public function index(Request $request)
 {
     $limit = $request->input('limit') ? $request->input('limit') : 10;
     $page = $request->input('page') ? $request->input('page') : 1;
     $offset = ($page - 1) * $limit;
     $total = Campaign::count();
     $dataCampaigns = Campaign::take($limit)->offset($offset)->get();
     $data = ['meta' => ['page' => (int) $page, 'current_total' => count($dataCampaigns), 'total' => $total], 'campaigns' => $dataCampaigns];
     return $data;
 }