Creating your first Trigger
Creating your first Trigger¶
kn trigger create cloudevents-trigger --sink cloudevents-player --broker example-broker
Trigger 'cloudevents-trigger' successfully created in namespace 'default'.
apiVersion: eventing.knative.dev/v1 kind: Trigger metadata: name: cloudevents-trigger annotations: knative-eventing-injection: enabled spec: broker: example-broker subscriber: ref: apiVersion: serving.knative.dev/v1 kind: Service name: cloudevents-player
After you've created your YAML file, named something like
ce-trigger.yaml, apply it by running the command:
kubectl apply -f ce-trigger.yaml
What CloudEvents is my Trigger listening for?
Because we didn't specify a
--filter in our
kn command, the Trigger is listening for any CloudEvents coming into the Broker.
An example on how to use Filters is provided below.
Now, when we go back to the CloudEvents Player and send an Event, we see that CloudEvents are both sent and received by the CloudEvents Player:
What if I want to filter on CloudEvent attributes?
First, delete your existing Trigger:
kn trigger delete cloudevents-player
kn trigger create cloudevents-player-filter --sink cloudevents-player --broker example-broker --filter type=some-type
If you send a CloudEvent with type "some-type," it is reflected in the CloudEvents Player UI. The Trigger ignores any other types.
You can filter on any aspect of the CloudEvent you would like to.
Some people call this "Event-Driven Architecture" which can be used to create your own "Functions as a Service" on Kubernetes