Send Firebase Cloud Messaging notifications for new followers.
This sample demonstrates how to send a Firebase Cloud Messaging (FCM) notification from a Realtime Database triggered Function. The sample also features a Web UI to experience the FCM notification.
See file functions/index.js for the code.
Sending the notification is done using the Firebase Admin SDK. The Web client writes the individual device tokens to the realtime database which the Function uses to send the notification.
The dependencies are listed in functions/package.json.
Sample Database Structure
Users sign into the app and are requested to enable notifications on their browsers. If they successfully enable notifications the device token is saved into the datastore under
/functions-project-12345 /users /Uid-12345 displayName: "Bob Dole" /notificationTokens 1234567890: true photoURL: "https://lh3.googleusercontent.com/..."
If a user starts following another user we'll write to
/functions-project-12345 /followers /followedUid-12345 followerUid-67890: true /users /Uid-12345 displayName: "Bob Dole" /notificationTokens 1234567890: true photoURL: "https://lh3.googleusercontent.com/..."
The function triggers every time the value of a follow flag changes at
Deploy and test
This sample comes with a web-based UI for testing the function. To test it out:
- Create a Firebase Project using the Firebase Console.
- Enable Google Provider in the Auth section
- Clone or download this repo and open the
- You must have the Firebase CLI installed. If you don't have it install it with
npm install -g firebase-toolsand then configure it with
- Configure the CLI locally by using
firebase use --addand select your project in the list.
- Install dependencies locally by running:
cd functions; npm install; cd -
- Deploy your project using
- Open the app using
firebase open hosting:site, this will open a browser.
- Start following a user, this will send a notification to him.