通过 Swift 发送 POST 请求

Question

我在后端使用 Stripe API 来处理付款。 这是 API URL：http://localhost:2000/charge/new

我正在为我的 iOS 应用程序使用 SwiftUI 来向我的 API 发送 POST 请求。

这是我的 DTO 对象：

DTO：

struct ChargeObjectDTO : Codable{
    let vendorCustomerID: String;
    let currency: String;
    let chargeValue: CLongDouble;
    let confirmationStatus: Bool;
}

这是我的请求逻辑，我正在尝试以 ChargeObjectDTO 作为对象发送 POST 请求：

支付API：

    func createChargeRequest(chargeObj: ChargeObjectDTO) throws {
     
        var url = “http://localhost:2000/charge/new"
    
        do{
            //send request
            guard let myReqURL = URL(string: url) else { throw NetworkResponse.error };
            
            //Request
            var request = URLRequest(url: myReqURL);
            request.httpMethod = "POST";
            request.httpBody = try? JSONSerialization.data(withJSONObject: chargeObj);
            
            request.setValue("application/json", forHTTPHeaderField: "Content-Type")
            request.setValue("token", forHTTPHeaderField: "Authorization")   //Here is where we add tokens, like authentication tokens
            
           
            URLSession.shared.dataTask(with: request, completionHandler: { (data, response, error) in
                    guard let httpResponse = response as? HTTPURLResponse,
                          httpResponse.statusCode == 200,
                          let myData = data,
                          let myJson = try? JSONSerialization.data(withJSONObject: data!, options: []) else{
                        let message = error?.localizedDescription ?? "Failed to Decode Response from Server"
                        print(message)
                        return
                    }
                    print("Created Payment Intent");
                    //DispatchQueue.main.async
                    
                }).resume();
                
                
                
        }catch{
            print(error)
        }
      
        
       
    }

这是 UI 屏幕 预订酒店：

    struct HotelBookingScreen: View {

        @State var myPaymentsAPI: PaymentsAPI = PaymentsAPI.init(chargeObjectDTO: ChargeObjectDTO(vendorCustomerID: "", currency: "", chargeValue: 0, confirmationStatus: false));
    
  

        var body: some View {

            Button(action: {
                                    try? myPaymentsAPI.createChargeRequest(chargeObj: ChargeObjectDTO(vendorCustomerID: "cus_12345”, currency: "USD", chargeValue: 100, confirmationStatus: true))
                                    
                                },  label: {
                                    Text("Confirm")
                                        .frame(maxWidth: 300)
                     });

        }
    }

问题是什么，为什么我会收到此错误，即使我正在解码 JSON 对象？

我收到的错误是：

由于未捕获的异常“NSInvalidArgumentException”而终止应用程序，原因：“*** +[NSJSONSerialization dataWithJSONObject:options:error:]：JSON 写入中的顶级类型无效”

Answer 1

这是我解决问题的方法，希望对某人有帮助。

代码：

class PaymentsAPI: ObservableObject{

let paymentsAPI = URL.paymentsAPIURL;

var endpoint: String;


init(endpoint: String) {
    self.endpoint = endpoint
}



func createChargeRequest(chargeObj: ChargeObjectDTO, completion: @escaping(Result<ChargeObjectDTO, NetworkResponse>) -> Void) {
 
    //var myURL = "\(paymentsAPI)/charges/vendor/charge/new"

    let myURL = "\(paymentsAPI)\(endpoint)"


    do{
        guard let reqURL = URL(string: myURL) else{ throw NetworkResponse.error }
        //Request
        var request = URLRequest(url: reqURL);
        request.httpMethod = "POST";
        request.addValue("application/json", forHTTPHeaderField: "Content-Type")
        request.httpBody = try JSONEncoder().encode(chargeObj)
        
        
        let dataTask = URLSession.shared.dataTask(with: request){ data, response, error in
            guard let myHttpResponse = response as? HTTPURLResponse, myHttpResponse.statusCode == 200,
                  let jsonData = data else{
                completion(.failure(NetworkResponse.error))
                return
            }
            
            do{
                let messageData = try JSONDecoder().decode(ChargeObjectDTO.self, from: jsonData)
                completion(.success(messageData))
            }catch{
                completion(.failure(.error))
            }
        }
        
        dataTask.resume()

    }catch{
        completion(.failure(.error))
    }
    
}

}