0👍
Ended up to use Laravel collection map feature. Mu route looks now like this
Route::get('/cities/{country_id}', function (Request $request, $country_id) {
$collection=App\City::where('country_id', $country_id)->get();
$cities=$collection->map(function($city){
return ['id' => $city->id, 'name' => $city->name];
})->toArray();
Long live Laracast forums and bashy 🙂
Source:stackexchange.com