Creating a RESTful API resource in CakePHP 4

CakePHP lets you convert a controller into a RESTful API resource. We will use a prefixed (in other words, namespaced) controller to prevent cluttering your main controller for that given resource.

Using $routes->setExtensions(['json']); tells the framework to parse the .json extension in the URL. Otherwise it will think it's a part of the method name.

CakePHP 4

1. Create a prefix in config/routes.php:

   $routes->prefix('Api', function (RouteBuilder $routes) {
       $routes->setExtensions(['json']);
       $routes->fallbacks(DashedRoute::class);
   });

2. Create src/Controller/Api/AppController.php:

   viewBuilder()->setOption('serialize', true);
       }
   
   }

3. Create your resource controller, say src/Controller/Api/PostsController.php:

   set([
               'foo' => 'bar',
           ]);
       }
   
   }

4. Optional: Configure your API scope in config/routes.php:

   $routes->scope('/api', function (RouteBuilder $builder) {
       $builder->setRouteClass(DashedRoute::class);
       $builder->setExtensions(['json']);
       $builder->resources('Events', [
           'prefix' => 'Api',
       ]);
   });

CakePHP 5

1. Create a prefix in config/routes.php:

   $routes->prefix('Api', function (RouteBuilder $routes) {
       $routes->setExtensions(['json']);
       $routes->fallbacks(DashedRoute::class);
   });

2. Create src/Controller/Api/AppController.php:

   addViewClasses([\Cake\View\JsonView::class]);
           $this->viewBuilder()->setOption('serialize', true);
       }
   
   }

3. Create your resource controller, say src/Controller/Api/PostsController.php:

   set([
               'foo' => 'bar',
           ]);
       }
   
   }

Try accessing your resource at example.com/api/posts/hello.json.

If something doesn't work right away, always run bin/cake cache clear_all before you spend hours investigating.