[opentelemetry-operator] allow for overriding namespace in values file

[CharlieTLe]

The operator helm chart only uses the .Release.Namespace. When the helm chart is used as a sub chart, it's not possible to deploy it in a separate namespace.

We should be able to do something like

{{/*
Allow the release namespace to be overridden
*/}}
{{- define "opentelemetry-operator.namespace" -}}
  {{- if .Values.namespaceOverride -}}
    {{- .Values.namespaceOverride -}}
  {{- else -}}
    {{- .Release.Namespace -}}
  {{- end -}}
{{- end -}}

and then override it in the values file like

# Top level field indicating an override for the namespace
namespaceOverride: "opentelemetry-operator-system"

[TylerHelmuth]

When the helm chart is used as a sub chart, it's not possible to deploy it in a separate namespace.

Is that typical? We normally follow other popular chart's patterns whenever we can, do you have examples of other charts supporting this?

[CharlieTLe]

Yes, here's it being done in the opentelemetry-kube-stack chart:

opentelemetry-helm-charts/charts/opentelemetry-kube-stack/templates/_helpers.tpl

Lines 34 to 43 in 3f84c9b

	{{/*
	Allow the release namespace to be overridden
	*/}}
	{{- define "opentelemetry-kube-stack.namespace" -}}
	{{- if .Values.namespaceOverride -}}
	{{- .Values.namespaceOverride -}}
	{{- else -}}
	{{- .Release.Namespace -}}
	{{- end -}}
	{{- end -}}

opentelemetry-helm-charts/charts/opentelemetry-kube-stack/values.yaml

Lines 3 to 4 in 3f84c9b

	# Top level field indicating an override for the namespace
	namespaceOverride: ""

[TylerHelmuth]

Oh I misunderstood what you were asking for. Yes we can add a namespaceoverride option. Our collector chart has that as well