Add (rudimentary) page exclusion support for the "System - Page Cache…

…" plugin

administrator/language/en-GB/en-GB.plg_system_cache.ini

@@ -5,6 +5,8 @@
 
 PLG_CACHE_FIELD_BROWSERCACHE_DESC="If yes, use mechanism for storing page cache in the browser."
 PLG_CACHE_FIELD_BROWSERCACHE_LABEL="Use Browser Caching"
+PLG_CACHE_FIELD_EXCLUDE_DESC="Specify which pages you wish to exclude from caching, each on a separate line. Regular expressions are supported."
+PLG_CACHE_FIELD_EXCLUDE_LABEL="Exclude Pages"
 PLG_CACHE_FIELD_LIFETIME_DESC="Page cache lifetime in minutes."
 PLG_CACHE_FIELD_LIFETIME_LABEL="Cache Lifetime"
 PLG_CACHE_XML_DESCRIPTION="Provides page caching."

plugins/system/cache/cache.php

@@ -113,10 +113,37 @@ public function onAfterRender()
 
 		$user = JFactory::getUser();
 
-		if ($user->get('guest'))
+		if ($user->get('guest') && !$this->isExcluded())
 		{
 			// We need to check again here, because auto-login plugins have not been fired before the first aid check.
 			$this->_cache->store(null, $this->_cache_key);
 		}
 	}
+
+	protected function isExcluded() {
+		if ($exclusions = $this->params->get('exclude', '')) {
+			// Normalize line endings
+			$exclusions = str_replace(array("\r\n", "\r"), "\n", $exclusions);
+
+			// Split them
+			$exclusions = explode("\n", $exclusions);
+
+			// Get current path to match against
+			$path = JUri::getInstance()->toString(array('path', 'query', 'fragment'));
+
+			// Loop through each pattern
+			if ($exclusions) {
+				foreach ($exclusions as $exclusion) {
+					// Make sure the exclusion has some content
+					if (strlen($exclusion)) {
+						if (preg_match('/'.$exclusion.'/is', $path, $match)) {
+							return true;
+						}
+					}
+				}
+			}
+		}
+
+		return false;
+	}
 }

plugins/system/cache/cache.xml

@@ -28,6 +28,12 @@
 				<option value="1">JYES</option>
 				<option value="0">JNO</option>
 			</field>
+			<field name="exclude" type="textarea"
+				filter="raw"
+				default=""
+				description="PLG_CACHE_FIELD_EXCLUDE_DESC"
+				label="PLG_CACHE_FIELD_EXCLUDE_LABEL"
+			/>
 		</fieldset>
 	</fields>
 	</config>