<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel;
use Symfony\Component\EventDispatcher\EventDispatcherInterface;
use Symfony\Component\HttpFoundation\Exception\RequestExceptionInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\RequestStack;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\Controller\ArgumentResolver;
use Symfony\Component\HttpKernel\Controller\ArgumentResolverInterface;
use Symfony\Component\HttpKernel\Controller\ControllerResolverInterface;
use Symfony\Component\HttpKernel\Event\FilterControllerArgumentsEvent;
use Symfony\Component\HttpKernel\Event\FilterControllerEvent;
use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
use Symfony\Component\HttpKernel\Event\FinishRequestEvent;
use Symfony\Component\HttpKernel\Event\GetResponseEvent;
use Symfony\Component\HttpKernel\Event\GetResponseForControllerResultEvent;
use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
use Symfony\Component\HttpKernel\Event\PostResponseEvent;
use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
use Symfony\Component\HttpKernel\Exception\ControllerDoesNotReturnResponseException;
use Symfony\Component\HttpKernel\Exception\HttpExceptionInterface;
use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
/**
* HttpKernel notifies events to convert a Request object to a Response one.
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class HttpKernel implements HttpKernelInterface, TerminableInterface {
protected $dispatcher;
protected $resolver;
protected $requestStack;
private $argumentResolver;
public function __construct(EventDispatcherInterface $dispatcher, ControllerResolverInterface $resolver, RequestStack $requestStack = null, ArgumentResolverInterface $argumentResolver = null) {
$this->dispatcher = $dispatcher;
$this->resolver = $resolver;
$this->requestStack = $requestStack ?: new RequestStack();
$this->argumentResolver = $argumentResolver;
if (null === $this->argumentResolver) {
$this->argumentResolver = new ArgumentResolver();
}
}
/**
* {@inheritdoc}
*/
public function handle(Request $request, $type = HttpKernelInterface::MASTER_REQUEST, $catch = true) {
$request->headers->set('X-Php-Ob-Level', ob_get_level());
try {
return $this->handleRaw($request, $type);
} catch (\Exception $e) {
if ($e instanceof RequestExceptionInterface) {
$e = new BadRequestHttpException($e->getMessage(), $e);
}
if (false === $catch) {
$this->finishRequest($request, $type);
throw $e;
}
return $this->handleException($e, $request, $type);
}
}
/**
* {@inheritdoc}
*/
public function terminate(Request $request, Response $response) {
$this->dispatcher->dispatch(KernelEvents::TERMINATE, new PostResponseEvent($this, $request, $response));
}
/**
* @internal
*/
public function terminateWithException(\Exception $exception, Request $request = null) {
if (!$request = $request ?: $this->requestStack->getMasterRequest()) {
throw $exception;
}
$response = $this->handleException($exception, $request, self::MASTER_REQUEST);
$response->sendHeaders();
$response->sendContent();
$this->terminate($request, $response);
}
/**
* Handles a request to convert it to a response.
*
* Exceptions are not caught.
*
* @param Request $request A Request instance
* @param int $type The type of the request (one of HttpKernelInterface::MASTER_REQUEST or HttpKernelInterface::SUB_REQUEST)
*
* @return Response A Response instance
*
* @throws \LogicException If one of the listener does not behave as expected
* @throws NotFoundHttpException When controller cannot be found
*/
private function handleRaw(Request $request, int $type = self::MASTER_REQUEST) {
$this->requestStack->push($request);
// request
$event = new GetResponseEvent($this, $request, $type);
$this->dispatcher->dispatch(KernelEvents::REQUEST, $event);
if ($event->hasResponse()) {
return $this->filterResponse($event->getResponse(), $request, $type);
}
// load controller
if (false === $controller = $this->resolver->getController($request)) {
throw new NotFoundHttpException(sprintf('Unable to find the controller for path "%s". The route is wrongly configured.', $request->getPathInfo()));
}
$event = new FilterControllerEvent($this, $controller, $request, $type);
$this->dispatcher->dispatch(KernelEvents::CONTROLLER, $event);
$controller = $event->getController();
// controller arguments
$arguments = $this->argumentResolver->getArguments($request, $controller);
$event = new FilterControllerArgumentsEvent($this, $controller, $arguments, $request, $type);
$this->dispatcher->dispatch(KernelEvents::CONTROLLER_ARGUMENTS, $event);
$controller = $event->getController();
$arguments = $event->getArguments();
// call controller
$response = $controller(...$arguments);
// view
if (!$response instanceof Response) {
$event = new GetResponseForControllerResultEvent($this, $request, $type, $response);
$this->dispatcher->dispatch(KernelEvents::VIEW, $event);
if ($event->hasResponse()) {
$response = $event->getResponse();
} else {
$msg = sprintf('The controller must return a "Symfony\Component\HttpFoundation\Response" object but it returned %s.', $this->varToString($response));
// the user may have forgotten to return something
if (null === $response) {
$msg .= ' Did you forget to add a return statement somewhere in your controller?';
}
throw new ControllerDoesNotReturnResponseException($msg, $controller, __FILE__, __LINE__ - 17);
}
}
return $this->filterResponse($response, $request, $type);
}
/**
* Filters a response object.
*
* @param Response $response A Response instance
* @param Request $request An error message in case the response is not a Response object
* @param int $type The type of the request (one of HttpKernelInterface::MASTER_REQUEST or HttpKernelInterface::SUB_REQUEST)
*
* @return Response The filtered Response instance
*
* @throws \RuntimeException if the passed object is not a Response instance
*/
private function filterResponse(Response $response, Request $request, int $type) {
$event = new FilterResponseEvent($this, $request, $type, $response);
$this->dispatcher->dispatch(KernelEvents::RESPONSE, $event);
$this->finishRequest($request, $type);
return $event->getResponse();
}
/**
* Publishes the finish request event, then pop the request from the stack.
*
* Note that the order of the operations is important here, otherwise
* operations such as {@link RequestStack::getParentRequest()} can lead to
* weird results.
*/
private function finishRequest(Request $request, int $type) {
$this->dispatcher->dispatch(KernelEvents::FINISH_REQUEST, new FinishRequestEvent($this, $request, $type));
$this->requestStack->pop();
}
/**
* Handles an exception by trying to convert it to a Response.
*
* @param \Exception $e An \Exception instance
* @param Request $request A Request instance
* @param int $type The type of the request (one of HttpKernelInterface::MASTER_REQUEST or HttpKernelInterface::SUB_REQUEST)
*
* @throws \Exception
*/
private function handleException(\Exception $e, Request $request, int $type): Response {
$event = new GetResponseForExceptionEvent($this, $request, $type, $e);
$this->dispatcher->dispatch(KernelEvents::EXCEPTION, $event);
// a listener might have replaced the exception
$e = $event->getException();
if (!$event->hasResponse()) {
$this->finishRequest($request, $type);
throw $e;
}
$response = $event->getResponse();
// the developer asked for a specific status code
if (!$event->isAllowingCustomResponseCode() && !$response->isClientError() && !$response->isServerError() && !$response->isRedirect()) {
// ensure that we actually have an error response
if ($e instanceof HttpExceptionInterface) {
// keep the HTTP status code and headers
$response->setStatusCode($e->getStatusCode());
$response->headers->add($e->getHeaders());
} else {
$response->setStatusCode(500);
}
}
try {
return $this->filterResponse($response, $request, $type);
} catch (\Exception $e) {
return $response;
}
}
/**
* Returns a human-readable string for the specified variable.
*/
private function varToString($var): string {
if (\is_object($var)) {
return sprintf('an object of type %s', \get_class($var));
}
if (\is_array($var)) {
$a = [];
foreach ($var as $k => $v) {
$a[] = sprintf('%s => ...', $k);
}
return sprintf('an array ([%s])', mb_substr(implode(', ', $a), 0, 255));
}
if (\is_resource($var)) {
return sprintf('a resource (%s)', get_resource_type($var));
}
if (null === $var) {
return 'null';
}
if (false === $var) {
return 'a boolean value (false)';
}
if (true === $var) {
return 'a boolean value (true)';
}
if (\is_string($var)) {
return sprintf('a string ("%s%s")', mb_substr($var, 0, 255), mb_strlen($var) > 255 ? '...' : '');
}
if (is_numeric($var)) {
return sprintf('a number (%s)', (string) $var);
}
return (string) $var;
}
}