从未调用过 Swift 身份验证挑战 URLSession

Posted 2023-03-14

【中文标题】从未调用过 Swift 身份验证挑战 URLSession

【英文标题】：Swift Authentication Challenge URLSession never called

【发布时间】：2020-01-01 01:17:19

【问题描述】：

我正在尝试访问需要用户名/密码凭据的 API。在调试代码时，我注意到在调用 let session 变量后，它直接进入 session.resume() 并且永远不会调用我的 urlSession 方法来从用户输入中获取用户凭据。

根据我阅读的内容，完成处理程序仍将专门针对身份验证挑战调用委托方法。

运行应用程序不会导致错误，但在后端我得到了这个

“复制匹配凭据时出错。错误=-25300” 和状态码“401”

这是 postReq 函数

func postRequest() 

        let parameters = ["grant_type=authorization_code&code=xyz"]

        guard let url = URL(string: "url to access") else return

        var request = URLRequest(url: url)

        request.httpMethod = "POST"
        request.addValue("xyz", forHTTPHeaderField: "X-API-Key")
        request.addValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
        request.addValue("Basic base64(xyz:xyz)", forHTTPHeaderField: "Authorization")
        guard let httpbody = try? JSONSerialization.data(withJSONObject: parameters, options: []) else return
        request.httpBody = httpbody

        let session = URLSession.shared.dataTask(with: request)  (data, response, error) in
            if let response = response 
                print(response)
            
            if let data = data 
                do 
                    let json = try JSONSerialization.jsonObject(with: data, options: [])
                    print(json)
                 catch 
                    print(error)
                
            
        
        session.resume()
    

直接从 swift 文档获取凭据的委托方法和辅助方法

   func urlSession(_ session: URLSession, task: URLSessionTask, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) 
        let authMethod = challenge.protectionSpace.authenticationMethod
        guard authMethod == NSURLAuthenticationMethodHTTPBasic else 
            completionHandler(.performDefaultHandling, nil)
            return
        
        //Call the completion handler
        guard let credential = credentialFromUI() else 
            completionHandler(.cancelAuthenticationChallenge, nil)
            return
        
        completionHandler(.useCredential, credential)
    

    func credentialFromUI() -> URLCredential? 
        guard let email = emailField!.text, !email.isEmpty,
            let password = passField!.text, !password.isEmpty else 
                return nil
        
        return URLCredential(user: email, password: password, persistence: .forSession)
    

我也是 Swift 和学习的新手，但我觉得我缺少一些微不足道的东西。

【参考方案1】：

如果您在初始请求中提供凭据，则不会请求身份验证质询，因为

request.addValue("Basic base64(xyz:xyz)", forHTTPHeaderField: "Authorization")

您应该删除此行，并在被询问时通过回调提供凭据。