It is not clear why Eventing optional components are optional

[pierDipi]

Users have been reporting multiple times that their Broker or Channel setup doesn't work because the documentation reports that Broker and Channel layers are optional like in knative/eventing#5944.

Those optional components are required to follow the next steps, so I'm proposing to remove the Optional word in the heading and instead add a sentence explaining why a Broker or Channel layer might be optional and what you can't do without that particular layer.

Expected Behavior

• There is no confusion

Steps to Reproduce the Problem

1. Install required components only
2. Follow the create a Broker page: https://knative.dev/docs/eventing/broker/create-mtbroker/

Additional Info

• https://knative.dev/docs/install/eventing/install-eventing-with-yaml/
• https://knative.dev/docs/install/eventing/install-eventing-with-yaml/#optional-install-a-default-channel-messaging-layer
• https://knative.dev/docs/install/eventing/install-eventing-with-yaml/#optional-install-a-broker-layer

Install information:

• Platform (GKE, IKS, AKS, etc.): All
• Knative Version: All

/kind eventing

[limylily]

It is recommended to modify the document.

Both the Channel layer and the Broker layer need to be installed, but you can choose one of multiple options to install.

Is there a corresponding relationship between multiple options? For example, whether installing NATS Channel for the Channel layer and Apache Kafka Broker for the Broker layer can test successfully?

[pierDipi]

I agree a clarification may be helpful.

Is there a corresponding relationship between multiple options? For example, whether installing NATS Channel for the Channel layer and Apache Kafka Broker for the Broker layer can test successfully?

This is possible, you can use multiple layers in the same cluster.

The only relationship that they have is that they all conform to the shared spec: https://github.com/knative/specs/tree/main/specs/eventing that allows multiple layers to be integrated and communicate with each other in a loosely coupled way.

[github-actions]

This issue is stale because it has been open for 90 days with no
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[pierDipi]

/remove-lifecycle stale