Migrating from FuelPHP to Laravel: problem with one response

Question

i'm migrating an old project from fuel to laravel and i'm having trouble with the response to one of the requests. The issue is, i need the response from laravel to be exactly the same as it was in fuel, because i already have the app in iOS and Android and having the same responses means i only need to change the endpoints. I can't seem to replicate the response here:

• FuelPHP code and response:

      $belongs = Model_Belong::find('all',array(
          'where'=>array(
              array('id_user',$id_user),
          ),
      ));
  
  return $this->createResponse(200, 'List', $belongs);
  *****RESPONSE****
  {
  "code": 200,
  "message": "List",
  "data": {
      "[1][1]": {
          "id_user": 1,
          "id_group": 1
      },
      "[1][2]": {
          "id_user": 1,
          "id_group": 2
      },
      "[1][3]": {
          "id_user": 1,
          "id_group": 3
      }
  }
  }
  

• Laravel code and response:

      $belongs = Belong::where('id_user', $id_user)
                  ->get();
  
  return $this->createResponse(200, 'List', $belongs);
  *****RESPONSE*****
  {
  "code": 200,
  "message": "List",
  "data": [
      {
          "id_user": 1,
          "id_group": 1,
      },
      {
          "id_user": 1,
          "id_group": 2,
      },
      {
          "id_user": 1,
          "id_group": 3,
      }
  ]
  }
  

***edit: createResponse() method

    function createResponse($code, $message, $data = [])
{
    if ($data == null) {
       $data = (object)[];
    }
    return response()->json([
        'code' => $code,
        'message' => $message,
        'data' => $data
    ]);

}

Answer 1

I think a hacky solution can be done by producing own key by sql and retrieve it by using KeyBy() as following:

Belong::select([
        'id_user',
        'id_group', 
        DB::raw("CONCAT('[', id_user, '][', id_group, ']') as mykey")
    ])
    ->where('id_user', $id_user)
    ->get()
    ->keyBy('mykey');