Dynamic Route loading in a non standard Symfony structure
2024-08-16
When you divert from Symfony’s standard structure there are some things that do not work out of the box anymore. One of it is routing.
Default Symfony
If you start a fresh Symfony project you will be presented with the following stricture:
app/src
├─ Controller
├─ Entity
├─ Repository
└─ Kernel.php
The routing config looks like this:
# app/config/routes.yaml
controllers:
resource:
path: ../src/Controller/
namespace: App\Controller
type: attribute
So the Controller directory is the place all controllers go you might think first. But When the project gets bigger a different structure might make more sense.
The DDD/Clean Architecture approach
If we use a DDD/Clean Architecture approach the structure might look like this:
app/src
├─ Blog
│ ├─ Application
│ │ └─ CreateArticleController.php
│ ├─ Domain
│ │ └─ Article.php
│ └─ Infrastructure
├─ Registration
│ ├─ Application
│ │ ├─ CreateAccountController.php
│ │ ├─ CreateAccountRequest.php
│ │ └─ CreateAccountResponse.php
│ ├─ Domain
│ │ └─ Account.php
│ └─ Infrastructure
└─ Kernel.php
But now every Controller needs to be added to the routing config since the loading expects all controllers in one place.
# app/config/routes.yaml
app_registration_createaccount:
# loads routes from the PHP attributes of the given class
resource: App\Registration\CreateAccountController
type: attribute
app_blog_createarticle:
# loads routes from the PHP attributes of the given class
resource: App\Blog\CreateArticleController
type: attribute
This is not the comfortable way, since we were starting to embrace the Route attribute because it means we do not need to add each route to the routing config in a growing file and developers must not forget to add or update each route which might get annoying during refactoring.
Loading Routes dynamic
In Symfony there is a simple way we can solve this: We can create our own loader with a custom service.
The implementation
When the main loader parses this, it tries all registered delegate loaders.
If you’re using autoconfigure, your class should implement the RouteLoaderInterface interface to be tagged automatically.
If your service is invokable, you don’t need to specify the method to use.
Your service doesn’t have to extend or implement any special class, but the called method must return a RouteCollection object.
All good points
- We create an invokable service class
- Implement the
RouteLoaderInterface - Let it return a
RouteCollection
app/src
├─ Blog
│ └─ Application
│ └─ CreateArticleController.php
├─ Registration
│ └─ Application
│ └─ CreateAccountController.php
├─ Shared
│ └─ Application
│ └─ Routing
│ └─ RouteLoader.php <=== here
└─ Kernel.php
The Loader class:
<?php
declare(strict_types=1);
namespace App\Shared\Application\Routing;
use ReflectionClass;
use Symfony\Bundle\FrameworkBundle\Routing\RouteLoaderInterface;
use Symfony\Component\Finder\Finder;
use Symfony\Component\Routing\Attribute\Route as RouteAttribute;
use Symfony\Component\Routing\Route;
use Symfony\Component\Routing\RouteCollection;
class RouteLoader implements RouteLoaderInterface
{
private bool $isLoaded = false;
public function __construct(private readonly string $routeLoaderBaseDirectory)
{
}
public function __invoke(mixed $resource, string $type = null): RouteCollection
{
if ($this->isLoaded) {
throw new \RuntimeException('Do not add this loader twice.');
}
$routeCollection = new RouteCollection();
$finder = self::fromDirectories(
$this->routeLoaderBaseDirectory,
$this->routeLoaderBaseDirectory . '/*/**',
);
foreach ($finder as $file) {
$className = $this->getClassNameFromFile($file->getRealPath());
$namespace = $this->getClassNamespaceFromFile($file->getRealPath());
if (!$className || !$namespace) {
continue;
}
$fullQualifiedClassName = $namespace . '\\' . $className;
// Use reflection to check for Symfony Route attributes
$reflectionClass = new ReflectionClass($fullQualifiedClassName);
$attributes = $this->getRouteAttributes($reflectionClass);
// Handle class-level attributes for invokable controller classes
if ($reflectionClass->hasMethod('__invoke')) {
foreach ($attributes as $routeAttribute) {
$route = $this->createRouteFromAttribute($routeAttribute);
$routeName = $routeAttribute->getName() ?? $this->generateRouteName($fullQualifiedClassName, '__invoke');
$routeCollection->add($routeName, $route);
}
continue; // there should only be a class declaration when invokable
}
// Handle method-level attributes
foreach ($reflectionClass->getMethods() as $method) {
foreach ($attributes as $routeAttribute) {
$route = $this->createRouteFromAttribute($routeAttribute);
$routeName = $routeAttribute->getName() ?? $this->generateRouteName($fullQualifiedClassName, $method->getName());
$routeCollection->add($routeName, $route);
}
}
}
$this->isLoaded = true;
return $routeCollection;
}
// ...
}
See full gist.github.com/dazz of RouteLoader.php
Add the class in the routing config:
# app/config/routing.yaml
controllers:
resource: App\Shared\Application\Routing\RouteLoader
type: service
One thing still left to do is make the path with the $routeLoaderBaseDirectory in the service configuration autowirable.
# app/config/services.yaml
parameters:
services:
_defaults:
autowire: true
autoconfigure: true
bind:
string $routeLoaderBaseDirectory: '%kernel.project_dir%/src'
Controller
namespace App\Registration\Application;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpKernel\Attribute\AsController;
use Symfony\Component\Routing\Attribute\Route;
#[AsController] # to make it autowirable
#[Route(
path: '/registration/createaccount',
name: 'app_registration_createaccount',
methods: [Request::METHOD_POST]
)]
final readonly class CreateAccountController
{
public function __invoke(CreateAccountRequest $request): CreateAccountResponse
{
// create account logic
return new CreateAccountResponse();
}
}
bin/console debug:router
> bin/console debug:router
-------------------------------- -------- -------- ------ -----------------------------
Name Method Scheme Host Path
-------------------------------- -------- -------- ------ -----------------------------
app_blog_createarticle POST ANY ANY /blog/article
app_registration_createaccount POST ANY ANY /registration/account
-------------------------------- -------- -------- ------ -----------------------------
