openshift-docs/modules/serverless-sinkbinding-yaml.adoc

// Module included in the following assemblies:
//
// serverless/event_workflows/serverless-sinkbinding.adoc

[id="serverless-sinkbinding-yaml_{context}"]
= Using SinkBinding with the YAML method

This guide describes the steps required to create, manage, and delete a SinkBinding instance using YAML files.

.Prerequisites

* You have Knative Serving and Eventing installed.

[NOTE]
====
The following procedure requires you to create YAML files.

If you change the names of the YAML files from those used in the examples, you must ensure that you also update the corresponding CLI commands.
====

[IMPORTANT]
====
Before developers can use a SinkBinding, cluster administrators must label the namespace that will be configured in the SinkBinding with `bindings.knative.dev/include:"true"`:

[source,terminal]
----
$ oc label namespace <namespace> bindings.knative.dev/include=true
----
====

.Procedure

. To check that SinkBinding is set up correctly, create a Knative event display service, or event sink, that dumps incoming messages to its log.
.. Copy the following sample YAML into a file named `service.yaml`:
+

[source,yaml]
----
apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  name: event-display
spec:
  template:
    spec:
      containers:
        - image: quay.io/openshift-knative/knative-eventing-sources-event-display:latest
----

.. After you have created the `service.yaml` file, apply it by entering:
+

[source,terminal]
----
$ oc apply -f service.yaml
----

. Create a SinkBinding that directs events to the service.
.. Create a file named `sinkbinding.yaml` and copy the following sample code into it:
+

[source,yaml]
----
apiVersion: sources.knative.dev/v1alpha1
kind: SinkBinding
metadata:
  name: bind-heartbeat
spec:
  subject:
    apiVersion: batch/v1
    kind: Job <1>
    selector:
      matchLabels:
        app: heartbeat-cron

  sink:
    ref:
      apiVersion: serving.knative.dev/v1
      kind: Service
      name: event-display
----
<1> In this example, any Job with the label `app: heartbeat-cron` will be bound to the event sink.

.. After you have created the `sinkbinding.yaml` file, apply it by entering:
+

[source,terminal]
----
$ oc apply -f sinkbinding.yaml
----

. Create a CronJob.
.. Create a file named `heartbeats-cronjob.yaml` and copy the following sample code into it:
+

[source,yaml]
----
apiVersion: batch/v1beta1
kind: CronJob
metadata:
  name: heartbeat-cron
spec:
spec:
  # Run every minute
  schedule: "* * * * *"
  jobTemplate:
    metadata:
      labels:
        app: heartbeat-cron
        bindings.knative.dev/include: "true"
    spec:
      template:
        spec:
          restartPolicy: Never
          containers:
            - name: single-heartbeat
              image: quay.io/openshift-knative/knative-eventing-sources-heartbeats:latest
              args:
                - --period=1
              env:
                - name: ONE_SHOT
                  value: "true"
                - name: POD_NAME
                  valueFrom:
                    fieldRef:
                      fieldPath: metadata.name
                - name: POD_NAMESPACE
                  valueFrom:
                    fieldRef:
                      fieldPath: metadata.namespace
----

+
[IMPORTANT]
====
To use SinkBinding, you must manually add a `bindings.knative.dev/include=true` label to your Knative resources.

For example, to add this label to a CronJob instance, add the following lines to the Job resource YAML definition:

[source,yaml]
----
  jobTemplate:
    metadata:
      labels:
        app: heartbeat-cron
        bindings.knative.dev/include: "true"
----

====

+
.. After you have created the `heartbeats-cronjob.yaml` file, apply it by entering:
+

[source,terminal]
----
$ oc apply -f heartbeats-cronjob.yaml
----

. Check that the controller is mapped correctly by entering the following command and inspecting the output:
+

[source,terminal]
----
$ oc get sinkbindings.sources.knative.dev bind-heartbeat -oyaml
----

+
.Example output
[source,yaml]
----
spec:
  sink:
    ref:
      apiVersion: serving.knative.dev/v1
      kind: Service
      name: event-display
      namespace: default
  subject:
    apiVersion: batch/v1
    kind: Job
    namespace: default
    selector:
      matchLabels:
        app: heartbeat-cron
----

.Verification steps

You can verify that the Kubernetes events were sent to the Knative event sink by looking at the message dumper function logs.

. Enter the command:
+

[source,terminal]
----
$ oc get pods
----

. Enter the command:
+

[source,terminal]
----
$ oc logs $(oc get pod -o name | grep event-display) -c user-container
----

+
.Example output

[source,terminal]
----
☁️  cloudevents.Event
Validation: valid
Context Attributes,
  specversion: 1.0
  type: dev.knative.eventing.samples.heartbeat
  source: https://knative.dev/eventing-contrib/cmd/heartbeats/#event-test/mypod
  id: 2b72d7bf-c38f-4a98-a433-608fbcdd2596
  time: 2019-10-18T15:23:20.809775386Z
  contenttype: application/json
Extensions,
  beats: true
  heart: yes
  the: 42
Data,
  {
    "id": 1,
    "label": ""
  }
----