Improve ray-cluster.external-redis.yaml

[Yicheng-Lu-llll]

Why are these changes needed?

The Kuberay pull request #950 discusses using Redis password secrets as environment variables, as described in the Kubernetes documentation.

Specifically, a new environment variable RAY_REDIS_PASSWORD is created and assigned a value from a secret:

 - name: RAY_REDIS_PASSWORD
            valueFrom:
              secretKeyRef:
                name: redis-password-secret
                key: password

Additionally, the rayStartParams configuration includes a reference to this environment variable:

rayStartParams:
   redis-password: $REDIS_PASSWORD

However, the current Kuberay implementation sets another environment variable, REDIS_PASSWORD based on rayStartParams["redis-password"] if the user does not define it.

	if !envVarExists(REDIS_PASSWORD, container.Env) {
		// setting the REDIS_PASSWORD env var from the params
		port := v1.EnvVar{Name: REDIS_PASSWORD}
		if value, ok := rayStartParams["redis-password"]; ok {
			port.Value = value
		}
		container.Env = append(container.Env, port)
	}

This leads to issues:

• As shown below, the REDIS_PASSWORD environment variable is redundant, as it only points to the RAY_REDIS_PASSWORD environment variable.

    Environment:
      RAY_REDIS_ADDRESS:               redis:6379
      RAY_REDIS_PASSWORD:              <set to the key 'password' in secret 'redis-password-secret'>  Optional: false
      RAY_CLUSTER_NAME:                 (v1:metadata.labels['ray.io/cluster'])
      RAY_PORT:                        6379
      RAY_ADDRESS:                     127.0.0.1:6379
      RAY_USAGE_STATS_KUBERAY_IN_USE:  1
      REDIS_PASSWORD:                  $RAY_REDIS_PASSWORD
      RAY_external_storage_namespace:  my-raycluster-storage-namespace

To resolve this, it is advisable to set RAY_REDIS_PASSWORD as REDIS_PASSWORD in the ray-cluster.external-redis.yaml to eliminate duplicate environment variables.

Related issue number

Checks

kubectl apply -f kuberay/ray-operator/config/samples/ray-cluster.external-redis.yaml
kubectl describe  $(kubectl get pods -o=name | grep head)

    Environment:
      RAY_REDIS_ADDRESS:               redis:6379
      REDIS_PASSWORD:                  <set to the key 'password' in secret 'redis-password-secret'>  Optional: false
      RAY_CLUSTER_NAME:                 (v1:metadata.labels['ray.io/cluster'])
      RAY_PORT:                        6379
      RAY_ADDRESS:                     127.0.0.1:6379
      RAY_USAGE_STATS_KUBERAY_IN_USE:  1
      RAY_external_storage_namespace:  my-raycluster-storage-namespace

• I've made sure the tests are passing.
• Testing Strategy
  • Unit tests
  • Manual tests
  • This PR is not tested :(

[kevin85421]

LGTM. The YAML file is included in the CI's config test.