REST Route Ideas

AppointmentController.php

<?php

class AppointmentController extends \BaseController {
  
  public function index($id) 
  {
      if ($id) {
        $appts = $this->appointments->getAllForUser($id);
      } else {
        $appts = $this->appointments->getAll();
      }
      
      return $appts;
  }
}

routes.php

<?php

// Basic CRUD endpoints from this
Route::resource('users', 'UserController');

// Then you have two options for /users/{id}/appointments, this:
Route::get('users/{id}/appointments', 'UserController@appointments');
// Or this:
Route::get('users/{id}/appointments', 'AppointmentController@index');

// The second one might be more desirable, since you already 
// have the assets to get appointments in that controller, and Laravel will
// Reveal that you have an ID being passed to the function