Logic to generate default cluster_name if not supplied

[mitali-salvi]

Description of changes:

1. Implement logic to generate a default cluster-name (generated using the release name) if not supplied in Helm chart. This cluster name will be passed down to the cloudwatch-agent and fluent-bit config
2. Marking region as a required field. this region will be passed down to both the CWA and fluent-bit config

Testing
cluster_name is not provided, attaching snippets rather than the entire YAML

CWA --
  image: public.ecr.aws/cloudwatch-agent/cloudwatch-agent:1.300031.1b317
  mode: daemonset
  serviceAccount: cloudwatch-agent
  config: "{\"agent\":{\"region\":\"us-east-1\"},\"logs\":{\"metrics_collected\":{\"app_signals\":{\"hosted_in\":\"k8s-cluster-0ba3ba5\"},\"kubernetes\":{\"cluster_name\":\"k8s-cluster-0ba3ba5\",\"enhanced_container_insights\":true}}},\"traces\":{\"traces_collected\":{\"app_signals\":{}}}}"

FluentBit --
        image: public.ecr.aws/aws-observability/aws-for-fluent-bit:2.31.12.20230911
        imagePullPolicy: Always
        env:
        - name: AWS_REGION
          value: us-east-1
        - name: CLUSTER_NAME
          value: k8s-cluster-0ba3ba5

cluster_name is provided via the helm chart, attaching snippets rather than the entire YAML

helm upgrade --install  --debug --namespace amazon-cloudwatch amazon-cloudwatch-operator ./ --create-namespace --set clusterName=cloudwatchagent-operator --set region=us-east-1


CWA --
  image: public.ecr.aws/cloudwatch-agent/cloudwatch-agent:1.300031.1b317
  mode: daemonset
  serviceAccount: cloudwatch-agent
  config: "{\"logs\":{\"metrics_collected\":{\"app_signals\":{\"hosted_in\":\"k8s-cluster-0ba3ba5\"},\"kubernetes\":{\"cluster_name\":\"k8s-cluster-0ba3ba5\",\"enhanced_container_insights\":true}}},\"traces\":{\"traces_collected\":{\"app_signals\":{}}}}"

FluentBit --
        image: public.ecr.aws/aws-observability/aws-for-fluent-bit:2.31.12.20230911
        imagePullPolicy: Always
        env:
        - name: AWS_REGION
          value: us-east-1
        - name: CLUSTER_NAME
          value: "k8s-cluster-0ba3ba5"

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[sky333999]

Isnt lines 12-16 the same as

{{- default (printf "k8s-cluster-%s" (sha256sum .Release.Name | trunc 7)) .Values.clusterName }}

?

[sky333999]

Using the built in required func, Lines 1-3 can instead be:

{{- $region := .Values.region | required ".Values.region is required." -}}

[sky333999]

@movence doesnt this bring back the bug you fixed for numeric only cluster names not being quoted?

[sky333999]

Whats diff between the two funcs below?
I would have expected a generic helper function that takes a config (either user provided or default) as an input and then just merges region & cluster name on top of that.

.Values.agent.config | injectRegionAndClusterName | toJson | quote
.Values.agent.defaultConfig | injectRegionAndClusterName | toJson | quote

[sky333999]

Can we keep the comments on these saying this is required and the cluster name is optional and we generate one if not provdied

[sky333999]

Is the release name unique enough for our purposes here? Is a hash good enough or do we need randomness?
If the same release is installed on multiple clusters with the same name, wont all the clusters have the same hash?

[movence]

This is a good point, and we should add some randomness to it.