Description
There maybe different ways of configuring kafka - keys, groups, and topics - to handle different exchange strategies on some level for performance and other streaming logic requirements.
Exchanges are AMQP 0-9-1 entities where messages are sent. Exchanges take a message and route it into zero or more queues. The routing algorithm used depends on the exchange type and rules called bindings. AMQP 0-9-1 brokers provide four exchange types:
| Exchange type | Default pre-declared names |
|---|---|
| Direct | (Empty string) and amq.direct |
| Fanout | amq.fanout |
| Topic | amq.topic |
| Header | amq.match (and amq.headers in RabbitMQ) |
Besides the exchange type, exchanges are declared with a number of attributes, the most important of which are:
- Durability (exchanges survive broker restart)
- Auto-delete (exchange is deleted when last queue is unbound from it)
- Arguments (optional, used by plugins and broker-specific features)
Exchanges can be durable or transient. Durable exchanges survive broker restart whereas transient exchanges do not (they have to be redeclared when broker comes back online). Not all scenarios and use cases require exchanges to be durable.