Swift Alamofire:如何获取HTTP响应状态代码

Question

我想检索请求失败的HTTP响应状态代码(例如400,401,403,503等)(理想情况下也是成功的).在此代码中,我使用HTTP Basic执行用户身份验证,并希望能够在用户输错密码时向用户发送身份验证失败的消息.

Alamofire.request(.GET, "https://host.com/a/path").authenticate(user: "user", password: "typo")
    .responseString { (req, res, data, error) in
        if error != nil {
            println("STRING Error:: error:\(error)")
            println("  req:\(req)")
            println("  res:\(res)")
            println("  data:\(data)")
            return
        }
        println("SUCCESS for String")
}
    .responseJSON { (req, res, data, error) in
        if error != nil {
            println("JSON Error:: error:\(error)")
            println("  req:\(req)")
            println("  res:\(res)")
            println("  data:\(data)")
            return
        }
        println("SUCCESS for JSON")
}

不幸的是,产生的错误似乎并不表示实际收到了HTTP状态代码409:

STRING Error:: error:Optional(Error Domain=NSURLErrorDomain Code=-999 "cancelled" UserInfo=0x7f9beb8efce0 {NSErrorFailingURLKey=https://host.com/a/path, NSLocalizedDescription=cancelled, NSErrorFailingURLStringKey=https://host.com/a/path})
  req:<NSMutableURLRequest: 0x7f9beb89d5e0> { URL: https://host.com/a/path }
  res:nil
  data:Optional("")
JSON Error:: error:Optional(Error Domain=NSURLErrorDomain Code=-999 "cancelled" UserInfo=0x7f9beb8efce0 {NSErrorFailingURLKey=https://host.com/a/path, NSLocalizedDescription=cancelled, NSErrorFailingURLStringKey=https://host.com/a/path})
  req:<NSMutableURLRequest: 0x7f9beb89d5e0> { URL: https://host.com/a/path }
  res:nil
  data:nil

另外,在发生错误时检索HTTP正文会很好,因为我的服务器端会在那里放置错误的文本描述.

问题
是否可以在非2xx响应时检索状态代码？
是否可以在2xx响应时检索特定的状态代码？
是否可以在非2xx响应时检索HTTP正文？

谢谢!

Answer 1

对于使用Alamofire> = 4.0的Swift 3.x/Swift 4.0用户

response.response?.statusCode

更详细的例子:

Alamofire.request(urlString)
        .responseString { response in
            print("Success: \(response.result.isSuccess)")
            print("Response String: \(response.result.value)")

            var statusCode = response.response?.statusCode
            if let error = response.result.error as? AFError {  
                statusCode = error._code // statusCode private                 
                switch error {
                case .invalidURL(let url):
                    print("Invalid URL: \(url) - \(error.localizedDescription)")
                case .parameterEncodingFailed(let reason):
                    print("Parameter encoding failed: \(error.localizedDescription)")
                    print("Failure Reason: \(reason)")
                case .multipartEncodingFailed(let reason):
                    print("Multipart encoding failed: \(error.localizedDescription)")
                    print("Failure Reason: \(reason)")
                case .responseValidationFailed(let reason):
                    print("Response validation failed: \(error.localizedDescription)")
                    print("Failure Reason: \(reason)")

                    switch reason {
                    case .dataFileNil, .dataFileReadFailed:
                        print("Downloaded file could not be read")
                    case .missingContentType(let acceptableContentTypes):
                        print("Content Type Missing: \(acceptableContentTypes)")
                    case .unacceptableContentType(let acceptableContentTypes, let responseContentType):
                        print("Response content type: \(responseContentType) was unacceptable: \(acceptableContentTypes)")
                    case .unacceptableStatusCode(let code):
                        print("Response status code was unacceptable: \(code)")
                        statusCode = code
                    }
                case .responseSerializationFailed(let reason):
                    print("Response serialization failed: \(error.localizedDescription)")
                    print("Failure Reason: \(reason)")
                    // statusCode = 3840 ???? maybe..
                default:break
                }

                print("Underlying error: \(error.underlyingError)")
            } else if let error = response.result.error as? URLError {
                print("URLError occurred: \(error)")
            } else {
                print("Unknown error: \(response.result.error)")
            }

            print(statusCode) // the status code
    } 

(Alamofire 4包含一个全新的错误系统,详情请看这里)

对于使用Alamofire> = 3.0的Swift 2.x用户

Alamofire.request(.GET, urlString)
      .responseString { response in
             print("Success: \(response.result.isSuccess)")
             print("Response String: \(response.result.value)")
             if let alamoError = response.result.error {
               let alamoCode = alamoError.code
               let statusCode = (response.response?.statusCode)!
             } else { //no errors
               let statusCode = (response.response?.statusCode)! //example : 200
             }
}

Answer 2

在带有参数的完成处理程序中,response我发现http状态代码位于response.response.statusCode:

Alamofire.request(.POST, urlString, parameters: parameters)
            .responseJSON(completionHandler: {response in
                switch(response.result) {
                case .Success(let JSON):
                    // Yeah! Hand response
                case .Failure(let error):
                   let message : String
                   if let httpStatusCode = response.response?.statusCode {
                      switch(httpStatusCode) {
                      case 400:
                          message = "Username or password not provided."
                      case 401:
                          message = "Incorrect password for user '\(name)'."
                       ...
                      }
                   } else {
                      message = error.localizedDescription
                   }
                   // display alert with error message
                 }

Answer 3

    Alamofire
        .request(.GET, "REQUEST_URL", parameters: parms, headers: headers)
        .validate(statusCode: 200..<300)
        .responseJSON{ response in

            switch response.result{
            case .Success:
                if let JSON = response.result.value
                {
                }
            case .Failure(let error):
    }

Answer 4

使用alamofire获取状态代码的最佳方式.

 Alamofire.request(URL).responseJSON {
  response in

  let status = response.response?.statusCode
  print("STATUS \(status)")

}

Answer 5

或者使用模式匹配

if let error = response.result.error as? AFError {
   if case .responseValidationFailed(.unacceptableStatusCode(let code)) = error {
       print(code)
   }
}

Answer 6

在你responseJSON完成，你可以从响应对象，其中有一个类型的状态代码NSHTTPURLResponse?：

if let response = res {
    var statusCode = response.statusCode
}

无论状态码是否在错误范围内，这都将起作用。有关更多信息，请参阅NSHTTPURLResponse文档。

对于其他问题，您可以使用responseString函数获取原始响应正文。您可以添加此元素，responseJSON并且两者都将被调用。

.responseJson { (req, res, json, error) in
   // existing code
}
.responseString { (_, _, body, _) in
   // body is a String? containing the response body
}

Answer 7

您可以通过 alamofire 检查以下代码以获取状态代码处理程序

    let request = URLRequest(url: URL(string:"url string")!)    
    Alamofire.request(request).validate(statusCode: 200..<300).responseJSON { (response) in
        switch response.result {
        case .success(let data as [String:Any]):
            completion(true,data)
        case .failure(let err):
            print(err.localizedDescription)
            completion(false,err)
        default:
            completion(false,nil)
        }
    }

如果状态代码未验证，则将在 switch case 中输入失败

Answer 8

您的错误表明该操作由于某种原因被取消。我需要更多细节才能理解原因。但我认为更大的问题可能是，由于您的端点https://host.com/a/path是伪造的，因此没有真正的服务器响应可供报告，因此您会看到nil.

如果您找到一个提供正确响应的有效端点，您应该会看到一个非零值res（使用 Sam 提到的技术），其形式为NSURLHTTPResponse具有 等属性的对象statusCode。

另外，需要明确的是，它的error类型是NSError。它告诉您网络请求失败的原因。服务器端失败的状态码实际上是响应的一部分。

希望这有助于回答您的主要问题。