Getting started¶
Prerequisites¶
Before you can create an API server source, you must install Knative Eventing and the kubectl
CLI tool.
Create an API server source¶
-
Optional: Create a namespace for the API server source instance:
where; -kubectl create namespace <namespace>
<namespace>
is the name of the namespace that you want to create.Creating a namespace for your API server source and related components allows you to view changes and events for this workflow more easily, since these are isolated from the many other components that may exist in your
default
namespace.It also makes removing the source easier, since you can simply delete the namespace to remove all of the resources.
-
Create a service account:
where; -kubectl create -f - <<EOF apiVersion: v1 kind: ServiceAccount metadata: name: <service-account> namespace: <namespace> EOF
<service-account>
is the name of the service account that you want to create. -<namespace>
is the namespace that you created in step 1 above. -
Create a cluster role:
where; -kubectl create -f - <<EOF apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRole metadata: name: <cluster-role> rules: - apiGroups: - "" resources: - events verbs: - get - list - watch EOF
<cluster-role>
is the name of the cluster role that you want to create. -
Create a cluster role binding:
where; -kubectl create -f - <<EOF apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRoleBinding metadata: name: <cluster-role-binding> roleRef: apiGroup: rbac.authorization.k8s.io kind: ClusterRole name: <cluster-role> subjects: - kind: ServiceAccount name: <service-account> namespace: <namespace> EOF
<cluster-role-binding>
is the name of the cluster role binding that you want to create. -<cluster-role>
is the name of the cluster role that you created in step 3 above. -<service-account>
is the name of the service account that you created in step 2 above. -<namespace>
is the name of the namespace that you created in step 1 above. -
Create an ApiServerSource object:
kubectl create -f - <<EOF
apiVersion: sources.knative.dev/v1
kind: ApiServerSource
metadata:
name: <apiserversource>
namespace: <namespace>
spec:
serviceAccountName: <service-account>
mode: Resource
resources:
- apiVersion: v1
kind: Event
sink:
ref:
apiVersion: v1
kind: Service
name: <sink>
EOF
<apiserversource>
is the name of the source that you want to create.
- <namespace>
is the name of the namespace that you created in step 1 above.
- <service-account>
is the name of the service account that you created in step 2 above.
- <sink>
is the name of the Knative service that you want to use as a sink. A service is used here as an example, however you can use any supported PodSpecable object by updating the kind
from Service
to another object type.
kn source apiserver create <apiserversource> \
--namespace <namespace> \
--mode "Resource" \
--resource "Event:v1" \
--service-account <service-account> \
--sink <sink>
<apiserversource>
is the name of the source that you want to create.
- <namespace>
is the name of the namespace that you created in step 1 above.
- <service-account>
is the name of the service account that you created in step 2 above.
- <sink>
is the name of the PodSpecable object that you want to use as a sink.
-
Create events by launching a test pod in your namespace:
where; -kubectl run busybox --image=busybox --namespace=<namespace> --restart=Never -- ls
<namespace>
is the name of the namespace that you created in step 1 above. -
Delete the test pod:
where; -kubectl --namespace=<namespace> delete pod busybox
<namespace>
is the name of the namespace that you created in step 1 above. -
View the logs to verify that Kubernetes events were sent to the Knative Eventing system:
where; -kubectl logs --namespace=<namespace> -l app=<sink> --tail=100
<namespace>
is the name of the namespace that you created in step 1 above. -<sink>
is the name of the PodSpecable object that you used as a sink in step 5 above.Example log output:
☁️ cloudevents.Event Validation: valid Context Attributes, specversion: 1.0 type: dev.knative.apiserver.resource.update source: https://10.96.0.1:443 subject: /apis/v1/namespaces/apiserversource-example/events/testevents.15dd3050eb1e6f50 id: e0447eb7-36b5-443b-9d37-faf4fe5c62f0 time: 2020-07-28T19:14:54.719501054Z datacontenttype: application/json Extensions, kind: Event name: busybox.1626008649e617e3 namespace: apiserversource-example Data, { "apiVersion": "v1", "count": 1, "eventTime": null, "firstTimestamp": "2020-07-28T19:14:54Z", "involvedObject": { "apiVersion": "v1", "fieldPath": "spec.containers{busybox}", "kind": "Pod", "name": "busybox", "namespace": "apiserversource-example", "resourceVersion": "28987493", "uid": "1efb342a-737b-11e9-a6c5-42010a8a00ed" }, "kind": "Event", "lastTimestamp": "2020-07-28T19:14:54Z", "message": "Started container", "metadata": { "creationTimestamp": "2020-07-28T19:14:54Z", "name": "busybox.1626008649e617e3", "namespace": "default", "resourceVersion": "506088", "selfLink": "/api/v1/namespaces/apiserversource-example/events/busybox.1626008649e617e3", "uid": "2005af47-737b-11e9-a6c5-42010a8a00ed" }, "reason": "Started", "reportingComponent": "", "reportingInstance": "", "source": { "component": "kubelet", "host": "gke-knative-auto-cluster-default-pool-23c23c4f-xdj0" }, "type": "Normal" }
Delete the API server source¶
Deleting the namespace removes the API server source and all of the related resources that were created in this namespace:
kubectl delete namespace <namespace>
<namespace>
is the name of the namespace that you created in step 1 above.