diff options
| author | Jason McIntyre <jmc@cvs.openbsd.org> | 2005-07-29 23:55:41 +0000 |
|---|---|---|
| committer | Jason McIntyre <jmc@cvs.openbsd.org> | 2005-07-29 23:55:41 +0000 |
| commit | 4b50c27ec5ec786ab4022e61f94c0e58e969c883 (patch) | |
| tree | 5d9ad9804b385464c6c70e2f061f916929bc8ed5 /usr.sbin/httpd/htdocs/manual/custom-error.html | |
| parent | 4654fe49edf1731316a76df08f77c5ebe63b4b0b (diff) | |
from tamas tevesz:
==> de-multiviewification complete.
(rename *.html.html -> *.html)
Diffstat (limited to 'usr.sbin/httpd/htdocs/manual/custom-error.html')
| -rw-r--r-- | usr.sbin/httpd/htdocs/manual/custom-error.html | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/usr.sbin/httpd/htdocs/manual/custom-error.html b/usr.sbin/httpd/htdocs/manual/custom-error.html new file mode 100644 index 00000000000..bccb11a9a20 --- /dev/null +++ b/usr.sbin/httpd/htdocs/manual/custom-error.html @@ -0,0 +1,196 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml"> + <head> + <meta name="generator" content="HTML Tidy, see www.w3.org" /> + + <title>Custom error responses</title> + </head> + <!-- Background white, links blue (unvisited), navy (visited), red (active) --> + + <body bgcolor="#FFFFFF" text="#000000" link="#0000FF" + vlink="#000080" alink="#FF0000"> + <div align="CENTER"> + <img src="images/sub.gif" alt="[APACHE DOCUMENTATION]" /> + + <h3>Apache HTTP Server</h3> + </div> + + + + <h1 align="CENTER">Custom error responses</h1> + + <dl> + <dt>Purpose</dt> + + <dd> + Additional functionality. Allows webmasters to configure + the response of Apache to some error or problem. + + <p>Customizable responses can be defined to be activated in + the event of a server detected error or problem.</p> + + <p>e.g. if a script crashes and produces a "500 Server + Error" response, then this response can be replaced with + either some friendlier text or by a redirection to another + URL (local or external).</p> + </dd> + + <dt>Old behavior</dt> + + <dd>NCSA httpd 1.3 would return some boring old error/problem + message which would often be meaningless to the user, and + would provide no means of logging the symptoms which caused + it.<br /> + </dd> + + <dt>New behavior</dt> + + <dd> + The server can be asked to; + + <ol> + <li>Display some other text, instead of the NCSA hard + coded messages, or</li> + + <li>redirect to a local URL, or</li> + + <li>redirect to an external URL.</li> + </ol> + + <p>Redirecting to another URL can be useful, but only if + some information can be passed which can then be used to + explain and/or log the error/problem more clearly.</p> + + <p>To achieve this, Apache will define new CGI-like + environment variables, <em>e.g.</em></p> + + <blockquote> + <code>REDIRECT_HTTP_ACCEPT=*/*, image/gif, + image/x-xbitmap, image/jpeg<br /> + REDIRECT_HTTP_USER_AGENT=Mozilla/1.1b2 (X11; I; HP-UX + A.09.05 9000/712)<br /> + REDIRECT_PATH=.:/bin:/usr/local/bin:/etc<br /> + REDIRECT_QUERY_STRING=<br /> + REDIRECT_REMOTE_ADDR=121.345.78.123<br /> + REDIRECT_REMOTE_HOST=ooh.ahhh.com<br /> + REDIRECT_SERVER_NAME=crash.bang.edu<br /> + REDIRECT_SERVER_PORT=80<br /> + REDIRECT_SERVER_SOFTWARE=Apache/0.8.15<br /> + REDIRECT_URL=/cgi-bin/buggy.pl<br /> + </code> + </blockquote> + + <p>note the <code>REDIRECT_</code> prefix.</p> + + <p>At least <code>REDIRECT_URL</code> and + <code>REDIRECT_QUERY_STRING</code> will be passed to the + new URL (assuming it's a cgi-script or a cgi-include). The + other variables will exist only if they existed prior to + the error/problem. <strong>None</strong> of these will be + set if your ErrorDocument is an <em>external</em> redirect + (<em>i.e.</em>, anything starting with a scheme name like + <code>http:</code>, even if it refers to the same host as + the server).</p> + </dd> + + <dt>Configuration</dt> + + <dd> + Use of "ErrorDocument" is enabled for .htaccess files when + the <a href="mod/core.html#allowoverride">"FileInfo" + override</a> is allowed. + + <p>Here are some examples...</p> + + <blockquote> + <code>ErrorDocument 500 /cgi-bin/crash-recover<br /> + ErrorDocument 500 "Sorry, our script crashed. Oh + dear<br /> + ErrorDocument 500 http://xxx/<br /> + ErrorDocument 404 /Lame_excuses/not_found.html<br /> + ErrorDocument 401 + /Subscription/how_to_subscribe.html</code> + </blockquote> + + <p>The syntax is,</p> + + <p><code><a + href="mod/core.html#errordocument">ErrorDocument</a></code> + <3-digit-code> action</p> + + <p>where the action can be,</p> + + <ol> + <li>Text to be displayed. Prefix the text with a quote + ("). Whatever follows the quote is displayed. <em>Note: + the (") prefix isn't displayed.</em></li> + + <li>An external URL to redirect to.</li> + + <li>A local URL to redirect to.</li> + </ol> + </dd> + </dl> + <hr /> + + <h2>Custom error responses and redirects</h2> + + <dl> + <dt>Purpose</dt> + + <dd>Apache's behavior to redirected URLs has been modified so + that additional environment variables are available to a + script/server-include.</dd> + + <dt>Old behavior</dt> + + <dd>Standard CGI vars were made available to a script which + has been redirected to. No indication of where the + redirection came from was provided.</dd> + + <dt>New behavior</dt> + + <dd>A new batch of environment variables will be initialized + for use by a script which has been redirected to. Each new + variable will have the prefix <code>REDIRECT_</code>. + <code>REDIRECT_</code> environment variables are created from + the CGI environment variables which existed prior to the + redirect, they are renamed with a <code>REDIRECT_</code> + prefix, <em>i.e.</em>, <code>HTTP_USER_AGENT</code> becomes + <code>REDIRECT_HTTP_USER_AGENT</code>. In addition to these + new variables, Apache will define <code>REDIRECT_URL</code> + and <code>REDIRECT_STATUS</code> to help the script trace its + origin. Both the original URL and the URL being redirected to + can be logged in the access log.</dd> + </dl> + + <p>If the ErrorDocument specifies a local redirect to a CGI + script, the script should include a "<samp>Status:</samp>" + header field in its output in order to ensure the propagation + all the way back to the client of the error condition that + caused it to be invoked. For instance, a Perl ErrorDocument + script might include the following:</p> +<pre> + : + print "Content-type: text/html\n"; + printf "Status: %s Condition Intercepted\n", $ENV{"REDIRECT_STATUS"}; + : +</pre> + + <p>If the script is dedicated to handling a particular error + condition, such as <samp>404 Not Found</samp>, it can + use the specific code and error text instead.</p> + <hr /> + + <h3 align="CENTER">Apache HTTP Server</h3> + <a href="./"><img src="images/index.gif" alt="Index" /></a> + + </body> +</html> + + + |