Cloud Functions - Cloud Pub/Sub Trigger¶

Step-01: Introduction¶

Create Cloud Pub/Sub Topic
Create Cloud Function with Cloud Pub/Sub Events Trigger

Step-02: Create Cloud Pub/Sub Topic¶

Go to Cloud Pub/Sub -> CREATE TOPIC
Topic ID: mytopic1
REST ALL LEAVE TO DEFAULTS
Click CREATE
Review Pub/Sub Topics and Subscriptions
Review Topic
Review Subscription

Step-03: Create Cloud Function with Cloud Pub/Sub Event Trigger¶

Go to Cloud Functions -> CREATE

1. Configuration Tab¶

Environment: 2nd gen
Function name: cf-demo2-events-pubsub
Region: us-central1
Trigger: Cloud Pub/Sub
Cloud Pub/Sub Topic: mytopic1
Click on MORE OPTIONS and review the settings
REST ALL LEAVE TO DEFAULTS
Click to NEXT

2. Code Tab¶

Runtime: Nodejs20 (default as on today)
LEAVE THE AUTO-POPULATED CODE AS-IS.

JUST REVIEW THE CODE and Click on DEPLOY

const functions = require('@google-cloud/functions-framework');

// Register a CloudEvent callback with the Functions Framework that will
// be executed when the Pub/Sub trigger topic receives a message.
functions.cloudEvent('helloPubSub', cloudEvent => {
  // The Pub/Sub message is passed as the CloudEvent's data payload.
  const base64name = cloudEvent.data.message.data;

  const name = base64name
    ? Buffer.from(base64name, 'base64').toString()
    : 'World';

  console.log(`Hello, ${name}!`);
});

Step-04: Review Cloud Function Logs¶

Go to Cloud Function -> cf-demo2-events-pubsub -> Logs

Step-05: Publish Messages in Cloud Pub/Sub Topic¶

Go to Cloud Pub/Sub -> mytopic1 -> MESSAGES -> PUBLISH MESSAGE
Number of Messages: 10
Message Body: My Pub/Message
Click on PUBLISH

Step-05: Review Cloud Function Logs¶

Go to Cloud Function -> cf-demo2-events-pubsub -> Logs