Catch the decoding error

DecodingError.swift

let decoder = RPJSONDecoder()
do {
  let response = try decoder.decode(BaseDataArrayResponse<T>.self, from: json)
  completion(response.data, nil)
} catch let DecodingError.dataCorrupted(context) {
  completion(nil, DecodingError.dataCorrupted(context))
  print("codingPath:", context.codingPath)
} catch let DecodingError.typeMismatch(type, context) {
  completion(nil, DecodingError.typeMismatch(type, context))
  print("Type '\(type)' mismatch:", context.debugDescription)
  print("codingPath:", context.codingPath)
} catch let error {
  completion(nil, error)
}