i ProxySCGIInternalRedirect with alternate response header

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1678234 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/CHANGES b/CHANGES
index 9fce9fd41831af50203bb4f0a124948aceadc5d1..f22738d5339565fd3dee7dcbdeefc6619098bf0e 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -16,6 +16,11 @@ Changes with Apache 2.4.13
      rfc822Name and dNSName into SSL_{CLIENT,SERVER}_SAN_{Email,DNS}_n
      environment variables. Also addresses PR 57207. [Kaspar Brand]
 
+  *) mod_proxy_scgi: ProxySCGIInternalRedirect now allows an alternate
+     response header to be used by the application, for when the application
+     or framework is unable to return Location in the internal-redirect
+     form.  [Jeff Trawick]
+
   *) mpm_event: Allow for timer events duplicates. [Jim Jagielski, Yann Ylavic]
 
   *) mod_proxy, mod_ssl, mod_cache_socache, mod_socache_*: Support machine

diff --git a/STATUS b/STATUS
index 135b91f000b15a3adafc0685e14133ab99c77884..710c02865fe7fd0c76af8b81e3e52117181a02c4 100644 (file)
--- a/STATUS
+++ b/STATUS
@@ -105,15 +105,6 @@ RELEASE SHOWSTOPPERS:
 PATCHES ACCEPTED TO BACKPORT FROM TRUNK:
   [ start all new proposals below, under PATCHES PROPOSED. ]
 
-  *) mod_proxy_scgi: ProxySCGIInternalRedirect with alternate response header
-     trunk patch: 1674510
-     2.4.x patch: trunk works (modulo CHANGES)
-       This also needs <compatibility> in the doc moved down like in 
-           http://svn.apache.org/viewvc/httpd/httpd/trunk/docs/manual/mod/mod_proxy_scgi.xml?r1=1674510&r2=1674530&diff_format=h
-       and the version edited :)
-     Pre-edited: http://people.apache.org/~trawick/r1674510-to-2.4.x.txt
-     +1: trawick, jim, ylavic
-
    * mod_dav: Avoid some work that is unnecessary and often very time consuming.
      This helps mitigate Subversion issue #4531:
      http://subversion.tigris.org/issues/show_bug.cgi?id=4531

diff --git a/docs/manual/mod/mod_proxy_scgi.xml b/docs/manual/mod/mod_proxy_scgi.xml
index a5ebc7e7c76aceec4b5ed038dd6f12309bbfa877..79b4293c3897fbc8d2d2e9aa2b5af7fde38543bb 100644 (file)
--- a/docs/manual/mod/mod_proxy_scgi.xml
+++ b/docs/manual/mod/mod_proxy_scgi.xml
@@ -145,27 +145,35 @@ ProxySCGISendfile X-Send-Static
 <name>ProxySCGIInternalRedirect</name>
 <description>Enable or disable internal redirect responses from the
 backend</description>
-<syntax>ProxySCGIInternalRedirect On|Off</syntax>
+<syntax>ProxySCGIInternalRedirect On|Off|<var>Headername</var></syntax>
 <default>ProxySCGIInternalRedirect On</default>
 <contextlist><context>server config</context><context>virtual host</context>
 <context>directory</context></contextlist>
+<compatibility>The <var>Headername</var> feature is available in version
+2.4.13 and later</compatibility>
 
 <usage>
     <p>The <directive>ProxySCGIInternalRedirect</directive> enables the backend
     to internally redirect the gateway to a different URL. This feature
     originates in <module>mod_cgi</module>, which internally redirects the
     response if the response status is <code>OK</code> (<code>200</code>) and
-    the response contains a <code>Location</code> header and its value starts
-    with a slash (<code>/</code>). This value is interpreted as a new local
-    URL that Apache httpd internally redirects to.</p>
+    the response contains a <code>Location</code> (or configured alternate
+    header) and its value starts with a slash (<code>/</code>). This value is 
+    interpreted as a new local URL that Apache httpd internally redirects to.</p>
 
     <p><module>mod_proxy_scgi</module> does the same as
     <module>mod_cgi</module> in this regard, except that you can turn off the
-    feature.</p>
+    feature or specify the use of a header other than <code>Location</code>.</p>
 
     <example><title>Example</title>
     <highlight language="config">
     ProxySCGIInternalRedirect Off
+
+# Django and some other frameworks will fully qualify "local URLs"
+# set by the application, so an alternate header must be used.
+&lt;Location /django-app/&gt;
+    ProxySCGIInternalRedirect X-Location
+&lt;/Location&gt;
     </highlight>
     </example>
 </usage>

diff --git a/modules/proxy/mod_proxy_scgi.c b/modules/proxy/mod_proxy_scgi.c
index 7fb2b873a9692ef69376e8b6cba0cbc6f20e151c..4083b90fe1dfcf110f56b4ead7c4cd4753c940d6 100644 (file)
--- a/modules/proxy/mod_proxy_scgi.c
+++ b/modules/proxy/mod_proxy_scgi.c
@@ -64,10 +64,12 @@ typedef struct {
 
 const char *scgi_sendfile_off = "off";
 const char *scgi_sendfile_on = "X-Sendfile";
+const char *scgi_internal_redirect_off = "off";
+const char *scgi_internal_redirect_on = "Location";
 
 typedef struct {
     const char *sendfile;
-    int internal_redirect;
+    const char *internal_redirect;
 } scgi_config;
 
 
@@ -417,11 +419,29 @@ static int pass_response(request_rec *r, proxy_conn_rec *conn)
         }
     }
 
-    if (conf->internal_redirect && r->status == HTTP_OK) {
-        location = apr_table_get(r->headers_out, "Location");
+    if (r->status == HTTP_OK 
+        && (!conf->internal_redirect /* default === On */
+            || conf->internal_redirect != scgi_internal_redirect_off)) {
+        short err = 1;
+        const char *location_header = conf->internal_redirect ? 
+            conf->internal_redirect : scgi_internal_redirect_on;
+
+        location = apr_table_get(r->err_headers_out, location_header);
+        if (!location) {
+            err = 0;
+            location = apr_table_get(r->headers_out, location_header);
+        }
         if (location && *location == '/') {
             scgi_request_config *req_conf = apr_palloc(r->pool,
                                                        sizeof(*req_conf));
+            if (strcasecmp(location_header, "Location")) {
+                if (err) {
+                    apr_table_unset(r->err_headers_out, location_header);
+                }
+                else {
+                    apr_table_unset(r->headers_out, location_header);
+                }
+            }
             req_conf->location = location;
             req_conf->type = scgi_internal_redirect;
             ap_set_module_config(r->request_config, &proxy_scgi_module,
@@ -564,8 +584,8 @@ static void *create_scgi_config(apr_pool_t *p, char *dummy)
 {
     scgi_config *conf=apr_palloc(p, sizeof(*conf));
 
-    conf->sendfile = NULL;
-    conf->internal_redirect = -1;
+    conf->sendfile = NULL; /* === default (off) */
+    conf->internal_redirect = NULL; /* === default (on) */
 
     return conf;
 }
@@ -576,7 +596,7 @@ static void *merge_scgi_config(apr_pool_t *p, void *base_, void *add_)
     scgi_config *base=base_, *add=add_, *conf=apr_palloc(p, sizeof(*conf));
 
     conf->sendfile = add->sendfile ? add->sendfile: base->sendfile;
-    conf->internal_redirect =   (add->internal_redirect != -1)
+    conf->internal_redirect = add->internal_redirect
                               ? add->internal_redirect
                               : base->internal_redirect;
     return conf;
@@ -601,16 +621,33 @@ static const char *scgi_set_send_file(cmd_parms *cmd, void *mconfig,
 }
 
 
+static const char *scgi_set_internal_redirect(cmd_parms *cmd, void *mconfig,
+                                              const char *arg)
+{
+    scgi_config *conf = mconfig;
+
+    if (!strcasecmp(arg, "Off")) {
+        conf->internal_redirect = scgi_internal_redirect_off;
+    }
+    else if (!strcasecmp(arg, "On")) {
+        conf->internal_redirect = scgi_internal_redirect_on;
+    }
+    else {
+        conf->internal_redirect = arg;
+    }
+    return NULL;
+}
+
+
 static const command_rec scgi_cmds[] =
 {
     AP_INIT_TAKE1("ProxySCGISendfile", scgi_set_send_file, NULL,
                   RSRC_CONF|ACCESS_CONF,
-                  "The name of the X-Sendfile peudo response header or "
+                  "The name of the X-Sendfile pseudo response header or "
                   "On or Off"),
-    AP_INIT_FLAG("ProxySCGIInternalRedirect", ap_set_flag_slot,
-                 (void*)APR_OFFSETOF(scgi_config, internal_redirect),
-                 RSRC_CONF|ACCESS_CONF,
-                 "Off if internal redirect responses should not be accepted"),
+    AP_INIT_TAKE1("ProxySCGIInternalRedirect", scgi_set_internal_redirect, NULL,
+                  RSRC_CONF|ACCESS_CONF,
+                  "The name of the pseudo response header or On or Off"),
     {NULL}
 };