documentation rebuild

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1844402 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/docs/manual/mod/core.html.en b/docs/manual/mod/core.html.en
index c66ea78d7dcca47435738fac58c1aa3eb77ab996..b5f9a03390a9a89705b2daf4016ce09bc414a155 100644 (file)
--- a/docs/manual/mod/core.html.en
+++ b/docs/manual/mod/core.html.en
@@ -821,7 +821,7 @@ headers</td></tr>
 <div class="directive-section"><h2><a name="DefaultStateDir" id="DefaultStateDir">DefaultStateDir</a> <a name="defaultstatedir" id="defaultstatedir">Directive</a><a title="Permanent link" href="#defaultstatedir" class="permalink">&para;</a></h2>
 <table class="directive">
 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Base directory for the persistent state files</td></tr>
-<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DefaultStateeDir <var>directory-path</var></code></td></tr>
+<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DefaultStateDir <var>directory-path</var></code></td></tr>
 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DefaultRuntimeDir DEFAULT_REL_STATEDIR (state/)</code></td></tr>
 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Core</td></tr>

diff --git a/docs/manual/mod/mod_headers.html.en b/docs/manual/mod/mod_headers.html.en
index cd8ae6974ee30d299fac47a02027f5db1c076ae0..45f5b87b584bed04ee7c3710fb939962f96d8da9 100644 (file)
--- a/docs/manual/mod/mod_headers.html.en
+++ b/docs/manual/mod/mod_headers.html.en
@@ -228,16 +228,12 @@ available in 2.4.10 and later</td></tr>
     modified.</p>
 
     <p> The optional <var>condition</var> argument determines which internal
-    table of responses headers this directive will operate against. Despite the
-    name, the default value of <code>onsuccess</code> does <em>not</em> limit
-    an <var>action</var> to responses with a 2xx status code.  Headers set under
-    this condition are still used when, for example, a request is <em>successfully</em>
-    proxied or generated by CGI, even when they have generated a failing status code.</p>
-
-    <p>When your action is a function of an existing header, you may need to specify
-    a condition of <code>always</code>, depending on which internal table the
-    original header was set in.  The table that corresponds to <code>always</code> is
-    used for locally generated error responses as well as successful responses.
+    table of responses headers this directive will operate against:
+    <code>onsuccess</code> (default, can be omitted) or <code>always</code>.
+    The difference between the two lists is that the headers contained in the
+    latter are added to the response even on error, and persisted across
+    internal redirects (for example, ErrorDocument handlers).
+
     Note also that repeating this directive with both conditions makes sense in
     some scenarios because <code>always</code> is not a superset of
     <code>onsuccess</code> with respect to existing headers:</p>
@@ -246,14 +242,40 @@ available in 2.4.10 and later</td></tr>
        <li> You're adding a header to a locally generated non-success (non-2xx) response, such
             as a redirect, in which case only the table corresponding to
             <code>always</code> is used in the ultimate response.</li>
-       <li> You're modifying or removing a header generated by a CGI script,
-            in which case the CGI scripts are in the table corresponding to
+       <li> You're modifying or removing a header generated by a CGI script
+            or by <code class="module"><a href="../mod/mod_proxy_fcgi.html">mod_proxy_fcgi</a></code>,
+            in which case the CGI scripts' headers are in the table corresponding to
             <code>always</code> and not in the default table.</li>
        <li> You're modifying or removing a header generated by some piece of
             the server but that header is not being found by the default
             <code>onsuccess</code> condition.</li>
     </ul>
 
+    <p>This difference between <code>onsuccess</code> and <code>always</code> is
+    a feature that resulted as a consequence of how httpd internally stores
+    headers for a HTTP response, since it does not offer any "normalized" single
+    list of headers. The main problem that can arise if the following concept
+    is not kept in mind while writing the configuration is that some HTTP responses
+    might end up with the same header duplicated (confusing users or sometimes even
+    HTTP clients). For example, suppose that you have a simple PHP proxy setup with
+    <code class="module"><a href="../mod/mod_proxy_fcgi.html">mod_proxy_fcgi</a></code> and your backend PHP scripts adds the
+    <code>X-Foo: bar</code> header to each HTTP response. As described above,
+    <code class="module"><a href="../mod/mod_proxy_fcgi.html">mod_proxy_fcgi</a></code> uses the <code>always</code> table to store
+    headers, so a configuration like the following ends up in the wrong result, namely
+    having the header duplicated with both values:</p>
+
+    <pre class="prettyprint lang-config"># X-Foo's value is set in the 'onsuccess' headers table
+Header set X-Foo: baz</pre>
+    
+
+    <p>To circumvent this limitation, there are some known configuration
+    patterns that can help, like the following:</p>
+
+        <pre class="prettyprint lang-config"># 'onsuccess' can be omitted since it is the default
+Header onsuccess unset X-Foo
+Header always set X-Foo "baz"</pre>
+
+
     <p>Separately from the <var>condition</var> parameter described above, you
     can limit an action based on HTTP status codes for e.g. proxied or CGI
     requests. See the example that uses %{REQUEST_STATUS} in the section above.</p>
@@ -262,6 +284,14 @@ available in 2.4.10 and later</td></tr>
     argument (second argument if a <var>condition</var> is specified).
     This can be one of the following values:</p>
 
+    <div class="warning"><h3>Warning</h3>
+        <p>Please read the difference between <code>always</code>
+        and <code>onsuccess</code> headers list described above
+        before start reading the actions list, since that important
+        concept still applies. Each action, in fact, works as described
+        but only on the target headers list.</p>
+    </div>
+
     <dl>
     <dt><code>add</code></dt>
     <dd>The response header is added to the existing set of headers,

diff --git a/docs/manual/mod/quickreference.html.en b/docs/manual/mod/quickreference.html.en
index 4a6249807f9aae6205533d8073945885cdfae293..e4943a3e0c914d1454329c294ccae827f639a99d 100644 (file)
--- a/docs/manual/mod/quickreference.html.en
+++ b/docs/manual/mod/quickreference.html.en
@@ -412,7 +412,7 @@ configured</td></tr>
 header field for all resources in the current context that have not been
 assigned a language-tag by some other means.</td></tr>
 <tr><td><a href="core.html#defaultruntimedir">DefaultRuntimeDir <var>directory-path</var></a></td><td> DEFAULT_REL_RUNTIME +</td><td>s</td><td>C</td></tr><tr><td class="descr" colspan="4">Base directory for the server run-time files</td></tr>
-<tr class="odd"><td><a href="core.html#defaultstatedir">DefaultStateeDir <var>directory-path</var></a></td><td></td><td>s</td><td>C</td></tr><tr class="odd"><td class="descr" colspan="4">Base directory for the persistent state files</td></tr>
+<tr class="odd"><td><a href="core.html#defaultstatedir">DefaultStateDir <var>directory-path</var></a></td><td></td><td>s</td><td>C</td></tr><tr class="odd"><td class="descr" colspan="4">Base directory for the persistent state files</td></tr>
 <tr><td><a href="core.html#defaulttype">DefaultType <var>media-type|none</var></a></td><td> none </td><td>svdh</td><td>C</td></tr><tr><td class="descr" colspan="4">This directive has no effect other than to emit warnings
 if the value is not <code>none</code>. In prior versions, DefaultType
 would specify a default media type to assign to response content for