David Buchmann - david@liip.ch

PHP Engineer, Liip AG, Switzerland

We are hiring: https://liip.ch/jobs

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`-- www
    `-- htdocs
        |-- index.htm
        |-- about.htm
        `-- news.htm
            

What about...

• application architecture?
• consistent URL schema?
• SEO?
• generating links?

Front controller

RewriteRule ^(.*)$ app.php [QSA,L]
            

Routing

What PHP code to call for an URL?

switch($path) {
    case '/':
        return $controller->renderHomepage();
    case '/about':
        return $controller->renderAbout();
    default:
        return $controller->render404();
}
            

What about /product/{id} ?

Regular Expressions!

What about flexibility and efficiency?

...

Use an existing library!

The Symfony Routing component

• Transform Request object to hashmap with routing information
• Full stack framework: _controller
• Match on URL, hostname or other headers
• Order of route definition matters: First match wins

The default router

• RouteCollection and ways to define it
• UrlMatcher and UrlGenerator
• Router (all in one)
  • LoaderInterface
  • Matcher and generator
  • Caching functionality

Define routes

• In annotations on the controller
• In configuration files (YAML, XML)
• PHP code calling a configuration API
  
  
• Routing is compiled to PHP code

Caching

• During development: Checks for file changes
• Production: Only on cache:clear

Optimizations

• Compile routes to PHP
• Dump matcher, single class
• Group similar routes
• Prefer strpos, use regex only when needed
• Possesive quantifiers in regex

Optimizations: Group routes

/foo/x/{id}


/foo/y/{id}

/bar/baz
            

/foo
+---/x/
|   `--{id}
`---/y/
    `--{id}
/bar/baz
            

Tweaks in your application

• Most frequently hit routes first
• Order matters: Similar paths consecutive

Providing Context

$context = $this->router->getContext();

$context->setHost('example.com');
$context->setScheme('https');
$context->setBaseUrl('my/path');

$this->router->generate(...);
            

Custom router implementation

• Router used in every single request
• Careful with side effects
• Look at the ChainRouter

Routing in the Symfony Framework

Route sources

• Configuration files
• Load routes in php files for flexibility
• Custom route loaders
• Service as route resource:

                  # app/config/routing.yaml
                  admin_routes:
                      type: service
                      resource: "admin_route_loader:loadRoutes"
              

Custom loader: FOSRestBundle

                # app/config/routing.yml
                product:
                    type: rest
                    resource: AppBundle\Controller\ProductController
            

• Reflection on controller class
• Naming conventions
• Annotations to tweak things
• No need to define routes explicitly

Custom Routers: Multilanguage

• Different URL per language
• Detect locale
• Generate URL in requested locale
• Avoid duplication of configuration

JMSI18nRoutingBundle

• Translate pattern in Symfony translation
• Path prefix for locale or domain per locale

# routing.yml
homepage:
    path:  /welcome
    defaults: { _controller: MyWebsiteBundle:Frontend:index }

# translations/routes.de.yml
homepage: /willkommen

BeSimpleI18nRoutingBundle

• Custom type of route when loading
• Configure path in localized fields

type: be_simple_i18n
...
homepage:
    locales:
        en: /welcome
        de: /willkommen
    defaults: { _controller: MyWebsiteBundle:Frontend:index }

CMF DynamicRouter

• Load candidate routes from database
• Indexed lookup
• Handle huge number of routes with no performance penalty
• No issue with frequently editing routes
• SEO URLs for content pages

CMF ChainRouter

Combine several routers

• Cycle through all routers
• Symfony default and your own or the DynamicRouter

Look Beyond the Horizon

Interact with the route matching

• Routing happens during kernel.request at priority 32
• Add event listeners with a lower priority number
• If you set a Response on the GetResponseEvent, normal routing will not be triggered

FOSHttpCacheBundle hash listener

function onKernelRequest(GetResponseEvent $event) {
  $accept = $event->getRequest()
    ->headers->get('accept');
  if ('user-context-hash' !== $accept) return;
  $hash = $this->hashGenerator->generateHash();
  $response = new Response('', 200, array(
    $this->hashHeader => $hash,
    'Content-Type' => 'user-context-hash',
  ));
  $event->setResponse($response);
}
            

LiipThemeBundle:
Theme specific controllers

            my_route:
                path: /welcome
                defaults:
                    _controller: my_service:fooAction
                    theme_controllers:
                        a: my_other_service:fooAction
                        b: App:Other:foo
            

function onKernelRequest(GetResponseEvent $event) {
    $request = $event->getRequest();
    $theme = $this->activeTheme->getName();
    $controllers = $request->attributes
        ->get('theme_controllers');
    if (isset($controllers[$theme])) {
        $request->attributes->set(
            '_controller',
            $controllers[$theme]
        );
    }
}
            

https://symfony.com/doc/current/components/http_kernel.html

ParamConverter

• Convert string (id, slug, ...) to object
• Based on controller method signature
• ORM and DateTime converter provided
• Annotations to tweak behaviour
• Write your own
• Triggered during the kernel.controller event

Questions / Input / Feedback ?

Twitter: @dbu