Изпращане на POST заявка в swift 2

Създавам приложение за влизане и когато някога намеря начин да изпратя POST заявка до php и го опитам, има или грешка, или няма грешки, но не изпълнява моя php скрипт. Благодаря предварително. Използвам mac с OS X El Capitan с XCODE 7 и Swift 2. Сървърът ми е стар Windows компютър с WAMPServer.

    import UIKit
 class Login: UIViewController {
@IBOutlet weak var UserName: UITextField!
@IBOutlet weak var PassWord: UITextField!
override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?){
      UserName.resignFirstResponder()
    view.endEditing(true)
    super.touchesBegan(touches, withEvent: event)
}
   @IBAction func LoginTapped(sender: AnyObject) {
    var UserNameEntered = UserName.text
    var PassWordEntered = PassWord.text
    let ClientUserNameStored = NSUserDefaults.standardUserDefaults().stringForKey("UserName");
    let ClientPassWordStored = NSUserDefaults.standardUserDefaults().stringForKey("PassWord");
    if(ClientUserNameStored != UserNameEntered && PassWordEntered != ClientPassWordStored || ClientUserNameStored != UserNameEntered && PassWordEntered == ClientPassWordStored || ClientUserNameStored == UserNameEntered && ClientPassWordStored != PassWordEntered){
        print("Not equal")
        var Alert = UIAlertController(title: "Warning", message: "Invalid username or password!", preferredStyle: UIAlertControllerStyle.Alert)

        Alert.addAction(UIAlertAction(title: "OK", style: .Default, handler: { (action: UIAlertAction!) in UserNameEntered = ""; PassWordEntered = "";
        }))
        presentViewController(Alert, animated: true, completion: nil)
    }else{
        let request = NSMutableURLRequest(URL: NSURL(string: "http://host/my/file.php")!)
        request.HTTPMethod = "POST"
        let postString = "username=\(UserNameEntered)&password=\(PassWordEntered)"
        request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding)
        let task = NSURLSession.sharedSession().dataTaskWithRequest(request) {
            data, response, error in

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

            print("response = \(response)")

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

                  self.performSegueWithIdentifier("GoToHome", sender: self)

    }
}

}

Моят PHP код е по-долу.

<?php
$postVar = $_POST['username'];
$postVartwo = $_POST['password'];
$file = fopen("test.txt", "a");
echo fwrite($file, $postVar."pass".$postVartwo);
fclose($file);
?>