Apache Pulsar

Scale applications based on an Apache Pulsar topic subscription.

Availability: v2.8 Maintainer: Community

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Trigger Specification

This specification describes the pulsar trigger for an Apache Pulsar topic.

triggers:
- type: pulsar
  metadata:
    adminURL: http://localhost:80
    topic: persistent://public/default/my-topic
    subscription: sub1
    msgBacklogThreshold: '5'
    activationMsgBacklogThreshold: '2'

Parameter list:

adminURL - Stats URL of the admin API for your topic.
topic - Pulsar topic. format of persistent://{tenant}/{namespace}/{topicName}
subscription - Name of the topic subscription
msgBacklogThreshold - Average target value to trigger scaling actions. (default: 10)
activationMsgBacklogThreshold - Target value for activating the scaler. Learn more about activation here. (Default: 0, Optional)

Authentication Parameters

If TLS is required you should set tls to enable. If required for your Pulsar configuration, you may also provide a ca, cert and key. ca, cert and key must be specified together.

TLS:

tls: Optional. To enable SSL auth for Pulsar, set this to enable. If not set, TLS for Pulsar is not used, Your shoule set this key to trigger metadata.
ca: Certificate authority file for TLS client authentication.
cert: Certificate for client authentication.
key: Key for client authentication.

Example

Your pulsar cluster no TLS auth:

apiVersion: keda.sh/v1alpha1
kind: ScaledObject
metadata:
  name: pulsar-scaledobject
  namespace: default
spec:
  scaleTargetRef:
    name: pulsar-consumer
  pollingInterval: 30
  triggers:
  - type: pulsar
    metadata:
      adminURL: http://localhost:80
      topic: persistent://public/default/my-topic
      subscription: sub1
      msgBacklogThreshold: '5'

Your pulsar cluster turn on TLS auth:

apiVersion: v1
kind: Secret
metadata:
  name: keda-pulsar-secrets
  namespace: default
data:
  ca: <your ca>
  cert: <your cert>
  key: <your key>
---
apiVersion: keda.sh/v1alpha1
kind: TriggerAuthentication
metadata:
  name: keda-trigger-auth-pulsar-credential
  namespace: default
spec:
  secretTargetRef:
  - parameter: ca
    name: keda-pulsar-secrets
    key: ca
  - parameter: cert
    name: keda-pulsar-secrets
    key: cert
  - parameter: key
    name: keda-pulsar-secrets
    key: key
---
apiVersion: keda.sh/v1alpha1
kind: ScaledObject
metadata:
  name: pulsar-scaledobject
  namespace: default
spec:
  scaleTargetRef:
    name: pulsar-consumer
  pollingInterval: 30
  triggers:
  - type: pulsar
    metadata:
      tls: "enable"
      adminURL: https://localhost:8443
      topic: persistent://public/default/my-topic
      subscription: sub1
      msgBacklogThreshold: '5'
    authenticationRef:
      name:  keda-trigger-auth-pulsar-credential