/**
  * methodName
  *
  * @param Builder $q
  * @param mixed $identifier
  * @return Product
  */
 private function resolveProduct($q, $identifier)
 {
     if (is_string($identifier)) {
         return $q->whereLike($identifier)->firstOrFail();
     } elseif (is_int($identifier)) {
         return $q->findOrFail($identifier);
     }
 }