Swift: How to use NSURLSession to query external database? - php

Question

I am writing this question because I am in a big difficulty in understanding how to implement a simple basic authentication login with Swift.
The first screen of my app is a simple form with text fields (username and password) and a Sign In button. In my LoginViewController.swift file I linked the button to this:
#IBAction func doLogin(sender : AnyObject) {
}
The probem now is that I don't know how to go on. I have a local server in MAMP where there is this file.php querying a database and which works perfectly:
<?php
$deep="";
require_once($deep."class/config.php");
$sistema = new config($deep);
if( isset($_GET["username"]) && isset($_GET["password"]) ) {
$username=mysqli_real_escape_string($sistema->dbConn,$_GET["username"]);
$password=mysqli_real_escape_string($sistema->dbConn,$_GET["password"]);
$userL=$sistema->user->allAdmin("WHERE username='".$username."' AND password='".$password."' ");
echo json_encode($userL);
}
?>
So how can I perform a GET request to this file? I suppose I need to create a URL with user data like this form:
http://localhost:8888/excogitoweb/loginM.php?username=lorenzo&password=lorenzo
but then I don't know how to go on. How can I perform this request to retrieve that JSON content? And how can I check that JSON content in order to understand if the sign in procedure has succeeded or has not?
I have watched many tutorials in youtube, overall this but even if I copy the code they show I always get compilation errors...

Answer 1

for a "normal" GET request you need a NSURLRequest with your url... Its just like this:
if let requestURL: NSURL = NSURL(string: "http://localhost:8888/excogitoweb/loginM.php?username=lorenzo&password=lorenzo") as NSURL? {
let urlRequest: NSURLRequest = NSURLRequest(URL: requestURL)
let urlSession = NSURLSession.sharedSession().dataTaskWithRequest(urlRequest, completionHandler: { (data: NSData!, response: NSURLResponse!, error: NSError!) -> Void in
if let responseJSON: [String: String] = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.allZeros, error: nil) as? [String: String] {
///Here you can handle the responded JSON
}
})
urlSession.resume()
}
Don't forget, you are on a background Task when you handle the responded JSON... If you want to do some UI Stuff there you will need to dispatch it to the mein queue
Also a would recommend you doing HTTP POST instead of HTTP GET for such things
UPDATE
if let responseJSON: [[String: String]] = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.allZeros, error: nil) as? [[String: String]] {
///Here you can handle the responded JSON
}