SwiftUI Authentication Flow

Handle authentication easily with a PassthroughSubject

This is a demo to show how you can do a login flow in SwiftUI. Includes how to take into a View after logged in successfully and how to take back to Login View after logging out from the app.

Used frameworks

-- SwiftUI

-- Combine

Features

• Login

-- On Success -> go to Home View

-- On Fail -> give an Alert

• Logout

-- Go back to Login View

Functionality

AppManager It has the variables to keep track on whether user is Logged In. IsAuthenticated() is returning whether user is logged in by checking the Token is available yet. Authenticated is used as a PassthroughSubject of Bool type. We can send values (true/false) when ever user is logged or logged out. A Group can listen to its changes. It will be coved below

ContentView All View are embedded in a Group. A group can listen to Publishers such as a PassthroughSubject in the onReceive performer and do actions.

LoginView It has two TextFields to get inputs (email/passowrd) and binded to Publishers in its ViewModel. On the Button click, it will run the loginUser() method in the VM.

LoginViewModel This has the logic to check whether login credentials are correct in loginUser() method. For the demo purpose, credentials are hardcoded. If the login is successful, AppManager.Authenticated.send(true) is used. This sends a True value to the PassthroughSubject declared in the AppManager. So any listner is notified. (ContentView Group is listening for changes on this). Also in this method, a UserDefaults value is created with the key token. It is same as the accessToken we use in real apps.

HomeView This is the view shown when user is authenticated. This has a Logout button and triggers logoutUser() method in its VM.

HomeViewModel Once user press on Logout button, logoutUser() is called. It removed the token from the UserDefaults and emmits a false value to AppManagers Authenticated PassthroughSubject.

License

Free to modify/use