GCP Cloud Functions

Google Cloud Functions is a serverless execution environment for building event-driven applications. Write single-purpose functions that respond to HTTP requests, Pub/Sub messages, Cloud Storage events, or Firestore changes — no infrastructure to manage.

Core Concepts

• HTTP Function — triggered by HTTP requests, returns a response
• Event Function — triggered by cloud events (Pub/Sub, Storage, Firestore)
• Gen 2 — latest version, built on Cloud Run, longer timeouts, concurrency
• Trigger — the event source that invokes the function
• Runtime — language environment (Node.js, Python, Go, Java, etc.)

HTTP Functions

// index.js — HTTP function that processes webhook payloads
const functions = require('@google-cloud/functions-framework');