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对于此请求:
Alamofire.request("https://google.com").responseCollection { (response: DataResponse<[User]>) in
guard response.result.isSuccess else {
print(response.error)
return
}
}
我在控制台中看到这个打印:
Optional(my_app_name.BackendError.jsonSerialization(Alamofire.AFError.responseSerializationFailed(Alamofire.AFError.ResponseSerializationFailureReason.jsonSerializationFailed(Error Domain=NSCocoaErrorDomain Code=3840 "Invalid value around character 0." UserInfo={NSDebugDescription=Invalid value around character 0.}))))
我尝试过的:
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)
以上打印:
jsonSerialization(Alamofire.AFError.responseSerializationFailed(Alamofire.AFError.ResponseSerializationFailureReason.jsonSerializationFailed(Error Domain=NSCocoaErrorDomain Code=3840 "Invalid value around character 0." UserInfo={NSDebugDescription=Invalid value around character 0.})))
我想做的是找出潜在的错误,这样我就可以解析 domain
, code
, 和 userInfo
属性。
我创建了 BackendError
Alamofire 在 https://github.com/Alamofire/Alamofire#handling-errors 提供的枚举示例:
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)
}
我还实现了示例通用响应对象序列化,与 https://github.com/Alamofire/Alamofire#generic-response-object-serialization 中的示例完全一样:
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
是的,case
s,并转换为 BackendError
, AFError
, Error
, 和/或 NSError
, 但我似乎无法理解。
我怎样才能找到潜在的错误,以便我可以解析 domain
, code
, 和 userInfo
属性?
我正在使用 Swift 3 和 Alamofire 4.3.0。
最佳答案
对于 Alamofire 4.3,查看 response.result
:
if case let .failure(error) = response.result {
let error = error as NSError
print("\(error.domain)")
print("\(error.code)")
print("\(error.userInfo)")
}
关于ios - 如何从 Alamofire 错误中获取底层错误?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/42591945/
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