objective-c - Swift(或objective-c)相当于curl请求

我想把下面的卷曲请求修改成swift（或obiodic-c）。

curl -X POST \ -d "login_id=mylogin_id" \
-d "api_key=myapi_key" \
https://~~~~~/v2/authenticate/api

以下是我写的。

func authentication(){
    var loginID = "mylogin_id"
    var apiKey = "myapi_key"
    var post:NSString = "login_id=\(loginID)&api_key=\(apiKey)"

    NSLog("PostData: %@",post);

    var url:NSURL = NSURL(string:"https://~~~~~/v2/authenticate/api")!

    var postData:NSData = post.dataUsingEncoding(NSASCIIStringEncoding)!

    var postLength:NSString = String( postData.length )

    var request:NSMutableURLRequest = NSMutableURLRequest(URL: url)
    request.HTTPMethod = "POST"
    request.HTTPBody = postData
    request.setValue(postLength, forHTTPHeaderField: "Content-Length")
    request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
    request.setValue("application/json", forHTTPHeaderField: "Accept")


    var reponseError: NSError?
    var response: NSURLResponse?

    var urlData: NSData? = NSURLConnection.sendSynchronousRequest(request, returningResponse:&response, error:&reponseError)
}

但是，如果登录成功，将返回一个令牌，我无法获取它。

{"auth_token": "ea6d13c7bc50feb46cf978d137bc01a2"}

我提到了this link。
谢谢你的好意。
/////
※更新1月4日PM2:30
我已经重写了“var request~~”中的代码，如下所示，然后得到“error”，因此看起来这段代码将urldata返回为nil。
如果你能找到解决问题的方法，请帮助我。

var request:NSMutableURLRequest = NSMutableURLRequest(URL: url)
    request.HTTPMethod = "POST"
    request.HTTPBody = postData
    //request.setValue(postLength, forHTTPHeaderField: "Content-Length")
    request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
    //request.setValue("application/json", forHTTPHeaderField: "Accept")

    var reponseError: NSError?
    var response: NSURLResponse?
    var urlData: NSData? = NSURLConnection.sendSynchronousRequest(request, returningResponse:&response, error:&reponseError)
    if (urlData != nil){
        var responseData:NSString  = NSString(data:urlData!, encoding:NSUTF8StringEncoding)!
        let res = response as NSHTTPURLResponse!;

        NSLog("Response code: %ld", res.statusCode);

        if (res.statusCode >= 200 && res.statusCode < 300){
            var responseData:NSString  = NSString(data:urlData!, encoding:NSUTF8StringEncoding)!

            NSLog("Response ==> %@", responseData);
        }
    }else{
        NSLog("Error");
    }

最佳答案

我已经通过代表nsurlconnection使用nsurlsession获得了auth令牌，但是我仍然不确定为什么可以使用nsurlsession而不能使用nsurlconnection。
如果你有主意，请告诉我。谢谢你的好意。

func authentication2(){
    let request = NSMutableURLRequest(URL: NSURL(string: "https://~~~/v2/authenticate/api")!)
    request.HTTPMethod = "POST"

    var loginID = "mylogin_id"
    var apiKey = "myapi_key"
    var postString:NSString = "login_id=\(loginID)&api_key=\(apiKey)"

    request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding)
    let task = NSURLSession.sharedSession().dataTaskWithRequest(request) {
        data, response, error in

        if error != nil {
            println("error=\(error)")
            return
        }

        println("response = \(response)")

        let responseString = NSString(data: data, encoding: NSUTF8StringEncoding)
        println("responseString = \(responseString)")
    }
    task.resume()
}