to handle an uncaught <code>FileNotFoundException</code>, the names <code>FileNotFoundException</code>, <code>IOException</code>, <code>Exception</code>, <code>Throwable</code> are checked for a Servlet and the first one found is then used. Again, the Serlvet may be a Servlet registered as an OSGi service or may be a plain script stored in the JCR repository or provided through some custom Resource provider.</p>
<p><strong>Example:</strong>
To register a catch-all handler for any uncaught Throwables you might create a script <code>/apps/sling/servlet/errorhandler/Throwable.esp</code>.</p>
<p><strong>Note:</strong> If no script or servlet to handle an uncaught <code>Throwable</code> is registered, the default handler kicks in, which sends back a 500/INTERNAL SERVER ERROR response containing the <code>Throwable</code> and the stack trace. This response is <strong>not</strong> handled by the HTTP Status Code handling described above because the response status is sent using <code>HttpServletResponse.setStatus(int, String)</code>. To prevent this default response you have to implement a catch-all handler for the <code>Throwable</code> class as shown in the example.</p>
-<h2 id="default-handler">Default Handler</h2>
+<h2 id="default-handler">Default Handler<a class="headerlink" href="#default-handler" title="Permanent link">¶</a></h2>
<p>The Sling Servlet Resolver bundle provides a default error handler servlet which is used if the algorithms described above do not resolve to a handler script or servlet. The provided error handler servlet does the following:</p>
<ul>
<li>Print a descriptive message, which is the <code>javax.servlet.error.message</code> request attribute by default</li>
@@ -145,7 +169,7 @@ To register a catch-all handler for any
<p>Starting with Sling Servlet Resolver version 2.0.10 the default error handler servlet is looked up using the string <code>default</code> as the request extension and the provided default servlet is registered as <code><prefix>/sling/servlet/errorhandler/default.servlet</code> where <prefix> is the last entry in the resource resolver search path, <code>/libs</code> by default.</p>
<p>Thus to overwrite the default error handler servlet provide a servlet or script for the <code>default</code> extension, for example <code>/apps/sling/servlet/errorhandler/default.groovy</code>.</p>
<div class="timestamp" style="margin-top: 30px; font-size: 80%; text-align: right;">
- Rev. 1500501 by fmeschbe on Sun, 7 Jul 2013 18:49:51 +0000
+ Rev. 1689335 by bdelacretaz on Mon, 6 Jul 2015 08:23:41 +0000
</div>
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