feat: add configuration for logging-operator metrics ServiceMonitor

Enable the fluentbit ServiceMonitor by default.

charts/lagoon-logging/templates/logging.yaml

@@ -12,6 +12,10 @@ spec:
         fsGroup: 0
     scaling:
       replicas: {{ .Values.fluentdReplicaCount }}
+  {{- with .Values.fluentdMetrics }}
+    metrics:
+    {{- toYaml . | nindent 6 }}
+  {{- end }}
   fluentbit:
     # Enable a default liveness check to avoid stuck pods.
     # At the time of writing this just hits the metrics endpoint.
@@ -26,4 +30,8 @@ spec:
     tolerations:
     {{- toYaml . | nindent 4 }}
   {{- end }}
+  {{- with .Values.fluentbitMetrics }}
+    metrics:
+    {{- toYaml . | nindent 6 }}
+  {{- end }}
   controlNamespace: {{ .Release.Namespace | quote }}

charts/lagoon-logging/values.yaml

@@ -261,6 +261,18 @@ fluentbitTolerations:
   key: lagoon.sh/spot
   operator: Exists
 
+# Expose metrics of the Logging Operator's fluentbit daemonset and fluentd
+# statefulset via a Prometheus Operator compatible ServiceMonitor object.
+#
+# The fluentd serviceMonitor is disabled by default until a use-case is found.
+#
+# See here for full documentation of this field:
+# https://kube-logging.dev/docs/operation/logging-operator-monitoring/#metrics-variables
+fluentbitMetrics:
+  serviceMonitor: true
+# fluentdMetrics:
+#   serviceMonitor: true
+
 # This chart assumes the container runtime is containerd, which puts the log
 # message in the `message` field of the log record.
 #