Stream Events to the Flux Notification Controller

component-operator can emit reconciliation events — successful applies, errors, state transitions — to the Flux notification controller, which then forwards them to any configured alert provider (Slack, Microsoft Teams, PagerDuty, a generic webhook, etc.).

This tutorial wires component-operator events to a smee.io channel so you can observe them in real time in your browser.

Prerequisites

You need a Kubernetes cluster with Flux source-controller and component-operator installed. If you don’t have one yet, follow the Cluster Setup guide.

Install the Flux notification controller

The notification controller is not installed by the minimal flux install --components source-controller command used in the getting-started guide. Install it now:

flux install --components notification-controller

This adds the controller and its CRDs (Alert, Provider, Receiver) to the cluster.

1. Reconfigure component-operator to stream events

Pass the --events-address flag by reinstalling the Helm chart:

helm upgrade --install component-operator \
  oci://ghcr.io/sap/component-operator/charts/component-operator \
  --namespace flux-system \
  --set options.eventsAddress=http://notification-controller

The short hostname notification-controller resolves to the notification controller service inside the flux-system namespace. If component-operator runs in a different namespace, use the fully qualified name instead:

http://notification-controller.flux-system.svc.cluster.local/

In that case you may also need to extend the network policies in flux-system to allow inbound traffic from the component-operator namespace.

2. Patch the Alert CRD

Flux’s Alert CRD does not list Component as an allowed event source kind out of the box. Add it with a JSON Patch:

kubectl patch crd alerts.notification.toolkit.fluxcd.io \
  --type json \
  -p '[{"op":"add","path":"/spec/versions/0/schema/openAPIV3Schema/properties/spec/properties/eventSources/items/properties/kind/enum/-","value":"Component"}]'

Note: If your Flux installation has a CRD with multiple versions, repeat the patch for each version entry (changing versions/0 to versions/1, etc.). See Notifications for details.

3. Create a smee.io channel

smee.io is a free webhook relay — events posted to your channel URL are displayed in the browser in real time.

1. Open https://smee.io and click Start a new channel.
2. Copy the channel URL shown on the page (it looks like https://smee.io/aBcDeFgHiJkLmNoP).

Keep the smee.io page open in your browser — you will see events arrive here later.

4. Create the Flux Provider and Alert

Replace <your-channel> with the URL you copied.

# smee-provider.yaml
---
apiVersion: notification.toolkit.fluxcd.io/v1beta3
kind: Provider
metadata:
  name: smee
  namespace: default
spec:
  type: generic
  address: https://smee.io/<your-channel>

kubectl apply -f smee-provider.yaml

# component-alert.yaml
---
apiVersion: notification.toolkit.fluxcd.io/v1beta3
kind: Alert
metadata:
  name: component
  namespace: default
spec:
  providerRef:
    name: smee
  eventSources:
    - kind: Component
      name: '*'
      namespace: default
  eventSeverity: info

kubectl apply -f component-alert.yaml

5. Deploy podinfo and observe events

Follow Scenario 2: Kustomize to deploy podinfo from its Git repository. Create the source and component:

# podinfo-git-source.yaml
---
apiVersion: source.toolkit.fluxcd.io/v1
kind: GitRepository
metadata:
  name: podinfo
  namespace: default
spec:
  interval: 5m
  url: https://github.com/stefanprodan/podinfo
  ref:
    branch: master

kubectl apply -f podinfo-git-source.yaml

# podinfo-kustomize.yaml
---
apiVersion: core.cs.sap.com/v1alpha1
kind: Component
metadata:
  name: podinfo
  namespace: default
spec:
  sourceRef:
    fluxGitRepository:
      name: podinfo
  path: kustomize

kubectl apply -f podinfo-kustomize.yaml

Switch to your browser and watch the smee.io channel. As component-operator reconciles the podinfo component you should see a stream of events appear, each carrying:

• The component name and namespace
• The reconciliation state (Progressing, Ready, etc.)
• A human-readable message describing what happened

Once the component is Ready:

kubectl get component podinfo

Try triggering more events by suspending and resuming the component:

kubectl patch component podinfo --type merge -p '{"spec":{"suspend":true}}'
kubectl patch component podinfo --type merge -p '{"spec":{"suspend":false}}'

Each state change produces a new event in the smee.io channel.

6. Cleanup

Delete the podinfo resources:

kubectl delete component podinfo
kubectl delete gitrepository podinfo

Delete the notification objects:

kubectl delete alert component -n default
kubectl delete provider smee -n default

Restore component-operator to its default configuration (no event streaming):

helm upgrade --install component-operator \
  oci://ghcr.io/sap/component-operator/charts/component-operator \
  --namespace flux-system \
  --set options.eventsAddress=