如何从Alamofire错误中获得底层错误?
对于这种请求:如何从Alamofire错误中获得底层错误?
Alamofire.request("https://google.com").responseCollection { (response: DataResponse<[User]>) in
guard response.result.isSuccess else {
print(response.error)
return
}
}
我看到该印刷在控制台:
可选(my_app_name.BackendError.jsonSerialization(Alamofire.AFError.responseSerializationFailed(Alamofire.AFError.ResponseSerializationFailureReason .jsonSerializationFailed(错误 域= NSCocoaErrorDomain代码= 3840“字符周围的值无效 0.”UserInfo = {NSDebugDescription =字符0周围的值无效}))) )
我已经试过:
Alamofire.request("https://google.com").responseCollection { (response: DataResponse<[User]>) in
guard response.result.isSuccess else {
print(response.error)
if let error1 = response.error as? AFError {
print(error1) // Execution DOES NOT reach here.
}
if let error2 = response.error as? BackendError {
print(error2) // Execution DOES reach here.
}
return
}
}
print(error2)
上面打印:
jsonSerialization(Alamofire.AFError.responseSerializationFailed(Alamofire.AFError.ResponseSerializationFailureReason.jsonSerializationFailed(错误 Domain = NSCocoaErrorDomain Code = 3840“字符周围的值无效 0.”UserInfo = {NSDebugDescr在字符0 iption =无效值})))
我想要做的就是在底层的错误,所以我可以解析domain
,code
和userInfo
性能。
我创建BackendError
枚举该Alamofire提供作为一个例子在https://github.com/Alamofire/Alamofire#handling-errors:
enum BackendError: Error {
case network(error: Error) // Capture any underlying Error from the URLSession API
case dataSerialization(error: Error)
case jsonSerialization(error: Error)
case xmlSerialization(error: Error)
case objectSerialization(reason: String)
}
和我还实施了例如通用响应对象序列完全一样,例如在https://github.com/Alamofire/Alamofire#generic-response-object-serialization:
extension DataRequest {
@discardableResult
func responseCollection<T: ResponseCollectionSerializable>(
queue: DispatchQueue? = nil,
completionHandler: @escaping (DataResponse<[T]>) -> Void) -> Self {
let responseSerializer = DataResponseSerializer<[T]> { request, response, data, error in
guard error == nil else {
return .failure(BackendError.network(error: error!))
}
let jsonSerializer = DataRequest.jsonResponseSerializer(options: .allowFragments)
let result = jsonSerializer.serializeResponse(request, response, data, nil)
guard case let .success(jsonObject) = result else {
return .failure(BackendError.jsonSerialization(error: result.error!))
}
guard let response = response else {
let reason = "Response collection could not be serialized due to nil response."
return .failure(BackendError.objectSerialization(reason: reason))
}
return .success(T.collection(from: response, withRepresentation: jsonObject))
}
return response(responseSerializer: responseSerializer, completionHandler: completionHandler)
}
}
我认为有switch
es,case
s,并且从BackendError
,AFError
,Error
,和/或NSError
,但我似乎无法得到它。
如何获取底层错误,以便我可以解析domain
,code
和userInfo
属性?
我使用的是Swift 3和Alamofire 4.3.0。
看response.result
:
if case let .failure(error) = response.result {
let error = error as NSError
print("\(error.domain)")
print("\(error.code)")
print("\(error.userInfo)")
}
什么是你尝试获得无效响应 –
我想接收特定错误时做一些事情的目的。 – Daniel
这是无效的JSON错误,那么你将如何处理 –