Swift 网络请求与数据解析（JSON与模型互转）

// 注意：解析时json与模型属性个数可以不匹配，但类型必须匹配
struct Respone: Codable {
    let code: Int?
    let message: String?
    let data: TokenData?
}

struct TokenData: Codable {
    let accessToken: String?
    let type: String?
    let expiresAt: Int?
    
    // 注意：json的key和模型属性不同时，可以使用映射
    enum CodingKeys: String, CodingKey {
        case accessToken = "access_token"
        case type
        case expiresAt = "expires_at"
    }
}

// MARK: - Net
private func loadData() {
    // 注意：swift要求集合包含不同类型的值时要显式指定参数类型。
    let parameters: [String : Any] = ["brand":"Apple", "channel":1, "device_id":"123431472xvwerbxcvbvxc", "oaid":"", "os":"17.5.2", "device_mode":"iPhone X"]
    // Foundation 对象转 json data
    let jsonData = try? JSONSerialization.data(withJSONObject: parameters)
    
    let url = URL(string: "https://xxx.xxx.com/api/auth/login/guest")!
    let sessionConfig = URLSessionConfiguration.default
    let session = URLSession(configuration: sessionConfig);
    var request = URLRequest(url: url)
    request.httpMethod = "POST"
    request.httpBody = jsonData
    request.timeoutInterval = 5
    let task = session.dataTask(with: request) { data, response, error in
        if let error = error {
            print("出错了")
            return
        }
        
        guard let httpResponse = response as? HTTPURLResponse, (200...299).contains(httpResponse.statusCode) else {
            print("请求出错了")
            return
        }
        if let mimeType = httpResponse.mimeType, mimeType == "application/json" {
            print("响应json类型")
            if let data = data {
                print("data = \(String(describing: String(data: data, encoding:.utf8)))")
                let decoder = JSONDecoder()
                // jsonData 转 模型
                if let resp = try? decoder.decode(Respone.self, from: data) {
                    print("resp.code = \(String(describing: resp.code))")
                    print("resp.message = \(String(describing: resp.message))")
                    print("resp.accessToken = \(String(describing: resp.data?.accessToken))")
                    print("resp.type = \(String(describing: resp.data?.type))")
                    print("resp.expiresAt = \(String(describing: resp.data?.expiresAt))")
                }
                // 或 jsonData 转 Foundation 对象（即基础数据类型Dictionary, Array等，非自定义类）
                let jsonObj = try? JSONSerialization.jsonObject(with: data)
                print("jsonObj = \(String(describing: jsonObj))")
                if let dict = jsonObj as? Dictionary<String, Any?> {
                    print("code = \(String(describing: dict["code"]))")
                }
            } else {
                print("data 无数据")
            }
        } else {
            print("响应其他类型")
        }
    }
    task.resume()
}

private func loadData1() {
    let url = URL(string: "https://whatsdual.tools-global.com/api/auth/login/guest")!
    let sessionConfig = URLSessionConfiguration.default
    let task = URLSession.shared.dataTask(with: url) { data, response, error in
        if let error = error {
            print("出错了")
            return
        }
        
        guard let httpResponse = response as? HTTPURLResponse, (200...299).contains(httpResponse.statusCode) else {
            print("请求出错了")
            return
        }
        if let mimeType = httpResponse.mimeType, mimeType == "application/json" {
            print("响应json类型")
            if let data = data {
                print("data = \(String(describing: String(data: data, encoding:.utf8)))")
                let decoder = JSONDecoder()
                if let resp = try? decoder.decode(Respone.self, from: data) {
                    print("resp.code = \(String(describing: resp.code))")
                    print("resp.message = \(String(describing: resp.message))")
                    print("resp.data = \(String(describing: resp.data))")
                }
            } else {
                print("data 无数据")
            }
        } else {
            print("响应其他类型")
        }

    }
    task.resume()
}