RabbitMQ Queue

Scale applications based on RabbitMQ Queue.

Availability: v1.0+ Maintainer: Microsoft

Trigger Specification

This specification describes the rabbitmq trigger for RabbitMQ Queue.

triggers:
- type: rabbitmq
  metadata:
    host: RabbitMqHost # Optional. If not specified, it must be done by using TriggerAuthentication.
    queueLength: '20' # Optional. Queue length target for HPA. Default: 20 messages
    queueName: testqueue
    includeUnacked: 'true' # Optional, use unacked + ready messages count
    apiHost: RabbitApiHost # Optional. Represents the HTTP management API endpoint. If not specified, it must be done by using TriggerAuthentication.
  authenticationRef:
    name: keda-trigger-auth-rabbitmq-conn

Parameter list:

host - Value is the name of the environment variable your deployment uses to get the connection string. This is usually resolved from a Secret V1 or a ConfigMap V1 collections. env and envFrom are both supported. The resolved host should follow a format like amqp://guest:password@localhost:5672/vhost.
queueName - Name of the queue to read message from.
queueLength - Queue length target for HPA. (Default: 20, Optional)
includeUnacked - By default includeUnacked is false in this case scaler uses AMQP protocol, requires host and only counts messages in the queue and ignores unacked messages. If includeUnacked is true then host is not required but apiHost is required in this case scaler uses HTTP management API and counts messages in the queue + unacked messages count. host or apiHost value comes from authentication trigger. (Optional)
apiHost - It has similar format as of host but for HTTP API endpoint, like https://guest:password@localhost:443/vhostname.

Note host and apiHost both have an optional vhost name after the host slash which will be used to scope API request.

Authentication Parameters

TriggerAuthentication CRD is used to connect and authenticate to RabbitMQ:

host - AMQP URI connection string, like amqp://guest:password@localhost:5672/vhost.
apiHost - HTTP API endpoint, like https://guest:password@localhost:443/vhostname.

Example

AMQP protocol:

apiVersion: v1
kind: Secret
metadata:
  name: keda-rabbitmq-secret
data:
  host: <AMQP URI connection string> # base64 encoded value of format amqp://guest:password@localhost:5672/vhost
---
apiVersion: keda.k8s.io/v1alpha1
kind: TriggerAuthentication
metadata:
  name: keda-trigger-auth-rabbitmq-conn
  namespace: default
spec:
  secretTargetRef:
    - parameter: host
      name: keda-rabbitmq-secret
      key: host
---
apiVersion: keda.k8s.io/v1alpha1
kind: ScaledObject
metadata:
  name: rabbitmq-scaledobject
  namespace: default
spec:
  scaleTargetRef:
    deploymentName: rabbitmq-deployment
  triggers:
  - type: rabbitmq
    metadata:
      queueName: testqueue
      queueLength: "20"
    authenticationRef:
      name: keda-trigger-auth-rabbitmq-conn

HTTP protocol:

apiVersion: v1
kind: Secret
metadata:
  name: keda-rabbitmq-secret
data:
  apiHost: <HTTP API endpoint> # base64 encoded value of format https://guest:password@localhost:443/vhostname
---
apiVersion: keda.k8s.io/v1alpha1
kind: TriggerAuthentication
metadata:
  name: keda-trigger-auth-rabbitmq-conn
  namespace: default
spec:
  secretTargetRef:
    - parameter: apiHost
      name: keda-rabbitmq-secret
      key: apiHost
---
apiVersion: keda.k8s.io/v1alpha1
kind: ScaledObject
metadata:
  name: rabbitmq-scaledobject
  namespace: default
spec:
  scaleTargetRef:
    deploymentName: rabbitmq-deployment
  triggers:
  - type: rabbitmq
    metadata:
      includeUnacked: "true"
      queueName: testqueue
      queueLength: "20"
    authenticationRef:
      name: rabbitmq-consumer-trigger