Real Time Updates easy
What is the role of a 'Pub/Sub' (Publish-Subscribe) system in a chat app?
- A It stores the chat logs in the database.
- B It routes a message sent by one user to all other users who are 'listening' to that specific chat room.
- C It authenticates the user.
- D It compresses the images.
Answer: B. It routes a message sent by one user to all other users who are 'listening' to that specific chat room.
Pub/Sub decouples senders from receivers. User A publishes to 'Room 1'. Redis/Kafka ensures that Users B, C, and D (Subscribers of 'Room 1') receive it instantly.
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