Complete login screen with backend included for Kivy apps using Firebase for user authentication.

This package lets you essentially drop a functional login screen into your app within seconds.

pip install firebaseloginscreen

• Create account
• Email verification for new accounts
• Sign in to account
• Log out of account
• Reset password
• Automatically signs users in upon app launch if an account has already been created.

Psst. Want to just see a full example? Check out main.py and main.kv in the examples directory.

In the kv file where you want to use the login screen, import the FirebaseLoginScreen widget:

#:import FirebaseLoginScreen firebaseloginscreen.firebaseloginscreen.FirebaseLoginScreen

Then add the FirebaseLoginScreen widget to your ScreenManager class, wherever that may be. Here's a snippet of the code you should add to your ScreenManager:

    # ---- This should be within a ScreenManager
    FirebaseLoginScreen:
        id: firebase_login_screen
        name: "firebase_login_screen"
        debug: True
        remember_user: True
        require_email_verification: True
        web_api_key: "your_web_api_key_from_firebase" # Found in Firebase -> Project Settings -> Web API Key
        background: "background.jpg"
        on_login_success:
            # Defining this function lets you program what to do when the
            # user has logged in (probably you'll want to change screens)!
            # Get the important user info
            if self.login_state == 'in': app.user_localId = self.localId
            if self.login_state == 'in': app.user_idToken = self.idToken
            if self.login_state == "in": print("User logged in")
            
            if self.login_state == 'out': print("User logged out")
    # ---- Other screens in your app should be down here (below the FirebaseLoginScreen)

Make sure the FirebaseLoginScreen is the first screen in your ScreenManager.

Need help figuring out the setup related to Firebase? Check out these instructions.

You should define the on_login_success function to execute whatever code you want once a user has logged in. Probably you'll want to 1) Retrieve some data from Firebase and 2) switch to a different screen in your ScreenManager.

If a user has already signed in, it will store their login data and automatically sign them in the next time around. In this case, the login screens will not be shown, and your app will immediately do whatever you have coded it to do in the on_login_success function of the FirebaseLoginScreen.

Typically, when making requests to your database to get data for your user, you identify the user by their localId. You can use the idToken to authenticate a user's request to the database if you have set up Firebase Rules. Both of these variables are automatically retrieved for you by FirebaseLoginScreen.

Need to allow your users to sign out? To do so, reference your FirebaseLoginScreen widget (using an id) and call the .log_out() function. Then have your ScreenManager switch to the FirebaseLoginScreen to allow your user to sign in again.

If your app takes a long time to start up, you may need to set the web_api_key from python instead of in the kv language. You need to set it in the on_start method of your App class. Haven't fully characterized this race condition yet.

• Boolean SMS Verification (for phone sign ins)
• Sign in method choice
  • email, phone