feat(argocd-image-updater): Optionally expose metrics (#1005)

* feat(argocd-image-updater): Optionally expose metrics

Signed-off-by: Jan Pieper <kontakt@jan-pieper.info>

* Apply suggestions from code review

Signed-off-by: Marco Kilchhofer <mkilchhofer@users.noreply.github.com>

* Add missing link references to README

Signed-off-by: Marco Kilchhofer <mkilchhofer@users.noreply.github.com>

Co-authored-by: Marco Kilchhofer <mkilchhofer@users.noreply.github.com>

charts/argocd-image-updater/Chart.yaml

@@ -2,7 +2,7 @@ apiVersion: v2
 name: argocd-image-updater
 description: A Helm chart for Argo CD Image Updater, a tool to automatically update the container images of Kubernetes workloads which are managed by Argo CD
 type: application
-version: 0.2.1
+version: 0.3.0
 appVersion: v0.10.1
 home: https://github.com/argoproj-labs/argocd-image-updater
 icon: https://argocd-image-updater.readthedocs.io/en/stable/assets/logo.png
@@ -15,4 +15,4 @@ maintainers:
     url: https://argoproj.github.io/
 annotations:
   artifacthub.io/changes: |
-    - "[Fixed]: Update default values example for extraArgs
+    - "[Added]: Ability to expose metrics and deploy a Prometheus ServiceMonitor"

charts/argocd-image-updater/README.md

@@ -66,13 +66,24 @@ The `config.registries` value can be used exactly as it looks in the documentati
 | config.argocd.serverAddress | string | `""` | Connect to the Argo CD API server at server address |
 | config.logLevel | string | `"info"` | ArgoCD Image Update log level |
 | config.registries | list | `[]` | ArgoCD Image Updater registries list configuration. More information [here](https://argocd-image-updater.readthedocs.io/en/stable/configuration/registries/) |
-| extraArgs | list | `[]` | Extra arguments for argocd-image-updater not defined in config.argocd |
+| extraArgs | list | `[]` | Extra arguments for argocd-image-updater not defined in `config.argocd`. If a flag contains both key and value, they need to be split to a new entry |
 | extraEnv | list | `[]` | Extra environment variables for argocd-image-updater |
 | fullnameOverride | string | `""` | Global fullname (argocd-image-updater.fullname in _helpers.tpl) override |
 | image.pullPolicy | string | `"Always"` | Default image pull policy |
 | image.repository | string | `"argoprojlabs/argocd-image-updater"` | Default image repository |
 | image.tag | string | `"v0.10.1"` | Default image tag |
 | imagePullSecrets | list | `[]` | ImagePullSecrets for the image updater deployment |
+| metrics.enabled | bool | `false` | Deploy metrics service |
+| metrics.service.annotations | object | `{}` | Metrics service annotations |
+| metrics.service.labels | object | `{}` | Metrics service labels |
+| metrics.service.servicePort | int | `8081` | Metrics service port |
+| metrics.serviceMonitor.additionalLabels | object | `{}` | Prometheus ServiceMonitor labels |
+| metrics.serviceMonitor.enabled | bool | `false` | Enable a prometheus ServiceMonitor |
+| metrics.serviceMonitor.interval | string | `"30s"` | Prometheus ServiceMonitor interval |
+| metrics.serviceMonitor.metricRelabelings | list | `[]` | Prometheus [MetricRelabelConfigs] to apply to samples before ingestion |
+| metrics.serviceMonitor.namespace | string | `""` | Prometheus ServiceMonitor namespace |
+| metrics.serviceMonitor.relabelings | list | `[]` | Prometheus [RelabelConfigs] to apply to samples before scraping |
+| metrics.serviceMonitor.selector | object | `{}` | Prometheus ServiceMonitor selector |
 | nameOverride | string | `""` | Global name (argocd-image-updater.name in _helpers.tpl) override |
 | nodeSelector | object | `{}` | Kubernetes nodeSelector settings for the deployment |
 | podAnnotations | object | `{}` | Pod Annotations for the deployment |
@@ -85,3 +96,9 @@ The `config.registries` value can be used exactly as it looks in the documentati
 | serviceAccount.create | bool | `true` | Specifies whether a service account should be created |
 | serviceAccount.name | string | `""` | The name of the service account to use. If not set and create is true, a name is generated using the fullname template |
 | tolerations | list | `[]` | Kubernetes toleration settings for the deployment |
+
+----------------------------------------------
+Autogenerated from chart metadata using [helm-docs v1.5.0](https://github.com/norwoodj/helm-docs/releases/v1.5.0)
+
+[MetricRelabelConfigs]: https://prometheus.io/docs/prometheus/latest/configuration/configuration/#metric_relabel_configs
+[RelabelConfigs]: https://prometheus.io/docs/prometheus/latest/configuration/configuration/#relabel_config

charts/argocd-image-updater/README.md.gotmpl

@@ -56,3 +56,8 @@ If you need support for ECR, you can reference [this issue](https://github.com/a
 The `config.registries` value can be used exactly as it looks in the documentation as it gets dumped directly into a configmap in this chart.
 
 {{ template "chart.valuesSection" . }}
+
+{{ template "helm-docs.versionFooter" . }}
+
+[MetricRelabelConfigs]: https://prometheus.io/docs/prometheus/latest/configuration/configuration/#metric_relabel_configs
+[RelabelConfigs]: https://prometheus.io/docs/prometheus/latest/configuration/configuration/#relabel_config

charts/argocd-image-updater/templates/deployment.yaml

@@ -60,6 +60,11 @@ spec:
           imagePullPolicy: {{ .Values.image.pullPolicy }}
           ports:
             - containerPort: 8080
+            {{ if .Values.metrics.enabled }}
+            - name: metrics
+              containerPort: 8081
+              protocol: TCP
+            {{- end }}
           readinessProbe:
             httpGet:
               path: /healthz

charts/argocd-image-updater/templates/metrics-service.yaml

@@ -0,0 +1,25 @@
+{{- if .Values.metrics.enabled }}
+apiVersion: v1
+kind: Service
+metadata:
+  {{- if .Values.metrics.service.annotations }}
+  annotations:
+    {{- range $key, $value := .Values.metrics.service.annotations }}
+    {{ $key }}: {{ $value | quote }}
+    {{- end }}
+  {{- end }}
+  labels:
+    {{- include "argocd-image-updater.labels" . | nindent 4 }}
+    {{- with .Values.metrics.service.labels }}
+      {{- toYaml . | nindent 4 }}
+    {{- end }}
+  name: {{ include "argocd-image-updater.fullname" . }}-metrics
+spec:
+  ports:
+    - name: metrics
+      protocol: TCP
+      port: {{ .Values.metrics.service.servicePort }}
+      targetPort: metrics
+  selector:
+    {{- include "argocd-image-updater.selectorLabels" . | nindent 4 }}
+{{- end }}

charts/argocd-image-updater/templates/servicemonitor.yaml

@@ -0,0 +1,38 @@
+{{- if and .Values.metrics.enabled .Values.metrics.serviceMonitor.enabled }}
+apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: {{ include "argocd-image-updater.fullname" . }}-metrics
+  {{- with .Values.metrics.serviceMonitor.namespace }}
+  namespace: {{ . }}
+  {{- end }}
+  labels:
+    {{- include "argocd-image-updater.labels" . | nindent 4 }}
+    {{- with .Values.metrics.serviceMonitor.selector }}
+      {{- toYaml . | nindent 4 }}
+    {{- end }}
+    {{- with .Values.metrics.serviceMonitor.additionalLabels }}
+      {{- toYaml . | nindent 4 }}
+    {{- end }}
+spec:
+  endpoints:
+    - port: metrics
+      {{- with .Values.metrics.serviceMonitor.interval }}
+      interval: {{ . }}
+      {{- end }}
+      path: /metrics
+      {{- with .Values.metrics.serviceMonitor.relabelings }}
+      relabelings:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.metrics.serviceMonitor.metricRelabelings }}
+      metricRelabelings:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+  namespaceSelector:
+    matchNames:
+      - {{ .Release.Namespace }}
+  selector:
+    matchLabels:
+      {{- include "argocd-image-updater.selectorLabels" . | nindent 6 }}
+{{- end }}

charts/argocd-image-updater/values.yaml

@@ -15,7 +15,7 @@ nameOverride: ""
 # -- Global fullname (argocd-image-updater.fullname in _helpers.tpl) override
 fullnameOverride: ""
 
-# -- Extra arguments for argocd-image-updater not defined in config.argocd
+# -- Extra arguments for argocd-image-updater not defined in `config.argocd`.
 # If a flag contains both key and value, they need to be split to a new entry
 extraArgs: []
   # - --disable-kubernetes
@@ -112,3 +112,32 @@ tolerations: []
 
 # -- Kubernetes affinity settings for the deployment
 affinity: {}
+
+# Metrics configuration
+metrics:
+  # -- Deploy metrics service
+  enabled: false
+  service:
+    # -- Metrics service annotations
+    annotations: {}
+    # -- Metrics service labels
+    labels: {}
+    # -- Metrics service port
+    servicePort: 8081
+  serviceMonitor:
+    # -- Enable a prometheus ServiceMonitor
+    enabled: false
+    # -- Prometheus ServiceMonitor interval
+    interval: 30s
+    # -- Prometheus [RelabelConfigs] to apply to samples before scraping
+    relabelings: []
+    # -- Prometheus [MetricRelabelConfigs] to apply to samples before ingestion
+    metricRelabelings: []
+    # -- Prometheus ServiceMonitor selector
+    selector: {}
+      # promtheus: kube-prometheus
+
+    # -- Prometheus ServiceMonitor namespace
+    namespace: ""
+    # -- Prometheus ServiceMonitor labels
+    additionalLabels: {}