[BUG] Duplicate image and serviceName variables in opensearch-cluster v3.0.0 helm chart

[rajeshm90]

What is the bug?

Getting below error while deploying opensearch-cluster with v3.0.0 helm chart.

error while running post render on files: map[string]interface {}(nil): yaml: unmarshal errors:
        line 70: mapping key "image" already defined at line 36
        line 97: mapping key "image" already defined at line 77
        line 98: mapping key "serviceName" already defined at line 92

How can one reproduce the bug?

We can reproduce by running helm template for v3.0.0 too.

• Download the helm chart from v3.0.0
• run helm template test . and it returns below

  general:
    serviceName: ""
    image: docker.io/opensearchproject/opensearch
    serviceName: test
    image: docker.io/opensearchproject/opensearch:2.3.0

  dashboards:
    image: docker.io/opensearchproject/opensearch-dashboards
    image: docker.io/opensearchproject/opensearch-dashboards:2.3.0

What is the expected behavior?

There shouldn't be any duplicate for the keys under any.

What is your host/environment?

Kubernetes - v1.27.11 (same error on latest versions too)
CONTAINER-RUNTIME - containerd://1.6.23
OS - Talos v1.5.3
Kernel - 6.1.54-talos
Helm Version - v3.15.2

Do you have any screenshots?

Do you have any additional context?

The issue is from the template definition.

• in values.yaml, image and serviceName are defined under dashboards and general sections. Here both are defined without any versions.

cluster:
  general:
    image: docker.io/opensearchproject/opensearch
    serviceName: ""
  dashboards:
    image: docker.io/opensearchproject/opensearch-dashboards

• in template cluster.yaml, reading all under dashboards & general section, and additionally image is defined with version.

  {{- with .Values.cluster.dashboards }}
  dashboards:
    {{- . | toYaml | nindent 4 }}
    image: {{ .image }}:{{ .version }}
  {{- end }}

  {{- with .Values.cluster.general }}
  general:
    {{- . | toYaml | nindent 4 }}
    image: {{ .image }}:{{ .version }}
    serviceName: {{ .serviceName | default $clusterName }}
  {{- end }}

So, dashboards and general returns two image & serviceName variables!!

[prudhvigodithi]

[Triage]
Thanks for the PR #940 @rajeshm90. Will take a look at it.
Adding @swoehrl-mw