Post Sign-up Event with Google Calendar

This sample demonstrates how to use an Auth blocking function to save a user's Google OAuth2 access token to Firestore upon sign-up. It then uses a task queue to schedule a Cloud Function that uses this token to create a Google Calendar event for the user.

Functions Code

See file functions/main.py for the code.

The function savegoogletoken is an Auth blocking function that triggers before a user is created. If the user is signing up with Google, it saves their OAuth2 access token to a user_info collection in Firestore. It then creates a task to call the scheduleonboarding function.

The scheduleonboarding function is a task queue function that retrieves the user's access token from Firestore, creates a new event on their primary Google Calendar, and then deletes the access token from Firestore.

Trigger rules

• The savegoogletoken function is triggered by beforeUserCreated Auth blocking event.
• The scheduleonboarding function is triggered by a task queue.

Deploy and test

To deploy and test the sample:

1. Create a Firebase project on the Firebase Console.
2. Enable the Google Calendar API for your project in the Google Cloud Console.
3. Enable blocking functions for your project in the Firebase console:
   • Go to the Authentication > Settings page.
   • In the Blocking functions section, select Before user creation (beforeCreate) from the dropdown menu.
   • Ensure that Enable credential pass-through is checked.
4. Get the code, for instance using git clone https://github.com/firebase/functions-samples
5. Enter the correct directory cd functions-samples/Python/post-signup-event
6. Set up the CLI to use your Firebase project using firebase use --add and select your Firebase project.
7. Deploy your project's code using firebase deploy.
8. Sign up for your app using a Google account.
9. After a minute, check your Google Calendar for a new "Onboarding with ExampleCo" event.