Initial work restoring 404 handling in Datasources and catching recur…

…sive 404's. RE: #1539

symphony/lib/core/class.frontend.php

@@ -112,7 +112,7 @@ public function display($page) {
 	 *
 	 * @see core.FrontendPageNotFoundExceptionHandler
 	 */
-	Class FrontendPageNotFoundException extends Exception{
+	Class FrontendPageNotFoundException extends Exception {
 
 		/**
 		 * The constructor for `FrontendPageNotFoundException` sets the default
@@ -121,9 +121,11 @@ public function display($page) {
 		public function __construct() {
 			parent::__construct();
 			$pagename = getCurrentPage();
+
 			if (empty($pagename)) {
 				$this->message = __('The page you requested does not exist.');
-			} else {
+			}
+			else {
 				$this->message = __('The page you requested, %s, does not exist.', array('<code>' . $pagename . '</code>'));
 			}
 			$this->code = E_USER_NOTICE;
@@ -151,8 +153,10 @@ public function __construct() {
 		 */
 		public static function render(Exception $e){
 			$page = PageManager::fetchPageByType('404');
+			$previous_exception = Frontend::instance()->getException();
 
-			if(is_null($page['id'])){
+			// No 404 detected, throw default Symphony error page
+			if(is_null($page['id'])) {
 				parent::render(new SymphonyErrorPage(
 						$e->getMessage(),
 						__('Page Not Found'),
@@ -162,9 +166,22 @@ public static function render(Exception $e){
 					)
 				);
 			}
-			else{
+			// Recursive 404
+			else if (isset($previous_exception)) {
+				parent::render(new SymphonyErrorPage(
+						__('This error occurred whilst attempting to resolve the 404 page for the original request.') . ' ' . $e->getMessage(),
+						__('Page Not Found'),
+						'generic',
+						array(),
+						Page::HTTP_STATUS_NOT_FOUND
+					)
+				);
+			}
+			// Handle 404 page
+			else {
 				$url = '/' . PageManager::resolvePagePath($page['id']) . '/';
 
+				Frontend::instance()->setException($e);
 				$output = Frontend::instance()->display($url);
 				echo $output;
 				exit;

symphony/lib/core/class.symphony.php

@@ -75,6 +75,13 @@
 		 */
 		private static $namespace = false;
 
+		/**
+		 * A previous exception that has been fired. Defaults to null.
+		 * @since Symphony 2.3.2
+		 * @var Exception
+		 */
+		private $exception = null;
+
 		/**
 		 * An instance of the Cookie class
 		 * @var Cookie
@@ -565,6 +572,27 @@ public function throwCustomError($message, $heading='Symphony Fatal Error', $sta
 			throw new SymphonyErrorPage($message, $heading, $template, $additional, $status);
 		}
 
+		/**
+		 * Setter accepts a previous Exception. Useful for determining the context
+		 * of a current exception (ie. detecting recursion).
+		 *
+		 * @since Symphony 2.3.2
+		 * @param Exception $ex
+		 */
+		public function setException(Exception $ex) {
+			$this->exception = $ex;
+		}
+
+		/**
+		 * Accessor for `$this->exception`.
+		 *
+		 * @since Symphony 2.3.2
+		 * @return Exception|null
+		 */
+		public function getException() {
+			return $this->exception;
+		}
+
 		/**
 		 * Given the `$page_id` and a `$column`, this function will return an
 		 * array of the given `$column` for the Page, including all parents.

symphony/lib/toolkit/data-sources/class.datasource.section.php

@@ -13,6 +13,9 @@
 	 * @since Symphony 2.3
 	 * @link http://symphony-cms.com/learn/concepts/view/data-sources/
 	 */
+
+	require_once(TOOLKIT . '/class.entrymanager.php');
+
 	Class SectionDatasource extends Datasource {
 
 		/**
@@ -361,13 +364,10 @@ public function processFilters(&$where, &$joins, &$group) {
 		public function execute(array &$param_pool) {
 			$result = new XMLElement($this->dsParamROOTELEMENT);
 			$this->_param_pool = $param_pool;
-
-			$where = NULL;
-			$joins = NULL;
+			$where = null;
+			$joins = null;
 			$group = false;
 
-			include_once(TOOLKIT . '/class.entrymanager.php');
-
 			if(!$section = SectionManager::fetch((int)$this->getSource())){
 				$about = $this->about();
 				trigger_error(__('The Section, %s, associated with the Data source, %s, could not be found.', array($this->getSource(), '<code>' . $about['name'] . '</code>')), E_USER_ERROR);
@@ -459,7 +459,7 @@ public function execute(array &$param_pool) {
 			));
 
 			if(($entries['total-entries'] <= 0 || $include_pagination_element === true) && (!is_array($entries['records']) || empty($entries['records'])) || $this->dsParamSTARTPAGE == '0'){
-				if($this->dsParamREDIRECTONEMPTY == 'yes'){
+				if($this->dsParamREDIRECTONEMPTY == 'yes') {
 					throw new FrontendPageNotFoundException;
 				}
 				$this->_force_empty_result = false;

symphony/template/blueprints.datasource.tpl

@@ -2,20 +2,20 @@
 
 	require_once(TOOLKIT . '/class.datasource.php');
 
-	Class datasource<!-- CLASS NAME --> extends <!-- CLASS EXTENDS -->{
+	Class datasource<!-- CLASS NAME --> extends <!-- CLASS EXTENDS --> {
 
 		<!-- VAR LIST -->
 
 		<!-- FILTERS -->
 
 		<!-- INCLUDED ELEMENTS -->
 
-		public function __construct($env=NULL, $process_params=true){
+		public function __construct($env=NULL, $process_params=true) {
 			parent::__construct($env, $process_params);
 			$this->_dependencies = array(<!-- DS DEPENDENCY LIST -->);
 		}
 
-		public function about(){
+		public function about() {
 			return array(
 				'name' => '<!-- NAME -->',
 				'author' => array(
@@ -27,12 +27,31 @@
 			);
 		}
 
-		public function getSource(){
+		public function getSource() {
 			return '<!-- SOURCE -->';
 		}
 
-		public function allowEditorToParse(){
+		public function allowEditorToParse() {
 			return true;
 		}
 
+		public function execute($param_pool = null) {
+			try{
+				$result = parent::execute();
+			}
+			catch(FrontendPageNotFoundException $e){
+				// Work around. This ensures the 404 page is displayed and
+				// is not picked up by the default catch() statement below
+				FrontendPageNotFoundExceptionHandler::render($e);
+			}
+			catch(Exception $e){
+				$result->appendChild(new XMLElement('error', $e->getMessage()));
+				return $result;
+			}
+
+			if($this->_force_empty_result) $result = $this->emptyXMLSet();
+
+			return $result;
+		}
+
 	}