Chart: Add securityContext parameter to prometheus deployment

Signed-off-by: Andy Librian <andylibrian@gmail.com>

charts/flagger/templates/prometheus.yaml

@@ -255,6 +255,10 @@ spec:
               mountPath: /etc/prometheus
             - name: data-volume
               mountPath: /prometheus/data
+          {{- if .Values.prometheus.securityContext.enabled }}
+          securityContext:
+{{ toYaml .Values.prometheus.securityContext.context | indent 12 }}
+          {{- end }}
       {{- if .Values.prometheus.pullSecret }}
       imagePullSecrets:
         - name: {{ .Values.prometheus.pullSecret }}

charts/flagger/values.yaml

@@ -127,6 +127,12 @@ prometheus:
   image: docker.io/prom/prometheus:v2.23.0
   pullSecret:
   retention: 2h
+  # when enabled, it will add a security context for the prometheus pod
+  securityContext:
+    enabled: false
+    context:
+      readOnlyRootFilesystem: true
+      runAsUser: 10001
 
 kubeconfigQPS: ""
 kubeconfigBurst: ""