Lesson 03.8
Queues vs pub/sub, partition keys, slow consumers
A queue gives each message to one consumer, pub/sub gives every subscriber its own copy, and a partition key decides which messages stay in order together.
Messages in two tubes
Every taxi ride sends four messages: asked, accepted, picked up, finished. They travel to the office down two tubes, and each tube delivers its messages in order. Ava works out the fares; Ben keeps the big map up to date. Each gets a copy of every message.
Which tube should each message go down?
In this lesson you'll
- 1Watch messages sorted by ride.
- 2Guess what happens when they're sorted by type.
- 3Keep each ride in order even when a tube is busy.