$city = isset($_GET['city']) ? $_GET['city'] : $currentCity ;
    $url = 'http://api.openweathermap.org/data/2.5/forecast?q='.$city.'&appid=a12942698b2839d023a8bf84f4066b06&units=metric';
    $path = './cache/'.md5($url);

      if(file_exists($path) && time() - filemtime($path) < 60)
      {
        $data = file_get_contents($path);
        $data = json_decode($data);
      }
      else{
        $data = file_get_contents($url);
        $data = json_decode($data);
        file_put_contents($path, json_encode($data));
      }