Omit service account generation when not using strimzi (#53)

README.md

@@ -149,6 +149,17 @@ helm install https://github.com/lightbend/kafka-lag-exporter/releases/download/v
   --set clusters\[0\].bootstrapBrokers=my-cluster-kafka-bootstrap:9092
 ```
 
+Install with statically defined cluster at the CLI, but with a non-default service account assigned to the deployment.
+
+```
+helm install https://github.com/lightbend/kafka-lag-exporter/releases/download/v0.5.1/kafka-lag-exporter-0.5.1.tgz \
+  --name kafka-lag-exporter \
+  --namespace myproject \
+  --set clusters\[0\].name=my-cluster \
+  --set clusters\[0\].bootstrapBrokers=my-cluster-kafka-bootstrap:9092
+  --set serviceAccount.create=true
+```
+
 Run a debug install (`DEBUG` logging, debug helm chart install, force docker pull policy to `Always`).
 
 ```

charts/kafka-lag-exporter/templates/000-ServiceAccount.yaml

@@ -1,3 +1,4 @@
+{{- if or .Values.watchers.strimzi .Values.serviceAccount.create -}}
 apiVersion: v1
 kind: ServiceAccount
 metadata:
@@ -6,4 +7,5 @@ metadata:
     app.kubernetes.io/name: {{ include "kafka-lag-exporter.name" . }}
     helm.sh/chart: {{ include "kafka-lag-exporter.chart" . }}
     app.kubernetes.io/instance: {{ .Release.Name }}
-    app.kubernetes.io/managed-by: {{ .Release.Service }}
+    app.kubernetes.io/managed-by: {{ .Release.Service }}
+{{- end }}

charts/kafka-lag-exporter/templates/040-Deployment.yaml

@@ -23,7 +23,9 @@ spec:
         app.kubernetes.io/name: {{ include "kafka-lag-exporter.name" . }}
         app.kubernetes.io/instance: {{ .Release.Name }}
     spec:
+      {{- if or .Values.watchers.strimzi .Values.serviceAccount.create -}}
       serviceAccountName: {{ include "kafka-lag-exporter.fullname" . }}-serviceaccount
+      {{- end }}
       containers:
         - name: {{ .Chart.Name }}
           image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"

charts/kafka-lag-exporter/values.yaml

@@ -33,6 +33,11 @@ watchers:
   ## The Strimzi Cluster Watcher automatically watches for `kafka.strimzi.io` group, `Kafka` kind resources and will
   ## configure the Kafka Lag Exporter appropriately.
   strimzi: false
+## Applicable only in non-Strimzi installation. If true, a service account will be created and bind to the deployment.
+## Otherwise, the default service account for the namespace will be used.
+serviceAccount:
+  create: false
+
 ## You can use regex to control the metrics exposed by Prometheus endpoint.
 ## Any metric that matches one of the regex in the whitelist will be exposed.
 ## For example, if you only wish to expose the max lag metrics, use either: