Fixes #2160 #2678 introducing a more flexible simplecache handler (this requires an htaccess update)

git-svn-id: http://code.elgg.org/elgg/trunk@7464 36083f99-b078-4883-b0ff-0f9b5a30f544

1 files changed, 89 insertions, 0 deletions

diff --git a/engine/handlers/cache_handler.php b/engine/handlers/cache_handler.php
new file mode 100644
index 000000000..d08863a00
--- /dev/null
+++ b/engine/handlers/cache_handler.php
@@ -0,0 +1,89 @@
+<?php
+/**
+ * Cache handler.
+ * 
+ * External access to cached CSS and JavaScript views. The cached file URLS
+ * should be of the form: cache/<type>/<view>/<viewtype>/<unique_id> where
+ * type is either css or js, view is the name of the cached view, and
+ * unique_id is an identifier that is updated every time the cache is flushed.
+ * The simplest way to maintain a unique identifier is to use the lastcache
+ * variable in Elgg's config object.
+ *
+ * @see elgg_view_register_simplecache()
+ *
+ * @package Elgg.Core
+ * @subpackage Cache
+ */
+
+// Get dataroot
+require_once(dirname(dirname(__FILE__)) . '/settings.php');
+$mysql_dblink = mysql_connect($CONFIG->dbhost, $CONFIG->dbuser, $CONFIG->dbpass, true);
+if (!$mysql_dblink) {
+	echo 'Cache error: unable to connect to database server';
+	exit;
+}
+
+if (!mysql_select_db($CONFIG->dbname, $mysql_dblink)) {
+	echo 'Cache error: unable to connect to Elgg database';
+	exit;
+}
+
+$query = "select name, value from {$CONFIG->dbprefix}datalists where name = 'dataroot'";
+$result = mysql_query($query, $mysql_dblink);
+if (!$result) {
+	echo 'Cache error: unable to get the data root';
+	exit;
+}
+$row = mysql_fetch_object($result);
+$dataroot = $row->value;
+
+
+
+$dirty_request = $_GET['request'];
+// only alphanumeric characters plus / and . and no '..'
+$filter = array("options" => array("regexp" => "/^(\.?[a-zA-Z0-9\/]+)+$/"));
+$request = filter_var($dirty_request, FILTER_VALIDATE_REGEXP, $filter);
+if (!$request) {
+	echo 'Cache error: bad request';
+	exit;
+}
+$request = explode('/', $request);
+
+
+//cache/<type>/<view>/<viewtype>/
+$type = $request[0];
+$view = $request[1];
+$viewtype = $request[2];
+
+switch ($type) {
+	case 'css':
+		header("Content-type: text/css", true);
+		header('Expires: ' . date('r', time() + 86400000), true);
+		header("Pragma: public", true);
+		header("Cache-Control: public", true);
+
+		$view = "css/$view";
+		break;
+	case 'js':
+		header('Content-type: text/javascript', true);
+		header('Expires: ' . date('r', time() + 864000000), true);
+		header("Pragma: public", true);
+		header("Cache-Control: public", true);
+
+		$view = "js/$view";
+		break;
+}
+
+$filename = $dataroot . 'views_simplecache/' . md5($viewtype . $view);
+
+if (file_exists($filename)) {
+	$contents = file_get_contents($filename);
+} else {
+	// someone trying to access a non-cached file or a race condition with cache flushing
+	mysql_close($mysql_dblink);
+	require_once(dirname(dirname(__FILE__)) . "/start.php");
+	elgg_set_viewtype($viewtype);
+	$contents = elgg_view($view);
+}
+
+echo $contents;