[Summary view] [Print] [Text view]

   1  <?php
   2  
   3  /*
   4   * This file is part of the Symfony package.
   5   *
   6   * (c) Fabien Potencier <fabien@symfony.com>
   7   *
   8   * For the full copyright and license information, please view the LICENSE
   9   * file that was distributed with this source code.
  10   */
  11  
  12  namespace Symfony\Component\DependencyInjection\Compiler;
  13  
  14  use Symfony\Component\DependencyInjection\Exception\ServiceCircularReferenceException;
  15  use Symfony\Component\DependencyInjection\ContainerBuilder;
  16  
  17  /**
  18   * Checks your services for circular references.
  19   *
  20   * References from method calls are ignored since we might be able to resolve
  21   * these references depending on the order in which services are called.
  22   *
  23   * Circular reference from method calls will only be detected at run-time.
  24   *
  25   * @author Johannes M. Schmitt <schmittjoh@gmail.com>
  26   */
  27  class CheckCircularReferencesPass implements CompilerPassInterface
  28  {
  29      private $currentPath;
  30      private $checkedNodes;
  31  
  32      /**
  33       * Checks the ContainerBuilder object for circular references.
  34       *
  35       * @param ContainerBuilder $container The ContainerBuilder instances
  36       */
  37      public function process(ContainerBuilder $container)
  38      {
  39          $graph = $container->getCompiler()->getServiceReferenceGraph();
  40  
  41          $this->checkedNodes = array();
  42          foreach ($graph->getNodes() as $id => $node) {
  43              $this->currentPath = array($id);
  44  
  45              $this->checkOutEdges($node->getOutEdges());
  46          }
  47      }
  48  
  49      /**
  50       * Checks for circular references.
  51       *
  52       * @param ServiceReferenceGraphEdge[] $edges An array of Edges
  53       *
  54       * @throws ServiceCircularReferenceException When a circular reference is found.
  55       */
  56      private function checkOutEdges(array $edges)
  57      {
  58          foreach ($edges as $edge) {
  59              $node = $edge->getDestNode();
  60              $id = $node->getId();
  61  
  62              if (empty($this->checkedNodes[$id])) {
  63                  $searchKey = array_search($id, $this->currentPath);
  64                  $this->currentPath[] = $id;
  65  
  66                  if (false !== $searchKey) {
  67                      throw new ServiceCircularReferenceException($id, array_slice($this->currentPath, $searchKey));
  68                  }
  69  
  70                  $this->checkOutEdges($node->getOutEdges());
  71  
  72                  $this->checkedNodes[$id] = true;
  73                  array_pop($this->currentPath);
  74              }
  75          }
  76      }
  77  }