How to make HTTP post request with specific body? And how to access token from the server to allow me to login? - authentication

Question

I'm having a scenario like :
1) I want to create Http POST request and for this I'm having the data, please see this image:
2) As you can see in the above image, I have to create post a request with the mentioned body and also I'm getting response named: token. How to create post request and fetch this token response?.
3) That token response will allow me to login into myapp.
I'm newbie to this scenario. I have tried some code by my own but still getting confuse in how to combine my app delegate code with this POST Request Code.
Code
#IBAction func signinaction(_ sender: Any) {
self.username.resignFirstResponder()
self.password.resignFirstResponder()
if (self.username.text == "" || self.password.text == "") {
let alertView = UIAlertController(title: "Login failed",
message: "Wrong username or password." as String, preferredStyle:.alert)
let okAction = UIAlertAction(title: "Try Again!", style: .default, handler: nil)
alertView.addAction(okAction)
self.present(alertView, animated: true, completion: nil)
return
}
// Check if the user entered an email
if let actualUsername = self.username.text {
// Check if the user entered a password
if let actualPassword = self.password.text {
// Build the body message to request the token to the web app
self.bodyStr = "username=8870417698&password=1234&grant_type=password" + actualUsername + "&password=" + actualPassword
// Setup the request
let myURL = NSURL(string: "http://ezschoolportalapi.azurewebsites.net/token")!
let request = NSMutableURLRequest(url: myURL as URL)
request.httpMethod = "POST"
request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
request.setValue("application/json", forHTTPHeaderField: "Accept")
request.httpBody = bodyStr.data(using: String.Encoding.utf8)!
let task = URLSession.shared.dataTask(with: request as URLRequest) {
(data, response, error) -> Void in
if data?.count != 0
{
do {
let tokenDictionary:NSDictionary = try JSONSerialization.jsonObject(with: data!, options:.allowFragments) as! NSDictionary
print(tokenDictionary)
// Get the token
let token:String = tokenDictionary["access_token"] as! String
// Keep record of the token
let userdefaults = UserDefaults()
let saveToken = userdefaults.set(token, forKey: "access_token")
userdefaults.synchronize()
// Dismiss login view and go to the home view controller
DispatchQueue.main.async {
self.dismiss(animated: true, completion: nil)
}
}
catch {
// Wrong credentials
// Reset the text fields
self.username.text = ""
self.password.text = ""
// Setup the alert
let alertView = UIAlertController(title: "Login failed",
message: "Wrong username or password." as String, preferredStyle:.alert)
let okAction = UIAlertAction(title: "Try Again!", style:.default, handler: nil)
alertView.addAction(okAction)
self.present(alertView, animated: true, completion: nil)
return
}
}
}
task.resume()
}
}
}
Question is how to combine this code with my above code :
let appDelegate = UIApplication.shared.delegate as! AppDelegate appDelegate.gotoMainvc()
if I use directly this code then in any of the case I'm able to switch over to my home screen it doesn't matter whether m using this POST Request code or not. Please Help.

Answer 1

You are hard coding the username and password in bodyStr update it to
self.bodyStr = "username=" + actualUsername + "&password=" + actualPassword + "&grant_type=password"
Update the statements inside do with
do {
let tokenDictionary:NSDictionary = try JSONSerialization.jsonObject(with: data!, options:.allowFragments) as! NSDictionary
print(tokenDictionary)
// Get the token
if let authToken = tokenDictionary["access_token"] as? String{
self.token = authToken
UserDefaults.standard.set(accessToken, forKey: "access_token")
UserDefaults.standard.synchronize()
DispatchQueue.main.async {
self.dismiss(animated: true, completion: nil)
}
}
}
You can implement a function like isUserLoggedIn which will return true if token is saved in userDefaults. You need to check whether the user has logged in in the appDelegate's applicationdidFinishLaunchingWithOptions.Like
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
if isUserLoggedIn(){
//showHomeViewController
} else{
//showLoginViewController
}
return true
}
func isUserLoggedIn() -> Bool{
if let accessToken = UserDefaults.standard.object(forKey: "access_token") as? String {
if (accessToken.characters.count)! > 0{
return true
} else {
return false
}
}
else {
return false
}
}