HttpKernel Component
HttpKernel provides the building blocks to create flexible and fast HTTP-based frameworks.
HttpKernelInterface is the core interface of the Symfony full-stack
framework:
interface HttpKernelInterface
{
/**
* Handles a Request to convert it to a Response.
*
* @param Request $request A Request instance
*
* @return Response A Response instance
*/
function handle(Request $request, $type = self::MASTER_REQUEST, $catch = true);
}It takes a Request as an input and should return a Response as an
output. Using this interface makes your code compatible with all frameworks
using the Symfony components. And this will give you many cool features for
free.
Creating a framework based on the Symfony components is really easy. Here is a very simple, but fully-featured framework based on the Symfony components:
$routes = new RouteCollection();
$routes->add('hello', new Route('/hello', array('_controller' =>
function (Request $request) {
return new Response(sprintf("Hello %s", $request->get('name')));
}
)));
$request = Request::createFromGlobals();
$context = new RequestContext();
$context->fromRequest($request);
$matcher = new UrlMatcher($routes, $context);
$dispatcher = new EventDispatcher();
$dispatcher->addSubscriber(new RouterListener($matcher));
$resolver = new ControllerResolver();
$kernel = new HttpKernel($dispatcher, $resolver);
$kernel->handle($request)->send();This is all you need to create a flexible framework with the Symfony components.
Want to add an HTTP reverse proxy and benefit from HTTP caching and Edge Side Includes?
$kernel = new HttpKernel($dispatcher, $resolver);
$kernel = new HttpCache($kernel, new Store(__DIR__.'/cache'));Want to functional test this small framework?
$client = new Client($kernel);
$crawler = $client->request('GET', '/hello/Fabien');
$this->assertEquals('Fabien', $crawler->filter('p > span')->text());Want nice error pages instead of ugly PHP exceptions?
$dispatcher->addSubscriber(new ExceptionListener(function (Request $request) {
$msg = 'Something went wrong! ('.$request->get('exception')->getMessage().')';
return new Response($msg, 500);
}));And that's why the simple looking HttpKernelInterface is so powerful. It
gives you access to a lot of cool features, ready to be used out of the box,
with no efforts.
Resources
You can run the unit tests with the following command:
$ cd path/to/Symfony/Component/HttpKernel/
$ composer install
$ phpunit