Pub/Sub with Cloud Functions integration in GCP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is Google Cloud Pub/Sub?

Google Cloud Pub/Sub is a messaging service that lets applications send and receive messages asynchronously. It helps different parts of a system talk to each other without waiting.

beginner

How does a Cloud Function get triggered by a Pub/Sub message?

A Cloud Function subscribes to a Pub/Sub topic. When a message is published to that topic, the function automatically runs and receives the message data.

beginner

What is the role of a Pub/Sub topic in Cloud Functions integration?

A Pub/Sub topic acts like a mailbox where messages are sent. Cloud Functions listen to this mailbox and react when new messages arrive.

intermediate

Why use Pub/Sub with Cloud Functions instead of calling functions directly?

Using Pub/Sub decouples parts of your system. It allows messages to queue up if the function is busy, making the system more reliable and scalable.

intermediate

What is the format of the message data received by a Cloud Function from Pub/Sub?

The message data is base64-encoded. The function needs to decode it to get the original message content.

What triggers a Cloud Function when using Pub/Sub integration?

A A new message published to a Pub/Sub topic

B A user clicking a button in the UI

C A scheduled timer event

D Manual invocation from the console

Cloud Functions are triggered automatically when a new message is published to the subscribed Pub/Sub topic.

How does Pub/Sub help improve system reliability with Cloud Functions?

A By queuing messages if the function is busy

B By running functions faster

C By storing data permanently

D By encrypting messages automatically

Pub/Sub queues messages so they are not lost if the Cloud Function is busy or temporarily unavailable.

What must you do to the message data in a Cloud Function triggered by Pub/Sub?

A Decode it from base64

B Encrypt it

C Convert it to JSON automatically

D Ignore it

Pub/Sub message data is base64-encoded, so the function must decode it to use the original content.

Which of the following is NOT a benefit of using Pub/Sub with Cloud Functions?

A Decoupling system components

B Automatic scaling of functions

C Direct synchronous calls between services

D Handling bursts of messages smoothly

Pub/Sub enables asynchronous communication, not direct synchronous calls.

What is a Pub/Sub topic?

A A channel where messages are sent and received

B A database for storing messages

C A Cloud Function configuration

D A user account in GCP

A Pub/Sub topic is like a channel or mailbox where messages are published and from which subscribers receive messages.

Explain how Cloud Functions and Pub/Sub work together to process messages.

Think about how messages flow from sender to function.

Describe the benefits of using Pub/Sub with Cloud Functions in a cloud application.

Consider system design and handling load.