Add Prometheus metrics support

bitnami/fluentd/templates/forwarder-configmap.yaml

@@ -69,3 +69,36 @@ data:
         flush_interval 10s
       </buffer>
     </match>
+  {{- if .Values.metrics.enabled }}
+  metrics.conf: |
+    # Prometheus Exporter Plugin
+    # input plugin that exports metrics
+    <source>
+      @type prometheus
+      port {{ .Values.metrics.service.port }}
+    </source>
+
+    # input plugin that collects metrics from MonitorAgent
+    <source>
+      @type prometheus_monitor
+      <labels>
+        host ${hostname}
+      </labels>
+    </source>
+
+    # input plugin that collects metrics for output plugin
+    <source>
+      @type prometheus_output_monitor
+      <labels>
+        host ${hostname}
+      </labels>
+    </source>
+
+    # input plugin that collects metrics for in_tail plugin
+    <source>
+      @type prometheus_tail_monitor
+      <labels>
+        host ${hostname}
+      </labels>
+    </source>
+  {{- end }}

bitnami/fluentd/templates/forwarder-daemonset.yaml

@@ -49,6 +49,11 @@ spec:
             - name: http
               containerPort: 9880
               protocol: TCP
+            {{- if .Values.metrics.enabled }}
+            - name: metrics
+              containerPort: {{ .Values.metrics.service.port }}
+              protocol: TCP
+            {{- end }}
           livenessProbe:
             httpGet:
               path: /fluentd.healthcheck?json=%7B%22ping%22%3A+%22pong%22%7D

bitnami/fluentd/templates/svc.yaml

@@ -5,11 +5,17 @@ metadata:
   labels:
     {{- include "fluentd.labels" . | nindent 4 }}
     app.kubernetes.io/component: forwarder
+{{- if or (and .Values.metrics.enabled .Values.metrics.service.annotations) .Values.service.annotations }}
+  annotations:
+  {{- if and .Values.metrics.enabled .Values.metrics.service.annotations }}
+    {{- tpl (toYaml .Values.metrics.service.annotations) $ | nindent 4 }}
+  {{- end }}
+  {{- if and .Values.service.annotations }}
+    {{- tpl (toYaml .Values.service.annotations) $ | nindent 4 }}
+  {{- end }}
+{{- end }}
 spec:
   type: {{ .Values.service.type }}
-  {{- if .Values.service.nodePort }}
-  nodePort: {{ .Values.service.nodePort }}
-  {{- end }}
   {{- if eq .Values.service.type "LoadBalancer" }} {{- if .Values.service.loadBalancerIP }}
   loadBalancerIP: {{ .Values.service.loadBalancerIP }}
   {{- end }} {{- end }}
@@ -17,8 +23,15 @@ spec:
   ports:
     - name: http
       targetPort: http
-      protocol: TCP
       port: {{ .Values.service.port }}
+      {{- if .Values.service.nodePort }}
+      nodePort: {{ .Values.service.nodePort }}
+      {{- end }}
+    {{- if .Values.metrics.enabled }}
+    - name: metrics
+      port: {{ .Values.metrics.service.port }}
+      targetPort: metrics
+    {{- end }}
   selector:
     app.kubernetes.io/name: {{ include "fluentd.name" . }}
     app.kubernetes.io/instance: {{ .Release.Name }}

bitnami/fluentd/values.yaml

@@ -211,11 +211,22 @@ serviceAccount:
   # name:
 
 ## Role Based Access
-## Ref: https://kubernetes.io/docs/admin/authorization/rbac/
+## ref: https://kubernetes.io/docs/admin/authorization/rbac/
 ##
 rbac:
   create: true
 
+## Prometheus metrics 
+## ref: https://github.com/fluent/fluent-plugin-prometheus/blob/master/README.md
+##
+metrics:
+  enabled: false
+  service:
+    port: 24231
+    annotations:
+      prometheus.io/scrape: "true"
+      prometheus.io/port: "24231"
+      prometheus.io/path: "/metrics"
 
 service:
   type: ClusterIP