Dingo api not registering routes

Hi i'm using Dingo Api dev-master b36db17 (1.0.*@dev) with Laravel 5.2.11

When i try to acces my api routes i get an error :

"The version given was unknown or has no registered routes." (status:400)

here is my api route:

$api = app('Dingo\Api\Routing\Router');

$api->version('v1', ['version' => 'v1', 'prefix' => 'api'], function ($api) {

  Route::group(['prefix' => 'api', 'version' => 'v1'], function () {
    //# Version 1 routes here
    Route::post('login', [  
      'uses'      => 'App\Api\V1\Http\Controllers\AuthenticateController@authenticate',
      'as'        => 'api.login'
      ]);
  });
});

the command php artisan api:routes shows nothing

I need some help please

via Chebli Mohamed