Editing Symfony Routing Basics (section)

== Defining a route ==

Defining a route using annotations in a controller class:<ref>[http://symfony.com/doc/current/book/routing.html#basic-route-configuration Basic Route Configuration], Symfony routing documentation</ref>

<syntaxhighlight lang="php" highlight="5,10">
// src/AppBundle/Controller/BlogController.php
namespace AppBundle\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;

class BlogController extends Controller
{
    /**
     * @Route("/blog/{slug}")
     */
    public function showAction($slug)
    {
        // ...
    }
}
</syntaxhighlight>

This basically creates a new page on the site.

Routes can alternatively be defined using Yaml, XML, or PHP, e.g.:

<syntaxhighlight lang="yaml">
# app/config/config.yml
framework:
    # ...
    router: { resource: "%kernel.root_dir%/config/routing.yml" }
</syntaxhighlight>

=== Wildcards in routes ===

Wildcards are defined with curly braces, e.g. `{slug}` below:<ref>[http://symfony.com/doc/current/book/routing.html#routing-with-placeholders Routing with Placeholders], Symfony routing documentation</ref>

<syntaxhighlight lang="php">
    /**
     * @Route("/blog/{slug}")
     */
    public function showAction($slug)
    {
        // ...
    }
</syntaxhighlight>

This route will match `/blog/*`. Any value placed after `/blog/` will be passed to the method as the value of the `$slug` variable. E.g. a request for `/blog/hello-world` will cause value of `$slug` to be `"hello-world"`.

Note that placeholders are required. In the example above, the URL `/blog` would require its own separate route.

=== Default wildcard values ===

In effect, the `defaults` attribute of `@Route` makes wildcard values optional in URLs:<ref>[http://symfony.com/doc/current/book/routing.html#required-and-optional-placeholders Required and Optional Placeholders], Symfony routing documenation</ref>

<syntaxhighlight lang="php">
    /**
     * @Route("/blog/{page}", defaults={"page"=1})
     */
    public function showAction($page)
    {
        // ...
    }
</syntaxhighlight>

If a page value is not supplied in the URL, `$page` will have a default value of `1`.

=== Restricting wildcard values ===

The `requirements` attribute of the `@Route` annotation enforces formatting of wildcard values with regular expressions.<ref>[http://symfony.com/doc/current/book/routing.html#adding-requirements Adding Requirements], Symfony routing documentation]</ref>

<syntaxhighlight lang="php">
    /**
     * @Route("/blog/{page}", defaults={"page"=1}, requirements={"page"="\d+"})
     */
    public function showAction($page)
    {
        // ...
    }
</syntaxhighlight>

Now only integer values will match the route. A separate route could be created for string values.

=== HTTP method requirements ===

Method requirements are set with the `@Method` annotation: `@Method("GET")`, `@Method("POST")`, etc.<ref>[http://symfony.com/doc/current/book/routing.html#adding-http-method-requirements Adding HTTP Method Requirements], Symfony routing documentation</ref>