ios - 在 iOS Swift 中执行 POST 请求

Question

我正在尝试执行 POST 请求，但请求没有通过。我已经看过 Perform POST request in Swift已经，但它不包含我正在寻找的内容。

func application(application: UIApplication!, didFinishLaunchingWithOptions launchOptions: NSDictionary!) -> Bool {
    var request = NSMutableURLRequest(URL: NSURL(string: "https://us1.lacunaexpanse.com"))
    println("request url https://us1.lacunaexpanse.com")
    var session = NSURLSession.sharedSession()
    request.HTTPMethod = "POST"

    let apikey = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
    println("apikey",apikey)

    let username = "username"
    let password = "password"

    var login = Array(["username", "password", "apikey"])

    let jsonDictionary = ["2.0", "jsonrpc", "1", "id", "login", "method", "login", "params"]
    println("jsonDictionary",jsonDictionary)

    var writeError: NSError?

    let jsonData = NSJSONSerialization.dataWithJSONObject(jsonDictionary, options: NSJSONWritingOptions(), error: NSErrorPointer())

    var resultAsString = NSString(data: jsonData, encoding: NSUTF8StringEncoding)

    resultAsString = resultAsString.stringByAppendingString("empire")

    let url = NSURL.URLWithString("string")
    println("url",url)

    var request2 = NSMutableURLRequest()
    println("Post url =%@",url)

    request2 = NSMutableURLRequest(URL:url)

    request2.HTTPMethod = "POST"

    var connection = NSURLConnection(request: request, delegate: self, startImmediately: false)

    return true

Answer 1

这里有一大堆战术问题:

1. 您正在创建 URLSession，然后发出 NSURLConnection 请求。只需使用 URLSession。

2. 您的“请求字典”不是字典，而是数组。例如发出JSON-RPC请求，字典的正确格式是:

   let requestDictionary: [String: Any] = [
       "jsonrpc" : "2.0",
       "id"      : 1,
       "method"  : "login",
       "params"  : ["myuserid", "mypassword", "mykey"]
   ]
   

3. 小问题，但是您使用了很多变量(通过 var)，而常量(通过 let)就可以了。本着 Swift 的安全精神，尽可能使用 let。

4. 根据 Lacuna Expanse API ，您的 URL 应该包含模块名称。

   因此，例如，如果在“Empire”模块中执行POST 请求，则URL 是:

   let url = URL(string: "https://us1.lacunaexpanse.com/empire")!
   

5. 您可能会执行大量请求，因此我建议将大部分请求放在一个可以反复调用的函数中，而无需到处重复代码。也许像下面这样的函数采用以下参数:

   • 模块(例如“帝国”与“联盟”)；

   • 方法(例如“登录”与“获取验证码”)；

   • 适合该请求的参数(例如，对于“登录”，这将是“名称”、“密码”和“api_key”)；和

   • 将在异步请求完成时调用的闭包。

   此函数然后准备 JSON-RPC 请求并在请求完成时调用闭包:

   @discardableResult
   func submitLacunaRequest(module: String, method: String, parameters: Any, completion: @escaping (Result<[String: Any], Error>) -> Void) -> URLSessionTask? {
       let session = URLSession.shared
       let url = URL(string: "https://us1.lacunaexpanse.com")!
           .appendingPathComponent(module)
       var request = URLRequest(url: url)
       request.httpMethod = "POST"
       request.setValue("application/json-rpc", forHTTPHeaderField: "Content-Type")
   
       let requestDictionary: [String: Any] = [
           "jsonrpc": "2.0",
           "id"     : 1,
           "method" : method,
           "params" : parameters
       ]
   
       request.httpBody = try! JSONSerialization.data(withJSONObject: requestDictionary)
   
       let task = session.dataTask(with: request) { data, response, error in
   
           // handle fundamental network errors (e.g. no connectivity)
   
           guard error == nil, let data = data else {
               completion(.failure(error ?? URLError(.badServerResponse)))
               return
           }
   
           // check that http status code was 200
   
           guard
               let httpResponse = response as? HTTPURLResponse,
               200 ..< 300 ~= httpResponse.statusCode
           else {
               completion(.failure(URLError(.badServerResponse)))
               return
           }
   
           // parse the JSON response
   
           do {
               guard let responseObject = try JSONSerialization.jsonObject(with: data) as? [String: Any] else {
                   throw URLError(.badServerResponse)
               }
               completion(.success(responseObject))
           } catch let parseError {
               completion(.failure(parseError))
           }
       }
       task.resume()
   
       return task
   }
   

   这会在 JSON-RPC 请求中对方法和参数进行所有必要的包装。然后，您需要做的就是调用该方法:

   submitLacunaRequest(module: "empire", method: "login", parameters: ["myuserid", "mypassword", "mykey"]) { result in
   
       switch result {
       case .failure(let error):
           print("error = \(error)")
   
       case .success(let value):
           if let errorDictionary = value["error"] as? [String: Any] {
               print("error logging in (bad userid/password?): \(errorDictionary)")
           } else if let resultDictionary = value["result"] as? [String: Any] {
               print("successfully logged in, refer to resultDictionary for details: \(resultDictionary)")
           } else {
               print("we should never get here")
               print("responseObject = \(value)")
           }
       }
   }
   

   对于需要字典的请求，例如“创建”，只需提供字典即可:

   submitLacunaRequest(module:"empire", method: "create", parameters: [
       "name"      : "user",
       "password"  : "password",
       "password1" : "password",
       "captcha_guid" : "305...dd-....-....-....-e3706...73c0",
       "captcha_solution" : "42",
       "email" : "test@gmail.com"
   ]) { result in
       switch result {
       case .failure(let error):
           print("error = \(error)")
   
       case .success(let value):
           print("responseObject = \(responseObject)")
       }
   }
   

很明显，在上面这些中，我只是做了最少的错误处理，所以你可以加强这个，但你的问题是关于发出 POST 请求，希望上面说明了这是如何完成的。

有关 Swift 2 版本，请参阅 previous revision这个答案。