Alamofire返回.Success错误HTTP状态代码

I have a pretty simple scenario that I'm struggling with. I'm using Alamofire to register a user on a rest API. The first call to register is successful and the user can log in. The second call, when trying to register with the same email address should result in a HTTP status code 409 from the server. Alamofire, however, returns a .Success with an empty request and response. I have tested this this API with postman and it correctly returns a 409.

我有一个非常简单的场景，我正在努力。我正在使用Alamofire在rest API上注册用户。第一次注册调用成功，用户可以登录。第二次调用，当尝试使用相同的电子邮件地址注册时，应该从服务器获得HTTP状态代码409。但是，Alamofire会返回一个带有空请求和响应的.Success。我用postman测试了这个API，它正确返回409。

Why is Alamofire not returning .Failure(error), where the error has status code info etc?

为什么Alamofire没有返回.Failure（错误），错误有状态代码信息等？

Here is the call I run with the same input each time.

这是我每次使用相同输入运行的调用。

Alamofire.request(.POST, "http://localhost:8883/api/0.1/parent", parameters: registrationModel.getParentCandidateDictionary(), encoding: .JSON).response(completionHandler: { (req, res, d, e) -> Void in
        print(req, res, d, e)
    })

3 个解决方案

#1

From the Alamofire manual:

来自Alamofire手册：

Validation

验证

By default, Alamofire treats any completed request to be successful, regardless of the content of the response. Calling validate before a response handler causes an error to be generated if the response had an unacceptable status code or MIME type.

默认情况下，无论响应的内容如何，Alamofire都会将任何已完成的请求视为成功。如果响应具有不可接受的状态代码或MIME类型，则在响应处理程序之前调用validate会导致生成错误。

You can manually validate the status code using the validate method, again, from the manual:

您可以再次使用手动验证状态代码：

Alamofire.request(.GET, "https://httpbin.org/get", parameters: ["foo": "bar"])
     .validate(statusCode: 200..<300)
     .validate(contentType: ["application/json"])
     .response { response in
         print(response)
     }

Or you can semi-automatically validate the status code and content-type using the validate with no arguments:

或者，您可以使用不带参数的validate半自动验证状态代码和内容类型：

Alamofire.request(.GET, "https://httpbin.org/get", parameters: ["foo": "bar"])
     .validate()
     .responseJSON { response in
         switch response.result {
         case .success:
             print("Validation Successful")
         case .failure(let error):
             print(error)
         }
     }

#2

If using response, you can check the NSHTTPURLResponse parameter:

如果使用响应，则可以检查NSHTTPURLResponse参数：

Alamofire.request(urlString, method: .post, parameters: registrationModel.getParentCandidateDictionary(), encoding: JSONEncoding.default)
    .response { response in
        if response.response?.statusCode == 409 {
            // handle as appropriate
        }
}

By default, 4xx status codes aren't treated as errors, but you can use validate to treat it as an such and then fold it into your broader error handling:

默认情况下，4xx状态代码不会被视为错误，但您可以使用validate将其视为此错误，然后将其折叠为更广泛的错误处理：

Alamofire.request(urlString, method: .post, parameters: registrationModel.getParentCandidateDictionary(), encoding: JSONEncoding.default)
    .validate()
    .response() { response in
        guard response.error == nil else {
            // handle error (including validate error) here, e.g.

            if response.response?.statusCode == 409 {
                // handle 409 here
            }
            return
        }
        // handle success here
}

Or, if using responseJSON:

或者，如果使用responseJSON：

Alamofire.request(urlString, method: .post, parameters: registrationModel.getParentCandidateDictionary(), encoding: JSONEncoding.default)
.validate()
.responseJSON() { response in
    switch response.result {
    case .failure:
        // handle errors (including `validate` errors) here

        if let statusCode = response.response?.statusCode {
            if statusCode == 409 {
                // handle 409 specific error here, if you want
            }
        }
    case .success(let value):
        // handle success here
        print(value)
    }
}

The above is Alamofire 4.x. See previous rendition of this answer for earlier versions of Alamofire.

以上是Alamofire 4.x.请参阅此前对Alamofire早期版本的回答。

#3

if you use validate() you'll loose the error message from server, if you want to keep it, see this answer https://*.com/a/36333378/1261547

如果您使用validate（），您将从服务器中丢失错误消息，如果您想保留它，请参阅此答案https://*.com/a/36333378/1261547

#1