mod_cache: Make CacheEnable and CacheDisable configurable per

directory in addition to per server, making them work from within
a LocationMatch.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1080834 13f79535-47bb-0310-9956-ffa450edef68

CHANGES

@@ -2,6 +2,10 @@
 
 Changes with Apache 2.3.12
 
+  *) mod_cache: Make CacheEnable and CacheDisable configurable per
+     directory in addition to per server, making them work from within
+     a LocationMatch. [Graham Leggett]
+
   *) worker, event, prefork: Correct several issues when built as
      DSOs; most notably, the scoreboard was reinitialized during graceful
      restart, such that processes of the previous generation were not

docs/manual/mod/mod_cache.xml

@@ -332,17 +332,20 @@
 <name>CacheEnable</name>
 <description>Enable caching of specified URLs using a specified storage
 manager</description>
-<syntax>CacheEnable <var>cache_type</var> <var>url-string</var></syntax>
+<syntax>CacheEnable <var>cache_type</var> [<var>url-string</var>]</syntax>
 <contextlist><context>server config</context><context>virtual host</context>
+<context>directory</context><context>.htaccess</context>
 </contextlist>
 
 <usage>
     <p>The <directive>CacheEnable</directive> directive instructs
     <module>mod_cache</module> to cache urls at or below
     <var>url-string</var>. The cache storage manager is specified with the
-    <var>cache_type</var> argument. If the <directive>CacheEnable</directive>
+    <var>cache_type</var> argument. The <directive>CacheEnable</directive>
-    directive is placed inside a <directive type="section">Location</directive>
+    directive can alternatively be placed inside either
-    directive, the <var>url-string</var> becomes optional.
+    <directive type="section">Location</directive> or
+    <directive type="section">LocationMatch</directive> sections to indicate
+    the content is cacheable.
     <var>cache_type</var> <code>disk</code> instructs
     <module>mod_cache</module> to use the disk based storage manager
     implemented by <module>mod_cache_disk</module>.</p>
@@ -351,13 +354,28 @@ manager</description>
     each possible storage manager will be run until the first one that
     actually processes the request. The order in which the storage managers are
     run is determined by the order of the <directive>CacheEnable</directive>
-    directives in the configuration file.</p>
+    directives in the configuration file. <directive>CacheEnable</directive>
+    directives within <directive type="section">Location</directive> or
+    <directive type="section">LocationMatch</directive> sections are processed
+    before globally defined <directive>CacheEnable</directive> directives.</p>
 
     <p>When acting as a forward proxy server, <var>url-string</var> can
     also be used to specify remote sites and proxy protocols which 
     caching should be enabled for.</p>
- 
+
     <example>
+      # Cache content<br />
+      &lt;Location /foo&gt;<br />
+      <indent>
+        CacheEnable disk<br />
+      </indent>
+      &lt;/Location&gt;<br /><br />
+      # Cache regex<br />
+      &lt;LocationMatch foo$&gt;<br />
+      <indent>
+        CacheEnable disk<br />
+      </indent>
+      &lt;/LocationMatch&gt;<br /><br />
       # Cache proxied url's<br />
       CacheEnable  disk  /<br /><br />
       # Cache FTP-proxied url's<br />
@@ -390,6 +408,7 @@ manager</description>
 <description>Disable caching of specified URLs</description>
 <syntax>CacheDisable <var>url-string</var> | <var>on</var></syntax>
 <contextlist><context>server config</context><context>virtual host</context>
+<context>directory</context><context>.htaccess</context>
 </contextlist>
 
 <usage>
@@ -407,11 +426,13 @@ manager</description>
 
     <example><title>Example</title>
       &lt;Location /foo&gt;<br />
+      <indent>
         CacheDisable on<br />
+      </indent>
       &lt;/Location&gt;<br />
     </example>
 
-    <p> The <code>no-cache</code> environment variable can be set to 
+    <p>The <code>no-cache</code> environment variable can be set to 
     disable caching on a finer grained set of resources in versions
     2.2.12 and later.</p>
 

modules/cache/cache_util.c

@@ -126,51 +126,58 @@ static int uri_meets_conditions(const apr_uri_t *filter, const int pathlen,
     return !strncmp(filter->path, url->path, pathlen);
 }
 
+static cache_provider_list *get_provider(request_rec *r, struct cache_enable *ent,
+        cache_provider_list *providers)
+{
+    /* Fetch from global config and add to the list. */
+    cache_provider *provider;
+    provider = ap_lookup_provider(CACHE_PROVIDER_GROUP, ent->type,
+                                  "0");
+    if (!provider) {
+        /* Log an error! */
+    }
+    else {
+        cache_provider_list *newp;
+        newp = apr_pcalloc(r->pool, sizeof(cache_provider_list));
+        newp->provider_name = ent->type;
+        newp->provider = provider;
+
+        if (!providers) {
+            providers = newp;
+        }
+        else {
+            cache_provider_list *last = providers;
+
+            while (last->next) {
+                if (last->provider == provider) {
+                    return providers;
+                }
+                last = last->next;
+            }
+            if (last->provider == provider) {
+                return providers;
+            }
+            last->next = newp;
+        }
+    }
+
+    return providers;
+}
+
 cache_provider_list *cache_get_providers(request_rec *r,
         cache_server_conf *conf,
         apr_uri_t uri)
 {
+    cache_dir_conf *dconf = dconf = ap_get_module_config(r->per_dir_config, &cache_module);
     cache_provider_list *providers = NULL;
     int i;
 
-    /* loop through all the cacheenable entries */
+    /* per directory cache disable */
-    for (i = 0; i < conf->cacheenable->nelts; i++) {
+    if (dconf->disable) {
-        struct cache_enable *ent =
+        return NULL;
-                                (struct cache_enable *)conf->cacheenable->elts;
-        if (uri_meets_conditions(&ent[i].url, ent[i].pathlen, &uri)) {
-            /* Fetch from global config and add to the list. */
-            cache_provider *provider;
-            provider = ap_lookup_provider(CACHE_PROVIDER_GROUP, ent[i].type,
-                                          "0");
-            if (!provider) {
-                /* Log an error! */
-            }
-            else {
-                cache_provider_list *newp;
-                newp = apr_pcalloc(r->pool, sizeof(cache_provider_list));
-                newp->provider_name = ent[i].type;
-                newp->provider = provider;
-
-                if (!providers) {
-                    providers = newp;
-                }
-                else {
-                    cache_provider_list *last = providers;
-
-                    while (last->next) {
-                        last = last->next;
-                    }
-                    last->next = newp;
-                }
-            }
-        }
     }
 
-    /* then loop through all the cachedisable entries
+    /* global cache disable */
-     * Looking for urls that contain the full cachedisable url and possibly
-     * more.
-     * This means we are disabling cachedisable url and below...
-     */
     for (i = 0; i < conf->cachedisable->nelts; i++) {
         struct cache_disable *ent =
                                (struct cache_disable *)conf->cachedisable->elts;
@@ -180,6 +187,22 @@ cache_provider_list *cache_get_providers(request_rec *r,
         }
     }
 
+    /* loop through all the per directory cacheenable entries */
+    for (i = 0; i < dconf->cacheenable->nelts; i++) {
+        struct cache_enable *ent =
+                                (struct cache_enable *)dconf->cacheenable->elts;
+        providers = get_provider(r, &ent[i], providers);
+    }
+
+    /* loop through all the global cacheenable entries */
+    for (i = 0; i < conf->cacheenable->nelts; i++) {
+        struct cache_enable *ent =
+                                (struct cache_enable *)conf->cacheenable->elts;
+        if (uri_meets_conditions(&ent[i].url, ent[i].pathlen, &uri)) {
+            providers = get_provider(r, &ent[i], providers);
+        }
+    }
+
     return providers;
 }
 

modules/cache/cache_util.h

@@ -164,6 +164,10 @@ typedef struct {
     apr_time_t defex;
     /* factor for estimating expires date */
     double factor;
+    /* cache enabled for this location */
+    apr_array_header_t *cacheenable;
+    /* cache disabled for this location */
+    int disable:1;
     /* set X-Cache headers */
     int x_cache:1;
     int x_cache_detail:1;
@@ -188,6 +192,8 @@ typedef struct {
     int store_expired_set:1;
     int store_private_set:1;
     int store_nostore_set:1;
+    int enable_set:1;
+    int disable_set:1;
 } cache_dir_conf;
 
 /* A linked-list of authn providers. */

modules/cache/mod_cache.c

@@ -1720,6 +1720,9 @@ static void *create_dir_config(apr_pool_t *p, char *dummy)
 
     dconf->stale_on_error = DEFAULT_CACHE_STALE_ON_ERROR;
 
+    /* array of providers for this URL space */
+    dconf->cacheenable = apr_array_make(p, 10, sizeof(struct cache_enable));
+
     return dconf;
 }
 
@@ -1764,6 +1767,12 @@ static void *merge_dir_config(apr_pool_t *p, void *basev, void *addv) {
     new->stale_on_error_set = add->stale_on_error_set
             || base->stale_on_error_set;
 
+    new->cacheenable = add->enable_set ? apr_array_append(p, base->cacheenable,
+            add->cacheenable) : base->cacheenable;
+    new->enable_set = add->enable_set || base->enable_set;
+    new->disable = (add->disable_set == 0) ? base->disable : add->disable;
+    new->disable_set = add->disable_set || base->disable_set;
+
     return new;
 }
 
@@ -1993,6 +2002,7 @@ static const char *add_cache_enable(cmd_parms *parms, void *dummy,
                                     const char *type,
                                     const char *url)
 {
+    cache_dir_conf *dconf = (cache_dir_conf *)dummy;
     cache_server_conf *conf;
     struct cache_enable *new;
 
@@ -2023,7 +2033,15 @@ static const char *add_cache_enable(cmd_parms *parms, void *dummy,
     conf =
         (cache_server_conf *)ap_get_module_config(parms->server->module_config,
                                                   &cache_module);
-    new = apr_array_push(conf->cacheenable);
+
+    if (parms->path) {
+        new = apr_array_push(dconf->cacheenable);
+        dconf->enable_set = 1;
+    }
+    else {
+        new = apr_array_push(conf->cacheenable);
+    }
+
     new->type = type;
     if (apr_uri_parse(parms->pool, url, &(new->url))) {
         return NULL;
@@ -2040,6 +2058,7 @@ static const char *add_cache_enable(cmd_parms *parms, void *dummy,
 static const char *add_cache_disable(cmd_parms *parms, void *dummy,
                                      const char *url)
 {
+    cache_dir_conf *dconf = (cache_dir_conf *)dummy;
     cache_server_conf *conf;
     struct cache_disable *new;
 
@@ -2065,6 +2084,13 @@ static const char *add_cache_disable(cmd_parms *parms, void *dummy,
     conf =
         (cache_server_conf *)ap_get_module_config(parms->server->module_config,
                                                   &cache_module);
+
+    if (parms->path) {
+        dconf->disable = 1;
+        dconf->disable_set = 1;
+        return NULL;
+    }
+
     new = apr_array_push(conf->cachedisable);
     if (apr_uri_parse(parms->pool, url, &(new->url))) {
         return NULL;