Add a RelationUrlGenerator, with a nice Controller trait :)

Controller/HateoasTrait.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace FSC\HateoasBundle\Controller;
+
+trait HateoasTrait
+{
+    protected function generateRelationUrl($object, $rel)
+    {
+        return $this->container->get('fsc_hateoas.routing.relation_url_generator')->generateUrl($object, $rel);
+    }
+
+    protected function generateSelfUrl($object)
+    {
+        return $this->generateRelationUrl($object, 'self');
+    }
+}

Metadata/ClassMetadata.php

@@ -11,16 +11,34 @@ class ClassMetadata extends MergeableClassMetadata implements ClassMetadataInter
      */
     protected $relations = array();
 
+    /**
+     * {@inheritdoc}
+     */
     public function getRelations()
     {
         return $this->relations;
     }
 
+    /**
+     * {@inheritdoc}
+     */
     public function addRelation(RelationMetadataInterface $relation)
     {
         $this->relations[] = $relation;
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function getRelation($rel)
+    {
+        foreach ($this->relations as $relationMetadata) {
+            if ($relationMetadata->getRel() === $rel) {
+                return $relationMetadata;
+            }
+        }
+    }
+
     public function serialize()
     {
         return serialize(array(

Metadata/ClassMetadataInterface.php

@@ -8,4 +8,11 @@ interface ClassMetadataInterface
      * @return array<RelationMetadataInterface>
      */
     public function getRelations();
+
+    /**
+     * @param string $rel
+     *
+     * @return RelationMetadataInterface
+     */
+    public function getRelation($rel);
 }

Metadata/MetadataFactoryInterface.php

@@ -6,6 +6,16 @@
 
 interface MetadataFactoryInterface
 {
+    /**
+     * @param object $object
+     *
+     * @return ClassMetadataInterface
+     */
     public function getMetadata($object);
+
+    /**
+     * @param object $object
+     * @param array $relations
+     */
     public function addObjectRelations($object, array $relations);
 }

README.md

@@ -543,3 +543,36 @@ class UserController extends Controller
     </select>
 </form>
 ```
+
+## RelationUrlGenerator
+
+You can leverage the fact that the hateoas bundle knows how to create url to an object's relation. This is usefull if you
+want generate the self url to an object:
+
+```php
+$user = ...
+$userUrl = $container->get('fsc_hateoas.routing.relation_url_generator')->generateUrl($user, 'self')
+```
+
+You can even use the controller trait:
+
+```php
+<?php
+
+use FSC\HateoasBundle\Controller\HateoasTrait;
+
+class UserController extends Controller
+{
+    public function createUserAction(Request $request)
+    {
+        $user = new User();
+
+        ... // you own stuff
+
+        return Response('', 201, array(
+            'Location' => $this->generateSelfUrl($user),
+        ));
+    }
+}
+
+```

Resources/config/services.yml

@@ -12,6 +12,7 @@ parameters:
     fsc_hateoas.serializer.handler.form.class: FSC\HateoasBundle\Serializer\Handler\FormHandler
     fsc_hateoas.factory.identity.class: FSC\HateoasBundle\Factory\IdentityFactory
     fsc_hateoas.routing.generator.class: FSC\HateoasBundle\Routing\UrlGenerator
+    fsc_hateoas.routing.relation_url_generator.class: FSC\HateoasBundle\Routing\RelationUrlGenerator
 
     fsc_hateoas.json.links_key: ~
     fsc_hateoas.json.relations_key: ~
@@ -105,3 +106,10 @@ services:
         class: %fsc_hateoas.routing.generator.class%
         arguments:
             - @router
+
+    fsc_hateoas.routing.relation_url_generator:
+        class: %fsc_hateoas.routing.relation_url_generator.class%
+        arguments:
+            - @fsc_hateoas.routing.generator
+            - @fsc_hateoas.metadata.factory
+            - @fsc_hateoas.factory.parameters

Routing/RelationUrlGenerator.php

@@ -0,0 +1,36 @@
+<?php
+
+namespace FSC\HateoasBundle\Routing;
+
+use FSC\HateoasBundle\Metadata\MetadataFactoryInterface;
+use FSC\HateoasBundle\Factory\ParametersFactoryInterface;
+
+class RelationUrlGenerator
+{
+    protected $urlGenerator;
+    protected $metadataFactory;
+    protected $parametersFactory;
+
+    public function __construct(UrlGenerator $urlGenerator, MetadataFactoryInterface $metadataFactory,
+        ParametersFactoryInterface $parametersFactory)
+    {
+        $this->urlGenerator = $urlGenerator;
+        $this->metadataFactory = $metadataFactory;
+        $this->parametersFactory = $parametersFactory;
+    }
+
+    public function generateUrl($object, $rel)
+    {
+        $metadata = $this->metadataFactory->getMetadata($object);
+        $relationMetadata = $metadata->getRelation($rel);
+
+        if (null === $relationMetadata) {
+            throw new \RuntimeException(sprintf('Relation "%s" doesn\'t exist.', $rel));
+        }
+
+        return $this->urlGenerator->generate(
+            $relationMetadata->getRoute(),
+            $this->parametersFactory->createParameters($object, $relationMetadata->getParams())
+        );
+    }
+}

Tests/Functional/ControllerTest.php

@@ -28,6 +28,16 @@ public function testGetPostXml()
         , $response->getContent());
     }
 
+    public function testPutPostXml()
+    {
+        $client = $this->createClient();
+        $client->request('PUT', '/api/posts/2');
+
+        $response = $client->getResponse(); /**  */
+
+        $this->assertEquals('http://localhost/api/posts/2', $response->headers->get('Location'));
+    }
+
     public function testGetUserPostsXml()
     {
         $client = $this->createClient();

Tests/Functional/TestBundle/Controller/PostController.php

@@ -46,4 +46,13 @@ public function getCreateFormatPostFormAction(Request $request)
 
         return $this->getCreatePostFormAction($request);
     }
+
+    public function putPostAction($id)
+    {
+        $post = $this->get('test.provider.post')->getPost($id);
+
+        return new Response('', 201, array(
+            'Location' => $this->get('fsc_hateoas.routing.relation_url_generator')->generateUrl($post, 'self'),
+        ));
+    }
 }

Tests/Functional/config/routing.yml

@@ -40,6 +40,13 @@ api_post_get:
     pattern: /api/posts/{id}
     defaults:
         _controller: TestBundle:Post:getPost
+    requirements: { _method: GET }
+
+api_post_put:
+    pattern: /api/posts/{id}
+    defaults:
+        _controller: TestBundle:Post:putPost
+    requirements: { _method: PUT }
 
 api_user_posts_list:
     pattern: /api/users/{id}/posts