[prometheus] Add "externalTrafficPolicy" to server's service (#5261)

* Add "externalTrafficPolicy" to Prometheus service.

Signed-off-by: Víctor Díaz Marco <[email protected]>

* Apply "externalTrafficPolicy" only if explicitly set.

Signed-off-by: Víctor Díaz Marco <[email protected]>

* Bump version.

Signed-off-by: Víctor Díaz Marco <[email protected]>

---------

Signed-off-by: Víctor Díaz Marco <[email protected]>
Co-authored-by: MH <[email protected]>
Co-authored-by: zeritti <[email protected]>

Author: 3 people

charts/prometheus/Chart.yaml

@@ -1,7 +1,7 @@
 apiVersion: v2
 name: prometheus
 appVersion: v3.1.0
-version: 27.2.0
+version: 27.3.0
 kubeVersion: ">=1.19.0-0"
 description: Prometheus is a monitoring system and time series database.
 home: https://prometheus.io/

charts/prometheus/templates/service.yaml

@@ -29,6 +29,9 @@ spec:
   {{- range $cidr := .Values.server.service.loadBalancerSourceRanges }}
     - {{ $cidr }}
   {{- end }}
+{{- end }}
+{{- if .Values.server.service.externalTrafficPolicy }}
+  externalTrafficPolicy: {{ .Values.server.service.externalTrafficPolicy }}
 {{- end }}
   ports:
     - name: http

charts/prometheus/values.yaml

@@ -724,6 +724,8 @@ server:
     servicePort: 80
     sessionAffinity: None
     type: ClusterIP
+    ## externalTrafficPolicy is applicable to service with externally-facing addresses (NodePorts, ExternalIPs, and LoadBalancer IPs)
+    externalTrafficPolicy: ""
 
     ## Enable gRPC port on service to allow auto discovery with thanos-querier
     gRPC: