feat(helm): add prometheus resources to monitor (#2958)

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---

I do not know, how you run helm-docs ....


otherwise i would like to add somewhere:
````markdown
* Works well with [Prometheus Operator](https://prometheus-operator.dev/) ([Helmchart](https://artifacthub.io/packages/helm/prometheus-community/kube-prometheus-stack)) and there setup of [Grafana](https://grafana.com/grafana/), by enabling following values:
```yaml
prometheus:
  servicemonitor:
    enabled: true
    labels:
      release: "kube-prometheus-stack"
  rules:
    enabled: true # will deploy alert rules
    additionalLabels:
      release: "kube-prometheus-stack"
grafana:
  dashboards:
    enabled: true # will deploy default dashboards 
```
PS: The labels `release=kube-prometheus-stack` is setup with the helmchart of the Prometheus Operator. For Grafana Dashboards it maybe need scan enable to scan in correct namespaces (or ALL), enabled by `sidecar.dashboards.searchNamespace` in [Helmchart of grafana](https://artifacthub.io/packages/helm/grafana/grafana) (which is part of PrometheusOperator, so `grafana.sidecar.dashboards.searchNamespace`) 
````

Maybe also put somewhere the Screenshot of that Grafana Dashboard:
https://grafana.com/grafana/dashboards/13916-dendrite/

---


@S7evinK do you take a look?

Signed-off-by: genofire <geno+dev@fireorbit.de>

helm/dendrite/.helm-docs/monitoring.gotmpl

@@ -0,0 +1,22 @@
+{{ define "chart.monitoringSection" }}
+## Monitoring
+
+[![Grafana Dashboard](https://grafana.com/api/dashboards/13916/images/9894/image)](https://grafana.com/grafana/dashboards/13916-dendrite/)
+
+* Works well with [Prometheus Operator](https://prometheus-operator.dev/) ([Helmchart](https://artifacthub.io/packages/helm/prometheus-community/kube-prometheus-stack)) and their setup of [Grafana](https://grafana.com/grafana/), by enabling the following values:
+```yaml
+prometheus:
+  servicemonitor:
+    enabled: true
+    labels:
+      release: "kube-prometheus-stack"
+  rules:
+    enabled: true # will deploy alert rules
+    labels:
+      release: "kube-prometheus-stack"
+grafana:
+  dashboards:
+    enabled: true # will deploy default dashboards 
+```
+PS: The label `release=kube-prometheus-stack` is setup with the helmchart of the Prometheus Operator. For Grafana Dashboards it may be necessary to enable scanning in the correct namespaces (or ALL), enabled by `sidecar.dashboards.searchNamespace` in [Helmchart of grafana](https://artifacthub.io/packages/helm/grafana/grafana) (which is part of PrometheusOperator, so `grafana.sidecar.dashboards.searchNamespace`) 
+{{ end }}

helm/dendrite/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v2
 name: dendrite
-version: "0.11.1"
+version: "0.11.2"
 appVersion: "0.11.1"
 description: Dendrite Matrix Homeserver
 type: application

helm/dendrite/README.md

@@ -1,6 +1,6 @@
 # dendrite
 
-![Version: 0.11.1](https://img.shields.io/badge/Version-0.11.1-informational?style=flat-square) ![Type: application](https://img.shields.io/badge/Type-application-informational?style=flat-square) ![AppVersion: 0.11.1](https://img.shields.io/badge/AppVersion-0.11.1-informational?style=flat-square)
+![Version: 0.11.2](https://img.shields.io/badge/Version-0.11.2-informational?style=flat-square) ![Type: application](https://img.shields.io/badge/Type-application-informational?style=flat-square) ![AppVersion: 0.11.1](https://img.shields.io/badge/AppVersion-0.11.1-informational?style=flat-square)
 Dendrite Matrix Homeserver
 
 Status: **NOT PRODUCTION READY**
@@ -146,3 +146,35 @@ Create a folder `appservices` and place your configurations in there.  The confi
 | ingress.tls | list | `[]` |  |
 | service.type | string | `"ClusterIP"` |  |
 | service.port | int | `8008` |  |
+| prometheus.servicemonitor.enabled | bool | `false` | Enable ServiceMonitor for Prometheus-Operator for scrape metric-endpoint |
+| prometheus.servicemonitor.labels | object | `{}` | Extra Labels on ServiceMonitor for selector of Prometheus Instance |
+| prometheus.rules.enabled | bool | `false` | Enable PrometheusRules for Prometheus-Operator for setup alerting |
+| prometheus.rules.labels | object | `{}` | Extra Labels on PrometheusRules for selector of Prometheus Instance |
+| prometheus.rules.additionalRules | list | `[]` | additional alertrules (no default alertrules are provided) |
+| grafana.dashboards.enabled | bool | `false` |  |
+| grafana.dashboards.labels | object | `{"grafana_dashboard":"1"}` | Extra Labels on ConfigMap for selector of grafana sidecar |
+| grafana.dashboards.annotations | object | `{}` | Extra Annotations on ConfigMap additional config in grafana sidecar |
+
+## Monitoring
+
+[![Grafana Dashboard](https://grafana.com/api/dashboards/13916/images/9894/image)](https://grafana.com/grafana/dashboards/13916-dendrite/)
+
+* Works well with [Prometheus Operator](https://prometheus-operator.dev/) ([Helmchart](https://artifacthub.io/packages/helm/prometheus-community/kube-prometheus-stack)) and their setup of [Grafana](https://grafana.com/grafana/), by enabling the following values:
+```yaml
+prometheus:
+  servicemonitor:
+    enabled: true
+    labels:
+      release: "kube-prometheus-stack"
+  rules:
+    enabled: true # will deploy alert rules
+    labels:
+      release: "kube-prometheus-stack"
+grafana:
+  dashboards:
+    enabled: true # will deploy default dashboards
+```
+PS: The label `release=kube-prometheus-stack` is setup with the helmchart of the Prometheus Operator. For Grafana Dashboards it may be necessary to enable scanning in the correct namespaces (or ALL), enabled by `sidecar.dashboards.searchNamespace` in [Helmchart of grafana](https://artifacthub.io/packages/helm/grafana/grafana) (which is part of PrometheusOperator, so `grafana.sidecar.dashboards.searchNamespace`)
+
+----------------------------------------------
+Autogenerated from chart metadata using [helm-docs vv1.11.0](https://github.com/norwoodj/helm-docs/releases/vv1.11.0)

helm/dendrite/README.md.gotmpl

@@ -10,4 +10,5 @@
 {{ template "chart.sourcesSection" . }}
 {{ template "chart.requirementsSection" . }}
 {{ template "chart.valuesSection" . }}
+{{ template "chart.monitoringSection" . }}
 {{ template "helm-docs.versionFooter" . }}

helm/dendrite/ci/ct-ingress-values.yaml

@@ -11,3 +11,8 @@ dendrite_config:
 
 ingress:
   enabled: true
+
+# dashboard is an ConfigMap with labels - it does not harm on testing
+grafana:
+  dashboards:
+    enabled: true

helm/dendrite/templates/configmap_grafana_dashboards.yaml

@@ -0,0 +1,16 @@
+{{- if .Values.grafana.dashboards.enabled }}
+{{- range $path, $bytes := .Files.Glob "grafana_dashboards/*" }}
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: {{ include "dendrite.fullname" $ }}-grafana-dashboards-{{ base $path }}
+  labels:
+    {{- include "dendrite.labels" $ | nindent 4 }}
+    {{- toYaml $.Values.grafana.dashboards.labels | nindent 4 }}
+  annotations:
+    {{- toYaml $.Values.grafana.dashboards.annotations | nindent 4 }}
+data:
+  {{- ($.Files.Glob $path ).AsConfig | nindent 2 }}
+{{- end }}
+{{- end }}

helm/dendrite/templates/prometheus-rules.yaml

@@ -0,0 +1,16 @@
+{{- if and ( .Values.prometheus.rules.enabled ) ( .Capabilities.APIVersions.Has "monitoring.coreos.com/v1" ) }}
+---
+apiVersion: monitoring.coreos.com/v1
+kind: PrometheusRule
+metadata:
+  name: {{ include "dendrite.fullname" . }}
+  labels:
+    {{- include "dendrite.labels" . | nindent 4 }}
+    {{- toYaml .Values.prometheus.rules.labels | nindent 4 }}
+spec:
+  groups:
+  {{- if .Values.prometheus.rules.additionalRules }}
+  - name: {{ template "dendrite.name" . }}-Additional
+    rules: {{- toYaml .Values.prometheus.rules.additionalRules | nindent 4 }}
+  {{- end }}
+{{- end }}

helm/dendrite/templates/secrets.yaml

@@ -1,15 +1,15 @@
-{{ if (gt (len (.Files.Glob "appservices/*")) 0) }}
+{{- if (gt (len (.Files.Glob "appservices/*")) 0) }}
 ---
 apiVersion: v1
 kind: Secret
 metadata:
   name: {{ include "dendrite.fullname" . }}-appservices-conf
-  namespace: {{ .Release.Namespace }}
 type: Opaque
 data:
 {{ (.Files.Glob "appservices/*").AsSecrets | indent 2 }}
-{{ end }}
+{{- end }}
-{{ if and .Values.signing_key.create (not .Values.signing_key.existingSecret) }}
+
+{{- if and .Values.signing_key.create (not .Values.signing_key.existingSecret) }}
 ---
 apiVersion: v1
 kind: Secret
@@ -17,17 +17,29 @@ metadata:
   annotations:
     helm.sh/resource-policy: keep
   name: {{ include "dendrite.fullname" . }}-signing-key
-  namespace: {{ .Release.Namespace }}
 type: Opaque
-{{ end }}
+{{- end }}
+
+{{- with .Values.dendrite_config.global.metrics }}
+{{- if .enabled }}
+---
+apiVersion: v1
+kind: Secret
+metadata:
+  name: {{ include "dendrite.fullname" $ }}-metrics-basic-auth
+type: Opaque
+stringData:
+  user: {{ .basic_auth.user | quote }}
+  password: {{ .basic_auth.password | quote }}
+{{- end }}
+{{- end }}
 
 ---
 apiVersion: v1
 kind: Secret
-type: Opaque
 metadata:
   name: {{ include "dendrite.fullname" . }}-conf
-  namespace: {{ .Release.Namespace }}
+type: Opaque
 stringData:
   dendrite.yaml: |
     {{ toYaml ( mustMergeOverwrite .Values.dendrite_config  ( fromYaml (include "override.config" .) ) .Values.dendrite_config ) | nindent 4 }}

helm/dendrite/templates/servicemonitor.yaml

@@ -0,0 +1,26 @@
+{{- if and 
+  (and .Values.prometheus.servicemonitor.enabled .Values.dendrite_config.global.metrics.enabled )
+  ( .Capabilities.APIVersions.Has "monitoring.coreos.com/v1" )
+}}
+---
+apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: {{ include "dendrite.fullname" . }}
+  labels:
+    {{- include "dendrite.labels" . | nindent 4 }}
+    {{- toYaml .Values.prometheus.servicemonitor.labels | nindent 4 }}
+spec:
+  endpoints:
+    - port: http
+      basicAuth:
+        username:
+          name: {{ include "dendrite.fullname" . }}-metrics-basic-auth
+          key: "user"
+        password:
+          name: {{ include "dendrite.fullname" . }}-metrics-basic-auth
+          key: "password"
+  selector:
+    matchLabels:
+      {{- include "dendrite.selectorLabels" . | nindent 6 }}
+{{- end }}

helm/dendrite/values.yaml

@@ -348,3 +348,26 @@ ingress:
 service:
   type: ClusterIP
   port: 8008
+
+prometheus:
+  servicemonitor:
+    # -- Enable ServiceMonitor for Prometheus-Operator for scrape metric-endpoint
+    enabled: false
+    # -- Extra Labels on ServiceMonitor for selector of Prometheus Instance
+    labels: {}
+  rules:
+    # -- Enable PrometheusRules for Prometheus-Operator for setup alerting
+    enabled: false
+    # -- Extra Labels on PrometheusRules for selector of Prometheus Instance
+    labels: {}
+    # -- additional alertrules (no default alertrules are provided)
+    additionalRules: []
+
+grafana:
+  dashboards:
+    enabled: false
+    # -- Extra Labels on ConfigMap for selector of grafana sidecar
+    labels:
+      grafana_dashboard: "1"
+    # -- Extra Annotations on ConfigMap additional config in grafana sidecar
+    annotations: {}