OAuth2: Returning to App After Logging in - ios

Question

I'm using a cocoapod named (p2/OAuth2) in order to log in an account with GitHub. I'm just playing because I want to know how OAuth2 works.
The following is what I have so far in my view controller (UIViewController).
import UIKit
import p2_OAuth2
class ViewController: UIViewController {
// MARK: - Variables
let oauth2 = OAuth2CodeGrant(settings: [
"client_id": "xxxxxx",
"client_secret": "xxxxxxxx",
"authorize_uri": "https://github.com/login/oauth/authorize",
"token_uri": "https://github.com/login/oauth/access_token", // code grant only
"redirect_uris": ["myapp://oauth/callback"], // register your own "myapp" scheme in Info.plist
"scope": "user repo:status",
"secret_in_body": true, // Github needs this
"keychain": false, // if you DON'T want keychain integration
] as OAuth2JSON)
// MARK: - IBOutlet
// MARK: - IBAction
#IBAction func loginTapped(_ sender: UIBarButtonItem) {
oauth2.logger = OAuth2DebugLogger(.trace)
oauth2.authorize() { authParameters, error in
if let params = authParameters {
print("Authorized! Access token is \(self.oauth2.accessToken ?? "")")
print("Authorized! Additional parameters: \(params)")
}
else {
print("Authorization was cancelled or went wrong: \(String(describing: error))")
}
}
}
// MARK: - Life cycle
override func viewDidLoad() {
super.viewDidLoad()
}
}
What I would like to know is how to get back to the view controller after I successfully log in my account with GitHub. So far, I will be redirected to the URL that I have registered at GitHub's developer website. I suppose I need to register a callback URL scheme under Info. This whole thing is totally new. So I'm not sure how to do it. Thanks.
UPDATE
I have added a set of URL types through info.plist. A URL scheme is set to myapp. And the following is what I have in AppDelegate.
func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey: Any] = [:]) -> Bool {
if url.scheme == "myapp" && url.host == "oauth" {
//oauth2.handleRedirectURL(url)
let storyboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
let controller = storyboard.instantiateViewController(withIdentifier: "HomeView") as! UINavigationController
let viewController = controller.topViewController as! ViewController
window?.rootViewController = viewController
}
window?.makeKeyAndVisible()
return true
}
But the app never calls the above.

Answer 1

I have learnt something new today.
At GitHub's developer website, I have set the call back URL as myapp://oauth/callback. (See below.)
I have created a set of URL schemes through Info.plist. An identifier is made with my reverse domain + a unique name. A URL Schemes item is myapp. (See below.)
Finally, I have added the following line of code to AppDelegate.
func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey: Any] = [:]) -> Bool {
if url.scheme == "myapp" && url.host == "oauth" {
let storyboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
let controller = storyboard.instantiateViewController(withIdentifier: "HomeView") as! UINavigationController
let viewController = controller.topViewController as! ViewController
window?.rootViewController = viewController
}
window?.makeKeyAndVisible()
return true
}
If I log in, I get prompted as follows.
When I tap Open, I'm redirected to my view controller.