Redis Lists (supports Redis Cluster) Click here for latest

Redis Lists scaler with support for Redis Cluster topology

Availability: v2.1+ Maintainer: Community

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Trigger Specification

This specification describes the redis-cluster trigger that scales based on the length of a list in a Redis Cluster.

triggers:
- type: redis-cluster
  metadata:
    addresses: localhost:6379 # Comma separated list of the format host:port
    passwordFromEnv: REDIS_PASSWORD
    listName: mylist # Required
    listLength: "5" # Required
    enableTLS: "false" # optional
    # Alternatively, you can use existing environment variables to read configuration from:
    # See details in "Parameter list" section
    addressesFromEnv: REDIS_ADDRESSES # Optional. You can use this instead of `addresses` parameter

Parameter list:

  • addresses - Comma separated list of hosts and ports of the Redis Cluster nodes.
  • hosts - Comma separated list of hosts of the Redis Cluster nodes. Alternative to addresses and requires ports to be configured as well.
  • ports - Comma separated list of corresponding ports for the hosts of the Redis Cluster nodes. Alternative to addresses and requires hosts to be configured as well.
  • passwordFromEnv - Environment variable to read the authentication password from to authenticate with the Redis server.
    • Both the hostname and password fields need to be set to the names of the environment variables in the target deployment that contain the host name and password respectively.
  • listName - Name of the Redis List that you want to monitor.
  • listLength - Average target value to trigger scaling actions.
  • enableTLS - Allow a connection to a redis queue using tls. (Values: true, false, Default: false, Optional)

⚠️ WARNING: In this version, enableTLS: true automatically skips the certificate verification which is insecure. Use v2.9 or above to properly verify the server certificate.

Some parameters could be provided using environmental variables, instead of setting them directly in metadata. Here is a list of parameters you can use to retrieve values from environment variables:

  • addressesFromEnv - The hosts and their respective ports of the Redis Cluster nodes, similar to addresses, but reads it from an environment variable on the scale target.
  • hostsFromEnv - The hosts of the Redis Cluster nodes, similar to hosts, but reads it from an environment variable on the scale target.
  • portsFromEnv - The corresponding ports for the hosts of the Redis Cluster nodes, similar to ports, but reads it from an environment variable on the scale target.

Authentication Parameters

You can authenticate by using a password.

Connection Authentication:

  • addresses - Comma separated list of host:port format.
  • hosts - Comma separated list of hostname of the Redis Cluster nodes. If specified, the ports should also be specified.
  • ports - Comma separated list of ports of the Redis Cluster nodes. If specified, the hosts should also be specified.

Password Authentication:

  • password - Redis password to authenticate with.

Example

Here is an example of how to deploy a scaled object with the redis-cluster scale trigger which uses TriggerAuthentication.

You can also provide the passwordFromEnv on the ScaledObject directly.

apiVersion: v1
kind: Secret
metadata:
  name: votes-db-secret
  namespace: my-project
type: Opaque
data:
  redis_password: YWRtaW4=
---
apiVersion: keda.sh/v1alpha1
kind: TriggerAuthentication
metadata:
  name: keda-trigger-auth-redis-secret
  namespace: my-project
spec:
  secretTargetRef:
  - parameter: password
    name: votes-db-secret
    key: redis_password
---
apiVersion: keda.sh/v1alpha1
kind: ScaledObject
metadata:
  name: redis-scaledobject
  namespace: my-project
spec:
  scaleTargetRef:
    name: votes
  triggers:
  - type: redis-cluster
    metadata:
      addresses: node1:6379, node2:6379, node3:6379
      listName: mylist
      listLength: "10"
    authenticationRef:
      name: keda-trigger-auth-redis-secret