ControllerResolver.php

<?php

namespace Drupal\Core\Controller;

use Drupal\Core\DependencyInjection\ClassResolverInterface;
use Symfony\Bridge\PsrHttpMessage\HttpMessageFactoryInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpKernel\Controller\ControllerResolver as BaseControllerResolver;

/**
 * ControllerResolver to enhance controllers beyond Symfony's basic handling.
 *
 * It adds two behaviors:
 *
 *  - When creating a new object-based controller that implements
 *    ContainerAwareInterface, inject the container into it. While not always
 *    necessary, that allows a controller to vary the services it needs at
 *    runtime.
 *
 *  - By default, a controller name follows the class::method notation. This
 *    class adds the possibility to use a service from the container as a
 *    controller by using a service:method notation (Symfony uses the same
 *    convention).
 */
class ControllerResolver extends BaseControllerResolver implements ControllerResolverInterface {
    
    /**
     * The class resolver.
     *
     * @var \Drupal\Core\DependencyInjection\ClassResolverInterface
     */
    protected $classResolver;
    
    /**
     * The PSR-7 converter.
     *
     * @var \Symfony\Bridge\PsrHttpMessage\HttpMessageFactoryInterface
     */
    protected $httpMessageFactory;
    
    /**
     * Constructs a new ControllerResolver.
     *
     * @param \Symfony\Bridge\PsrHttpMessage\HttpMessageFactoryInterface $http_message_factory
     *   The PSR-7 converter.
     * @param \Drupal\Core\DependencyInjection\ClassResolverInterface $class_resolver
     *   The class resolver.
     */
    public function __construct(HttpMessageFactoryInterface $http_message_factory, ClassResolverInterface $class_resolver) {
        $this->httpMessageFactory = $http_message_factory;
        $this->classResolver = $class_resolver;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getControllerFromDefinition($controller, $path = '') {
        if (is_array($controller) || is_object($controller) && method_exists($controller, '__invoke')) {
            return $controller;
        }
        if (strpos($controller, ':') === FALSE) {
            if (function_exists($controller)) {
                return $controller;
            }
            return $this->classResolver
                ->getInstanceFromDefinition($controller);
        }
        $callable = $this->createController($controller);
        if (!is_callable($callable)) {
            throw new \InvalidArgumentException(sprintf('The controller for URI "%s" is not callable.', $path));
        }
        return $callable;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getController(Request $request) {
        if (!($controller = $request->attributes
            ->get('_controller'))) {
            return FALSE;
        }
        return $this->getControllerFromDefinition($controller, $request->getPathInfo());
    }
    
    /**
     * Returns a callable for the given controller.
     *
     * @param string $controller
     *   A Controller string.
     *
     * @return mixed
     *   A PHP callable.
     *
     * @throws \LogicException
     *   If the controller cannot be parsed.
     *
     * @throws \InvalidArgumentException
     *   If the controller class does not exist.
     */
    protected function createController($controller) {
        // Controller in the service:method notation.
        $count = substr_count($controller, ':');
        if ($count == 1) {
            [
                $class_or_service,
                $method,
            ] = explode(':', $controller, 2);
        }
        elseif (strpos($controller, '::') !== FALSE) {
            [
                $class_or_service,
                $method,
            ] = explode('::', $controller, 2);
        }
        else {
            throw new \LogicException(sprintf('Unable to parse the controller name "%s".', $controller));
        }
        $controller = $this->classResolver
            ->getInstanceFromDefinition($class_or_service);
        return [
            $controller,
            $method,
        ];
    }

}