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authorRich Bowen <rbowen@apache.org>2015-04-15 16:35:10 +0000
committerRich Bowen <rbowen@apache.org>2015-04-15 16:35:10 +0000
commit9fed79814211668e00b799f50385a464a3bdbe6b (patch)
tree8852c66a37dfd64e16252424ec02a3d1a6ffc31b /docs/manual/mod/mod_headers.html.en
parent2f339e75b0f5b8c22b2eb89b4dad38414c1a460e (diff)
downloadhttpd-9fed79814211668e00b799f50385a464a3bdbe6b.tar.gz
Rebuilds Daniel's change to the order of directictives vs topics in
manual docs git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1673855 13f79535-47bb-0310-9956-ffa450edef68
Diffstat (limited to 'docs/manual/mod/mod_headers.html.en')
-rw-r--r--docs/manual/mod/mod_headers.html.en304
1 files changed, 152 insertions, 152 deletions
diff --git a/docs/manual/mod/mod_headers.html.en b/docs/manual/mod/mod_headers.html.en
index 8b22e094bd..7a5a45a704 100644
--- a/docs/manual/mod/mod_headers.html.en
+++ b/docs/manual/mod/mod_headers.html.en
@@ -52,158 +52,6 @@ headers</td></tr>
<li><img alt="" src="../images/down.gif" /> <a href="#examples">Examples</a></li>
</ul><ul class="seealso"><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="order" id="order">Order of Processing</a></h2>
-
- <p>The directives provided by <code class="module"><a href="../mod/mod_headers.html">mod_headers</a></code> can
- occur almost anywhere within the server configuration, and can be
- limited in scope by enclosing them in <a href="../sections.html">configuration sections</a>.</p>
-
- <p>Order of processing is important and is affected both by the
- order in the configuration file and by placement in <a href="../sections.html#mergin">configuration sections</a>. These
- two directives have a different effect if reversed:</p>
-
- <pre class="prettyprint lang-config">RequestHeader append MirrorID "mirror 12"
-RequestHeader unset MirrorID</pre>
-
-
- <p>This way round, the <code>MirrorID</code> header is not set. If
- reversed, the MirrorID header is set to "mirror 12".</p>
-</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
-<div class="section">
-<h2><a name="early" id="early">Early and Late Processing</a></h2>
- <p><code class="module"><a href="../mod/mod_headers.html">mod_headers</a></code> can be applied either early or late
- in the request. The normal mode is late, when <em>Request</em> Headers are
- set immediately before running the content generator and <em>Response</em>
- Headers just as the response is sent down the wire. Always use
- Late mode in an operational server.</p>
-
- <p>Early mode is designed as a test/debugging aid for developers.
- Directives defined using the <code>early</code> keyword are set
- right at the beginning of processing the request. This means
- they can be used to simulate different requests and set up test
- cases, but it also means that headers may be changed at any time
- by other modules before generating a Response.</p>
-
- <p>Because early directives are processed before the request path's
- configuration is traversed, early headers can only be set in a
- main server or virtual host context. Early directives cannot depend
- on a request path, so they will fail in contexts such as
- <code class="directive"><a href="../mod/core.html#directory">&lt;Directory&gt;</a></code> or
- <code class="directive"><a href="../mod/core.html#location">&lt;Location&gt;</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="examples" id="examples">Examples</a></h2>
-
- <ol>
- <li>
- Copy all request headers that begin with "TS" to the
- response headers:
-
- <pre class="prettyprint lang-config">Header echo ^TS</pre>
-
- </li>
-
- <li>
- Add a header, <code>MyHeader</code>, to the response including a
- timestamp for when the request was received and how long it
- took to begin serving the request. This header can be used by
- the client to intuit load on the server or in isolating
- bottlenecks between the client and the server.
-
- <pre class="prettyprint lang-config">Header set MyHeader "%D %t"</pre>
-
-
- <p>results in this header being added to the response:</p>
-
- <div class="example"><p><code>
- MyHeader: D=3775428 t=991424704447256
- </code></p></div>
- </li>
-
- <li>
- Say hello to Joe
-
- <pre class="prettyprint lang-config">Header set MyHeader "Hello Joe. It took %D microseconds for Apache to serve this request."</pre>
-
-
- <p>results in this header being added to the response:</p>
-
- <div class="example"><p><code>
- MyHeader: Hello Joe. It took D=3775428 microseconds for Apache
- to serve this request.
- </code></p></div>
- </li>
-
- <li>
- Conditionally send <code>MyHeader</code> on the response if and
- only if header <code>MyRequestHeader</code> is present on the request.
- This is useful for constructing headers in response to some client
- stimulus. Note that this example requires the services of the
- <code class="module"><a href="../mod/mod_setenvif.html">mod_setenvif</a></code> module.
-
- <pre class="prettyprint lang-config">SetEnvIf MyRequestHeader myvalue HAVE_MyRequestHeader
-Header set MyHeader "%D %t mytext" env=HAVE_MyRequestHeader</pre>
-
-
- <p>If the header <code>MyRequestHeader: myvalue</code> is present on
- the HTTP request, the response will contain the following header:</p>
-
- <div class="example"><p><code>
- MyHeader: D=3775428 t=991424704447256 mytext
- </code></p></div>
- </li>
-
- <li>
- Enable DAV to work with Apache running HTTP through SSL hardware
- (<a href="http://svn.haxx.se/users/archive-2006-03/0549.shtml">problem
- description</a>) by replacing <var>https:</var> with
- <var>http:</var> in the <var>Destination</var> header:
-
- <pre class="prettyprint lang-config">RequestHeader edit Destination ^https: http: early</pre>
-
- </li>
-
- <li>
- Set the same header value under multiple nonexclusive conditions,
- but do not duplicate the value in the final header.
- If all of the following conditions applied to a request (i.e.,
- if the <code>CGI</code>, <code>NO_CACHE</code> and
- <code>NO_STORE</code> environment variables all existed for the
- request):
-
- <pre class="prettyprint lang-config">Header merge Cache-Control no-cache env=CGI
-Header merge Cache-Control no-cache env=NO_CACHE
-Header merge Cache-Control no-store env=NO_STORE</pre>
-
-
- <p>then the response would contain the following header:</p>
-
- <div class="example"><p><code>
- Cache-Control: no-cache, no-store
- </code></p></div>
-
- <p>If <code>append</code> was used instead of <code>merge</code>,
- then the response would contain the following header:</p>
-
- <div class="example"><p><code>
- Cache-Control: no-cache, no-cache, no-store
- </code></p></div>
- </li>
- <li>
- Set a test cookie if and only if the client didn't send us a cookie
- <pre class="prettyprint lang-config">Header set Set-Cookie testcookie "expr=-z %{req:Cookie}"</pre>
-
- </li>
- <li>
- Append a Caching header for responses with a HTTP status code of 200
- <pre class="prettyprint lang-config">Header append Cache-Control s-maxage=600 "expr=%{REQUEST_STATUS} == 200"</pre>
-
- </li>
-
- </ol>
-</div>
-<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="Header" id="Header">Header</a> <a name="header" id="header">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configure HTTP response headers</td></tr>
@@ -544,6 +392,158 @@ available in 2.4.10 and later</td></tr>
input filters to be overridden or modified.</p>
</div>
+<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="order" id="order">Order of Processing</a></h2>
+
+ <p>The directives provided by <code class="module"><a href="../mod/mod_headers.html">mod_headers</a></code> can
+ occur almost anywhere within the server configuration, and can be
+ limited in scope by enclosing them in <a href="../sections.html">configuration sections</a>.</p>
+
+ <p>Order of processing is important and is affected both by the
+ order in the configuration file and by placement in <a href="../sections.html#mergin">configuration sections</a>. These
+ two directives have a different effect if reversed:</p>
+
+ <pre class="prettyprint lang-config">RequestHeader append MirrorID "mirror 12"
+RequestHeader unset MirrorID</pre>
+
+
+ <p>This way round, the <code>MirrorID</code> header is not set. If
+ reversed, the MirrorID header is set to "mirror 12".</p>
+</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="early" id="early">Early and Late Processing</a></h2>
+ <p><code class="module"><a href="../mod/mod_headers.html">mod_headers</a></code> can be applied either early or late
+ in the request. The normal mode is late, when <em>Request</em> Headers are
+ set immediately before running the content generator and <em>Response</em>
+ Headers just as the response is sent down the wire. Always use
+ Late mode in an operational server.</p>
+
+ <p>Early mode is designed as a test/debugging aid for developers.
+ Directives defined using the <code>early</code> keyword are set
+ right at the beginning of processing the request. This means
+ they can be used to simulate different requests and set up test
+ cases, but it also means that headers may be changed at any time
+ by other modules before generating a Response.</p>
+
+ <p>Because early directives are processed before the request path's
+ configuration is traversed, early headers can only be set in a
+ main server or virtual host context. Early directives cannot depend
+ on a request path, so they will fail in contexts such as
+ <code class="directive"><a href="../mod/core.html#directory">&lt;Directory&gt;</a></code> or
+ <code class="directive"><a href="../mod/core.html#location">&lt;Location&gt;</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="examples" id="examples">Examples</a></h2>
+
+ <ol>
+ <li>
+ Copy all request headers that begin with "TS" to the
+ response headers:
+
+ <pre class="prettyprint lang-config">Header echo ^TS</pre>
+
+ </li>
+
+ <li>
+ Add a header, <code>MyHeader</code>, to the response including a
+ timestamp for when the request was received and how long it
+ took to begin serving the request. This header can be used by
+ the client to intuit load on the server or in isolating
+ bottlenecks between the client and the server.
+
+ <pre class="prettyprint lang-config">Header set MyHeader "%D %t"</pre>
+
+
+ <p>results in this header being added to the response:</p>
+
+ <div class="example"><p><code>
+ MyHeader: D=3775428 t=991424704447256
+ </code></p></div>
+ </li>
+
+ <li>
+ Say hello to Joe
+
+ <pre class="prettyprint lang-config">Header set MyHeader "Hello Joe. It took %D microseconds for Apache to serve this request."</pre>
+
+
+ <p>results in this header being added to the response:</p>
+
+ <div class="example"><p><code>
+ MyHeader: Hello Joe. It took D=3775428 microseconds for Apache
+ to serve this request.
+ </code></p></div>
+ </li>
+
+ <li>
+ Conditionally send <code>MyHeader</code> on the response if and
+ only if header <code>MyRequestHeader</code> is present on the request.
+ This is useful for constructing headers in response to some client
+ stimulus. Note that this example requires the services of the
+ <code class="module"><a href="../mod/mod_setenvif.html">mod_setenvif</a></code> module.
+
+ <pre class="prettyprint lang-config">SetEnvIf MyRequestHeader myvalue HAVE_MyRequestHeader
+Header set MyHeader "%D %t mytext" env=HAVE_MyRequestHeader</pre>
+
+
+ <p>If the header <code>MyRequestHeader: myvalue</code> is present on
+ the HTTP request, the response will contain the following header:</p>
+
+ <div class="example"><p><code>
+ MyHeader: D=3775428 t=991424704447256 mytext
+ </code></p></div>
+ </li>
+
+ <li>
+ Enable DAV to work with Apache running HTTP through SSL hardware
+ (<a href="http://svn.haxx.se/users/archive-2006-03/0549.shtml">problem
+ description</a>) by replacing <var>https:</var> with
+ <var>http:</var> in the <var>Destination</var> header:
+
+ <pre class="prettyprint lang-config">RequestHeader edit Destination ^https: http: early</pre>
+
+ </li>
+
+ <li>
+ Set the same header value under multiple nonexclusive conditions,
+ but do not duplicate the value in the final header.
+ If all of the following conditions applied to a request (i.e.,
+ if the <code>CGI</code>, <code>NO_CACHE</code> and
+ <code>NO_STORE</code> environment variables all existed for the
+ request):
+
+ <pre class="prettyprint lang-config">Header merge Cache-Control no-cache env=CGI
+Header merge Cache-Control no-cache env=NO_CACHE
+Header merge Cache-Control no-store env=NO_STORE</pre>
+
+
+ <p>then the response would contain the following header:</p>
+
+ <div class="example"><p><code>
+ Cache-Control: no-cache, no-store
+ </code></p></div>
+
+ <p>If <code>append</code> was used instead of <code>merge</code>,
+ then the response would contain the following header:</p>
+
+ <div class="example"><p><code>
+ Cache-Control: no-cache, no-cache, no-store
+ </code></p></div>
+ </li>
+ <li>
+ Set a test cookie if and only if the client didn't send us a cookie
+ <pre class="prettyprint lang-config">Header set Set-Cookie testcookie "expr=-z %{req:Cookie}"</pre>
+
+ </li>
+ <li>
+ Append a Caching header for responses with a HTTP status code of 200
+ <pre class="prettyprint lang-config">Header append Cache-Control s-maxage=600 "expr=%{REQUEST_STATUS} == 200"</pre>
+
+ </li>
+
+ </ol>
+</div>
</div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="../en/mod/mod_headers.html" title="English">&nbsp;en&nbsp;</a> |