feat: Allow adding extra service selector labels in ServiceMonitor (#673)

Signed-off-by: Erhhung Yuan <[email protected]>

Author: erhhung

charts/opensearch/CHANGELOG.md

@@ -22,6 +22,16 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Removed
 ### Fixed
 ### Security
+---
+## [3.0.1]
+### Added
+- Allow adding extra selector labels in ServiceMonitor
+### Changed
+### Deprecated
+### Removed
+### Fixed
+### Security
 
 [Unreleased]: https://github.com/opensearch-project/helm-charts/compare/opensearch-3.0.0...HEAD
 [3.0.0]: https://github.com/opensearch-project/helm-charts/compare/opensearch-2.33.0...opensearch-3.0.0
+[3.0.1]: https://github.com/opensearch-project/helm-charts/compare/opensearch-3.0.0...opensearch-3.0.1

charts/opensearch/Chart.yaml

@@ -15,7 +15,7 @@ type: application
 # This is the chart version. This version number should be incremented each time you make changes
 # to the chart and its templates, including the app version.
 # Versions are expected to follow Semantic Versioning (https://semver.org/)
-version: 3.0.0
+version: 3.0.1
 
 # This is the version number of the application being deployed. This version number should be
 # incremented each time you make changes to the application. Versions are not expected to

charts/opensearch/templates/serviceMonitor.yaml

@@ -13,6 +13,9 @@ spec:
   selector:
     matchLabels:
       {{- include "opensearch.selectorLabels" . | nindent 6 }}
+      {{- with .Values.serviceMonitor.selectorLabels }}
+        {{- toYaml . | nindent 6 }}
+      {{- end }}
   endpoints:
   - port: {{ .Values.service.httpPortName | default "http" }}
     interval: {{ .Values.serviceMonitor.interval }}

charts/opensearch/values.yaml

@@ -562,6 +562,13 @@ serviceMonitor:
   #  k8s.example.com/prometheus: kube-prometheus
   labels: {}
 
+  # additional service selector labels to be added to the ServiceMonitor
+  # (these could match extra .service.labels or .service.labelsHeadless
+  # to prevent Prometheus from unnecessarily scraping each target twice)
+  # selectorLabels:
+  #  prometheus.io/scrape: "true"
+  selectorLabels: {}
+
   # additional tlsConfig to be added to the ServiceMonitor
   tlsConfig: {}