code: protected function initialize()
      {
          parent::initialize();
  
          $loader = new ValidatingArrayLoader(new ArrayLoader(null, true), false);
          foreach ($this->config as $package) {
              try {
                  $package = $loader->load($package);
              } catch (\Exception $e) {
                  throw new InvalidRepositoryException('A repository of type "package" contains an invalid package definition: '.$e->getMessage()."\n\nInvalid package definition:\n".json_encode($package));
              }
  
              $this->addPackage($package);
          }
      }
docs: Initializes repository (reads file, or remote address).