Channels

This fan-out pattern, however, introduces complex problems for the application architecture, such as retries, timeouts, and persistence. Instead of burdening the producer with these problems, you can use channels.

Channels function as event delivery mechanisms that can fan out received events, through subscriptions, to multiple destinations, referred to as sinks. Examples of sinks include brokers and Knative services.

There are several kinds of channels, but they all make it possible to deliver events to all relevant consumers and, importantly, make the events persist.