After events have been sent to a channel from an event source or producer, these events can be sent to multiple Knative services, or other sinks, by using a subscription.

Channel workflow overview

If a subscriber rejects an event, there are no re-delivery attempts by default. Developers can configure re-delivery attempts by modifying the delivery spec in a Subscription object.

Creating subscriptions

Developers can create subscriptions that allow event sinks to subscribe to channels and receive events.

Creating subscriptions in the Developer perspective

Prerequisites

To create subscriptions using the Developer perspective, ensure that:

  • The OpenShift Serverless Operator, Knative Serving, and Knative Eventing are installed on your OpenShift Container Platform cluster.

  • You have logged in to the web console.

  • You have created a project or have access to a project with the appropriate roles and permissions to create applications and other workloads in OpenShift Container Platform.

  • You have created an event sink, such as a Knative service, and a channel.

Procedure
  1. In the Developer perspective, navigate to the Topology page.

  2. Create a subscription using one of the following methods:

    1. Hover over the channel that you want to create a subscription for, and drag the arrow. The Add Subscription option is displayed.

      Create a subscription for the channel
      1. Select your sink as a subscriber from the drop-down list.

      2. Click Add.

    2. If the service is available in the Topology view under the same namespace or project as the channel, click on the channel that you want to create a subscription for, and drag the arrow directly to a service to immediately create a subscription from the channel to that service.

Verification
  • After the subscription has been created, you can see it represented as a line that connects the channel to the service in the Topology view: