Cloud Functions for Firebase Sample Library
This repository contains a collection of samples showcasing some typical uses of Cloud Functions for Firebase.
Samples are available for Node (1st and 2nd gen) and Python (2nd gen).
What's Cloud Functions for Firebase?
Cloud Functions is a hosted, private, and scalable environment where you can run JavaScript or Python code. Cloud Functions for Firebase integrates the Firebase platform by letting you write code that responds to events and invokes functionality exposed by other Firebase features.
Prerequisites
All samples require the Blaze pay-as-you-go billing plan to deploy. Learn more about pricing.
To learn how to get started with Cloud Functions for Firebase by having a look at the Getting Started Guide, trying the quickstart samples and looking at the documentation.
Quickstarts
Minimal samples for each Cloud Functions trigger type.
Quickstart: Uppercaser for Firestore
- Node 2nd gen
- Python
- Node 1st gen
This quickstart sample demonstrates using Cloud Functions triggered by Firestore events. The function transforms message text written to Firestore to uppercase.
Quickstart: Add numbers and sanitize text with callable functions
- Dart
- Node 2nd gen
- Python
- Node 1st gen
Quickstart: Stream responses with callable functions
HTTPS trigger quickstart: Time Server
- Dart
- Node 2nd gen
- Python
- Node 1st gen
This quickstart sample demonstrates using Cloud Functions triggered by HTTPS requests. The function returns the current server time and allows for date time formatting.
Quickstart: Uppercaser for Realtime Database
- Node 2nd gen
- Python
- Node 1st gen
This quickstart sample demonstrates using Cloud Functions triggered by Realtime Database events. The function transforms message text written to Realtime Database to uppercase.
Hosting triggered HTTPS function quickstart: Big Ben
This quickstart demonstrates using Cloud Functions with an HTTPS trigger that's triggered by a Firebase Hosting URL. The function will display a repeated number of "BONG"s depending on the hour of the day.
Cloud Storage trigger quickstart: Thumbnail generator
- Node 2nd gen
- Python
- Node 1st gen
This quickstart sample demonstrates using Cloud Functions triggered by Firebase Storage events. The function generates a thumbnail of uploaded images.
Auth trigger quickstart: Welcome Email
- Node 2nd gen
- Node 1st gen
This quickstart sample demonstrates using Cloud Functions triggered by Firebase Auth events. The function sends a Welcome Email when user accounts are created (or when users sign-in using an Identity Provider for the first time) and sends a Goodbye Email when user accounts are deleted.
Auth blocking trigger quickstart: Validate and check user status
- Node 2nd gen
- Python
- Node 1st gen
This quickstart demonstrates using Auth blocking functions to validate a user's email before they are allowed to sign in, and to see if a user is part of a list of banned users in Firestore.
PubSub trigger quickstart: Hello World
- Node 2nd gen
- Python
- Node 1st gen
This quickstart sample demonstrates using Cloud Functions triggered by PubSub events. The functions log the PubSub payload in a Hello world message.
Test Lab trigger quickstart: Log when a matrix completes
Firebase Alerts trigger quickstart: Send crash reports to Discord
- Node 2nd gen
- Python
- Node 1st gen: not supported
Trigger a function based on a Firebase Alert, and send information about the alert to a channel in a Discord server.
Custom Events: Save image metadata
- Node 2nd gen
- Python
- Node 1st gen: not supported
Learn how to trigger a function based on an event sent by an extension
Unit testing
- Test with Jest
- Test with Jest and TypeScript
- Test with Mocha
Development Boilerplates
The Firebase CLI generates sample code for Cloud Functions using JavaScript or TypeScript.
Server-side generated pages w/ Handlebars templating and user sessions
This sample shows how to serve server-side generated HTML pages using the HandlebarsJs templating system and serve user-specific content by always passing the Firebase ID token in a __session cookie.
Image Processing
Here are a few samples that show how you can process or analyze images using Cloud Functions.
Image Maker
This sample demonstrates how to create various customized images such as sparkline or sphere charts through Cloud Functions and Hosting and serve it to the client.
Uses an HTTP trigger.
Convert images after upload
Demonstrates how to automatically convert images that are uploaded to Firebase Storage to JPEG using ImageMagick.
Uses a Firebase Storage trigger.
Moderate offensive images
Demonstrates how to automatically moderate offensive images that are uploaded to Firebase Storage by using the Google Cloud Vision API to detect offensive images and ImageMagick to blur these images.
Uses a Firebase Storage trigger.
Extract image metadata
Demonstrates how to automatically extract image's metadata using ImageMagick for images that are uploaded to Firebase Storage.
Uses a Firebase Storage trigger.
Task Queues: back up images from an API
See how to use Task Queues to meter traffic to a rate-limited API.
Firebase Realtime Database Data Consistency
These samples show how to implement automatic data consistency such as keeping a count of children, having a max amount of node childs, cleaning up old data etc...
LastModified Firebase Realtime Database tracking
Tracking when the Firebase Database (or a subset) was last modified.
Uses a Realtime Database trigger.
Firebase Database child nodes count
Keeps track of the number of child nodes of a Firebase Database element allowing clients to filter or order results using the child count.
This can be useful to keep track of the number of "likes" or "followers" of something shared through social media.
Uses a Realtime Database trigger.
Limit number of child nodes
Makes sure that the number of child nodes stays below a certain threshold. This can be useful to limit the number of lines of logs or chat history below a given number.
Uses a Realtime Database trigger.
Removing old items from a list
This sample shows how to remove child nodes older than 2 hours from a Firebase Database list. This can be useful for removing outdated items from a collection.
Uses a Realtime Database trigger.
Solve other common use cases
Send FCM notifications
This sample demonstrates how to send a Firebase Cloud Messaging (FCM) notification from a Realtime Database triggered Function when users get new followers. The sample also features a Web UI to experience the FCM notification.
Uses a Realtime Database trigger.
Authenticated JSON API
This sample shows how to authenticate access to a JSON API to only allow access to data for a specific Firebase user.
Uses an HTTP trigger.
Authorized HTTP endpoint
This sample shows how to restrict an HTTPS Function to only the Firebase users of your app.
Only users who pass a valid Firebase ID token as a Bearer token in the Authorization header of the HTTP request or in a __session cookie are authorized to use the function.
Checking the ID token is done with an ExpressJs middleware that also passes the decoded ID token in the Express request object.
Uses an HTTP trigger.
Authorize with 3rd-party authentication providers
Okta, LinkedIn, Spotify, or Basic Auth
Demonstrates how to authorize with a 3rd party sign-in mechanism, create a Firebase custom auth token, update the user's profile and authorize Firebase.
Uses an HTTP trigger.
Post GitHub commits to Slack channel
Demonstrates how to automatically post GitHub commits to a Slack channel using an HTTPS triggered Function.
Create and charge customers with Stripe
Demonstrates how to integrate Firebase Auth and Cloud Firestore with Stripe via the Stripe Node.js library.
Text moderation
Demonstrates how to moderate user input text for bad words. This can be used to moderate usernames, chat or forum messages.
Uses a Realtime Database trigger.
Email confirmation
Sends email confirmation after users subscribed to a mailing list.
Uses a Realtime Database trigger.
Automatic message translation
Integrates the Google Translate API to perform automatic text translation across any number of languages. Language codes can be stored in Firebase for on the fly changes.
Uses a Realtime Database trigger.
Automatic URL shortener
Integrates the Bit.ly API to shorten URLs automatically as they are added to the database.
Uses a Realtime Database trigger.
Full-text search for Realtime Database or Firestore
Enable full-text search on Firebase Database data or Firestore documents by using a hosted search service.
Uses a Realtime Database or Firestore trigger.
User data cleanup
This sample moved to FirebaseExtended/user-data-protection, which is kept for reference and no longer maintained. To delete a user's data when they delete their account, use the Delete User Data extension.
Export your data to a Google Spreadsheet
This sample demonstrates how to sync new data written to a Firebase database to a Google Sheet. It includes a method for obtaining, storing, and using Oauth2 tokens for Google API access.
Uses HTTPS triggers and Realtime Database triggers.
Export your data to Big Query
Copies Firebase Database elements into BigQuery automatically. This can be useful for instance for further logs analysis.
Uses a Realtime Database trigger.
Webhook upon Firebase Database writes
Writing to the Firebase Database triggers a request to a callback URL (a Webhook). The content of the modified Data is sent to the Webhook.
Uses a Realtime Database trigger.
Send a survey when users update your app
This sample shows how to send a survey to your users who have updated your app. App Update is detected using a Firebase Analytics event.
Uses an Analytics trigger.
Send a coupon to user who have completed a purchase
This sample shows how to send a coupon to your users who have just purchased something. 10% off on your next purchase!
Uses an Analytics trigger.
Delete inactive users accounts via cron
Periodically deletes the accounts of users who have not signed in in the last month.
Uses an HTTPS trigger.
Developer Motivator
This sample demonstrates how to send a Firebase Cloud Messaging (FCM) notification to the developer device each time your app gains or loses a user.
Uses an Analytics trigger.
Audio Files Conversion
This sample uses ffmpeg / fluent-ffmpeg and automatically converts audio files that are uploaded to Cloud Storage to FLAC file format with mono-channel audio @ 16000hz.
Uses a Storage trigger.
Presence for Firestore
Build a simple online / offline status indicator for your users by leveraging Firestore and Realtime Database together.
Uses a Realtime Database trigger.
Publish Models to Firebase ML
Automatically publishes models to Firebase ML for each TensorFlow Lite file that is uploaded to Firebase Storage.
Get information about a YouTube channel
This sample shows how to query the Youtube Data API.
Uses an HTTPS trigger.
Contributing
We'd love that you contribute to the project. Before doing so please read our Contributor guide.
License
© Google, 2015-2026. Licensed under an Apache-2 license.
Build Status
/functions-samples