如何从 API 调用中获取原始 JSON

Question

[注意：为了清楚起见，已对其进行了编辑，因为对于我想要的内容似乎有些混乱。我只想要原始 JSON。在这种情况下，它应该是{"foo":"bar"}。重要的是要强调 我希望这是一个字符串！我不需要将其解码为 Swift 对象或以任何方式编组或修改！]

是否可以从 API 调用中获取原始 JSON？目前我正在使用URLSession.dataTask(with:request)，但响应数据包括响应头和正文。我只想要原始 JSON 作为字符串返回给我。

这是我正在使用的代码：

// Build the URL
var urlComponents = URLComponents()
urlComponents.scheme = "http"
urlComponents.host = "127.0.0.1"
urlComponents.port = 80
urlComponents.queryItems = [URLQueryItem(name: "foo", value: "bar")]
guard let url = urlComponents.url else {
    fatalError("Could not create URL from components")
}

// Configure the request
var request = URLRequest(url: url)
request.httpMethod = "GET"
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")

let task = URLSession.shared.dataTask(with: request) {(responseData, response, error) in
    DispatchQueue.main.async {
        guard error == nil else {
            print("ERROR: \(String(describing: error))")
            return
        }

        guard let _ = response else {
            print("Data was not retrieved from request")
            return
        }

        print("JSON String: \(String(describing: String(data: responseData!, encoding: .utf8)))")

        if let resData = responseData {
            let jsonResponse = try? JSONSerialization.jsonObject(with: resData, options: [])

            if let response = jsonResponse as? [String: Any] {
                print("RESPONSE:")
                dump(response)
            } else {
                print("SOMETHING WENT WRONG")
            }
        }
    }
}

task.resume()

这会在控制台中生成以下内容：

JSON String: Optional("HTTP/1.1 OK\nContent-Type: application/json\n\n{\"foo\":\"bar\"}")
SOMETHING WENT WRONG

Answer 1

您将在完成处理程序Data 参数中找到响应正文。你决定你想用它做什么。

let task = session.dataTask(with: request) { (responseData, response, responseError) in
    guard responseData = responseData else { return }
    print("JSON String: \(String(data: responseData, encoding: .utf8))")
}

Answer 2

也许我把你的问题过于简单化了，但看起来你只是想要一些简单的东西，比如数据到字符串的转换。

let jsonString = String(data: responseData, encoding: .utf8)

Answer 3

您需要序列化响应数据以获取原始 JSON：

URLSession.shared.dataTask(with: urlRequest) { (responseData, response, error) in

    // check for errors, then...

    if let resData = responseData {                    
        let jsonResponse = try? JSONSerialization.jsonObject(with: resData, options: [])

        if let response = jsonResponse as? [String: Any] {
             // ... handle response
        }
    }
}