feat: Add customised env var and feature flags

This change adds 3 new features:
 - The ability to enable feature flags with the .Values.features key
 - The ability to add extra environment variables to the container env
 - The ability to completely override env variables (not recommended)

Closes CrunchyData#262

Author: jaitaiwan

helm/install/templates/_helpers.tpl

@@ -98,3 +98,37 @@ imagePullSecrets:
   value: {{ $object.image | quote }}
 {{- end }}
 {{- end }}
+
+
+{{- define "install.defaultEnv" -}}
+- name: CRUNCHY_DEBUG
+  value: {{ .Values.debug | ne false | quote }}
+- name: PGO_NAMESPACE
+  valueFrom: { fieldRef: { apiVersion: v1, fieldPath: metadata.namespace } }
+{{- if .Values.singleNamespace }}
+- name: PGO_TARGET_NAMESPACE
+  valueFrom: { fieldRef: { apiVersion: v1, fieldPath: metadata.namespace } }
+{{- end }}
+{{- if .Values.workers }}
+- name: PGO_WORKERS
+  value: {{ .Values.workers | quote }}
+{{- end }}
+{{- include "install.relatedImages" . }}
+{{- if .Values.disable_check_for_upgrades }}
+- name: CHECK_FOR_UPGRADES
+  value: "false"
+{{- end }}
+{{- if .Values.features }}
+{{- $value := .Values.features }}
+- name: PGO_FEATURE_GATES
+{{- $out := "" -}}
+{{- if eq (kindOf $value) "map" -}}
+{{- range $key, $val := $value -}}
+  {{- $out = (print $out $key "=" $val ",") -}}
+{{- end }}
+{{- end }}
+  value: "{{ trimSuffix "," $out }}"
+{{- end }}
+{{- end }}{{/* define */}}
+
+

helm/install/templates/manager.yaml

@@ -24,22 +24,13 @@ spec:
       - name: operator
         image: {{ required ".Values.controllerImages.cluster is required" .Values.controllerImages.cluster | quote }}
         env:
-        - name: CRUNCHY_DEBUG
-          value: {{ .Values.debug | ne false | quote }}
-        - name: PGO_NAMESPACE
-          valueFrom: { fieldRef: { apiVersion: v1, fieldPath: metadata.namespace } }
-        {{- if .Values.singleNamespace }}
-        - name: PGO_TARGET_NAMESPACE
-          valueFrom: { fieldRef: { apiVersion: v1, fieldPath: metadata.namespace } }
+        {{- if .Values.envOverride }}
+        {{- toYaml .Values.envOverride | nindent 10 }}
+        {{- else -}}
+        {{- include "install.defaultEnv" . | nindent 10 }}
         {{- end }}
-        {{- if .Values.workers }}
-        - name: PGO_WORKERS
-          value: {{ .Values.workers | quote }}
-        {{- end }}
-        {{- include "install.relatedImages" . | indent 8 }}
-        {{- if .Values.disable_check_for_upgrades }}
-        - name: CHECK_FOR_UPGRADES
-          value: "false"
+        {{- if .Values.extraEnv }}
+        {{- toYaml .Values.extraEnv | nindent 10 }}
         {{- end }}
         {{- if .Values.resources.controller }}
         resources:

helm/install/values.yaml

@@ -49,3 +49,29 @@ resources:
 # postgres-operator.crunchydata.com, will cause an error
 # customPodLabels:
 #  example.com: custom-label
+
+# Enable feature gates for PGO, by explicitly seting the value for the flags
+# features:
+#   AutoGrowVolumes: true
+#   Feature2: false
+#   Feature3: somevalue
+
+# Define extra environment variables for the chart, which will get added to the container's env
+# extraEnv:
+#   - name: MY_VAR
+#     value: "myvalue"
+#   - name: MY_CONFIGMAP_VAR
+#     valueFrom:
+#       configMapKeyRef:
+#         name: s3-settings
+#         key: bucket
+#   - name: MY_SECRET_VAR
+#     valueFrom:
+#       secretKeyRef:
+#         name: s3-secret
+#         key: key
+
+# Override environment variables entirely !!DANGEROUS!!
+# envOverride:
+#   - name: PG_DEBUG
+#     value: "true"