caching: Conf updates wrt "location" option.

Uses DownstreamCachePurgeLocationPrefix to avoid loopback through pagespeed server for purge requests.

test/nginx_system_test.sh

@@ -252,8 +252,6 @@ function run_post_cache_flush() {
 
 # Tests related to rewritten response (downstream) caching.
 CACHABLE_HTML_LOC="${SECONDARY_HOSTNAME}/mod_pagespeed_test/cachable_rewritten_html"
-PS_HANDLED_HTML="Passing on content handling.*8050/mod_pagespeed_test/cachable"
-PS_HANDLED_HTML=$PS_HANDLED_HTML"_rewritten_html/downstream_caching.html"
 TMP_LOG_LINE="proxy_cache.example.com GET /purge/mod_pagespeed_test/cachable_rewritten_"
 PURGE_REQUEST_IN_ACCESS_LOG=$TMP_LOG_LINE"html/downstream_caching.html.*(200)"
 
@@ -269,7 +267,6 @@ OUT=$($WGET_DUMP $WGET_ARGS $CACHABLE_HTML_LOC/downstream_caching.html)
 check_not_from "$OUT" egrep -q "pagespeed.ic"
 check_from "$OUT" egrep -q "X-Cache: MISS"
 fetch_until $STATISTICS_URL 'grep -c downstream_cache_purges:\s*1' 1
-check [ $(grep -ce "$PS_HANDLED_HTML" $ERROR_LOG) = 1 ];
 check [ $(grep -ce "$PURGE_REQUEST_IN_ACCESS_LOG" $ACCESS_LOG) = 1 ];
 
 # The 2nd request results in a cache miss (because of the previous purge),
@@ -281,7 +278,6 @@ check_from "$OUT" egrep -q "pagespeed.ic"
 check_from "$OUT" egrep -q "X-Cache: MISS"
 CURRENT_STATS=$($WGET_DUMP $STATISTICS_URL)
 check_from "$CURRENT_STATS" egrep -q "downstream_cache_purges:\s*1"
-check [ $(grep -ce "$PS_HANDLED_HTML" $ERROR_LOG) = 2 ];
 check [ $(grep -ce "$PURGE_REQUEST_IN_ACCESS_LOG" $ACCESS_LOG) = 1 ];
 
 # The 3rd request results in a cache hit (because the previous response is
@@ -292,7 +288,6 @@ OUT=$($WGET_DUMP $WGET_ARGS $CACHABLE_HTML_LOC/downstream_caching.html)
 check_from "$OUT" egrep -q "pagespeed.ic"
 check_from "$OUT" egrep -q "X-Cache: HIT"
 fetch_until $STATISTICS_URL 'grep -c downstream_cache_purges:\s*1' 1
-check [ $(grep -ce "$PS_HANDLED_HTML" $ERROR_LOG) = 2 ];
 check [ $(grep -ce "$PURGE_REQUEST_IN_ACCESS_LOG" $ACCESS_LOG) = 1 ];
 
 start_test Check for correct default X-Page-Speed header format.

test/pagespeed_test.conf.template

@@ -116,6 +116,7 @@ http {
 
     location /mod_pagespeed_test/cachable_rewritten_html/ {
       proxy_pass http://localhost:@@PRIMARY_PORT@@;
+      proxy_set_header Host $host;
       proxy_cache_valid 200 30s;
       proxy_cache htmlcache;
       proxy_ignore_headers Cache-Control;
@@ -511,20 +512,12 @@ http {
       add_header "" "";
     }
 
-    location ~ /purge(/.*) {
-      # Purge requests have to be proxied to the caching layer server:port
-      # since that is the only one that can service it.
-      allow all;
-      proxy_pass http://localhost:@@SECONDARY_PORT@@;
-      proxy_set_header Host proxy_cache.example.com;
-    }
-
     location /mod_pagespeed_test/cachable_rewritten_html/ {
       # This location has the html files that will be configured to be stored
       # in the proxy_cache layer.
       pagespeed DownstreamCacheLifetimeMs 100;
       pagespeed DownstreamCachePurgeMethod "GET";
-      pagespeed DownstreamCachePurgePathPrefix "/purge";
+      pagespeed DownstreamCachePurgeLocationPrefix "http://localhost:8051/purge";
       # We use a very small deadline here to force the rewriting to not complete
       # in the very first attempt.
       pagespeed RewriteDeadlinePerFlushMs 1;