Pub/sub vs streams comparison in Redis - Hands-On Comparison

Understanding Pub/Sub and Streams in Redis

📖 Scenario: You are building a simple notification system using Redis. You want to learn how to use Redis Pub/Sub and Streams to send and receive messages.

🎯 Goal: Build two small Redis data structures: one using Pub/Sub channels and one using Streams. Learn how to publish messages and read them using both methods.

📋 What You'll Learn

Create a Pub/Sub channel named notifications

Publish a message 'Hello Pub/Sub!' to the notifications channel

Create a Stream named mystream

Add a message with field message and value 'Hello Streams!' to mystream

💡 Why This Matters

🌍 Real World

Redis Pub/Sub is great for real-time notifications like chat messages or live updates. Streams are useful for event sourcing, logging, and reliable message processing.

💼 Career

Understanding Redis Pub/Sub and Streams is valuable for backend developers working on scalable, real-time applications and data pipelines.

1

Create a Pub/Sub channel and publish a message

Use the Redis command PUBLISH to send the message 'Hello Pub/Sub!' to the channel named notifications.

Redis

# Use PUBLISH notifications 'Hello Pub/Sub!'
# Your code here

Need a hint?

Use the PUBLISH command followed by the channel name and the message in single quotes.

2

Create a Stream and add a message

Use the Redis command XADD to add a message to the Stream named mystream. The message should have the field message with the value 'Hello Streams!'. Use * for the ID to let Redis generate it.

Redis

PUBLISH notifications 'Hello Pub/Sub!'
# Use XADD mystream * message 'Hello Streams!'
# Your code here

Need a hint?

The XADD command adds entries to a stream. Use * to auto-generate the ID.

3

Subscribe to the Pub/Sub channel

Use the Redis command SUBSCRIBE to listen to messages on the channel named notifications.

Redis

PUBLISH notifications 'Hello Pub/Sub!'
XADD mystream * message 'Hello Streams!'
# Use SUBSCRIBE notifications
# Your code here

Need a hint?

The SUBSCRIBE command listens for messages on a channel.

4

Read messages from the Stream

Use the Redis command XREAD to read new messages from the Stream named mystream. Use STREAMS mystream 0 to read all messages from the beginning.

Redis

PUBLISH notifications 'Hello Pub/Sub!'
XADD mystream * message 'Hello Streams!'
SUBSCRIBE notifications
# Use XREAD STREAMS mystream 0
# Your code here

Need a hint?

The XREAD command reads messages from streams. Use 0 to read from the start.