RouteReference

Description

Sometimes, when generating links to a resource, you need to modify the default router's behavior.

Use cases can be:

• Language switch links
• Download links
• Pass a Content item instead of a Location (and use its mainLocationId)

Solution

The concept of RouteReference has been introduced, which works in the same way of Symfony's ControllerReference for sub-requests. A RouteReference represents a route (to a location object, a declared route...) with its parameters and can be passed to the Router for link generation.

The advantage of a RouteReference is that its params can be modified later, and then passed to the router (e.g. to generate a link to the same location in several different languages).

Furthermore, the RouteReference generation process can be extended to fit specific needs.

Usage

Twig

Prototype:

• routing_resource can be any valid resource (route name, Location object...). If omitted (null), the current route will be taken into account.
• parameters_hash is a hash with arbitrary key/values. It will be passed to the router in the end.

Minimal usage is pretty straightforward:

Passing parameters and play with the RouteReference:

PHP

You can easily generate links based on a RouteReference from PHP too, with the RouteReferenceGenerator service:

Extending the RouteReference generation process

When generating the route reference, the RouteReferenceGenerator service fires an MVCEvents::ROUTE_REFERENCE_GENERATION (exponential.routing.reference_generation) event. This event can be listened to in order to modify the final route reference (adding/changing parameters, changing the route name...).

All listeners receive a eZ\Publish\Core\MVC\Symfony\Event\RouteReferenceGenerationEvent object, which contains the current request object and the route reference.

Service declaration: