feat: add PrometheusTopologySharding feature gate (#7233)

Signed-off-by: dongjiang <dongjiang1989@126.com>

Documentation/operator.md

@@ -57,6 +57,7 @@ Usage of ./operator:
     	Feature gates are a set of key=value pairs that describe Prometheus-Operator features.
     	Available feature gates:
     	  PrometheusAgentDaemonSet: Enables the DaemonSet mode for PrometheusAgent (enabled: false)
+    	  PrometheusTopologySharding: Enables the zone aware sharding for Prometheus (enabled: false)
   -key-file string
     	- NOT RECOMMENDED FOR PRODUCTION - Path to private TLS certificate file.
   -kubelet-endpoints

pkg/operator/config.go

@@ -95,6 +95,10 @@ func DefaultConfig(cpu, memory string) Config {
 				description: "Enables the DaemonSet mode for PrometheusAgent",
 				enabled:     false,
 			},
+			PrometheusTopologyShardingFeature: FeatureGate{
+				description: "Enables the zone aware sharding for Prometheus",
+				enabled:     false,
+			},
 		},
 	}
 }

pkg/operator/feature_gates.go

@@ -25,6 +25,9 @@ import (
 const (
 	// PrometheusAgentDaemonSetFeature enables the DaemonSet mode for PrometheusAgent.
 	PrometheusAgentDaemonSetFeature FeatureGateName = "PrometheusAgentDaemonSet"
+
+	// PrometheusTopologySharding enables the zone aware sharding for Prometheus.
+	PrometheusTopologyShardingFeature FeatureGateName = "PrometheusTopologySharding"
 )
 
 type FeatureGateName string

pkg/prometheus/promcfg.go

@@ -65,14 +65,15 @@ func sanitizeLabelName(name string) string {
 // ConfigGenerator knows how to generate a Prometheus configuration which is
 // compatible with a given Prometheus version.
 type ConfigGenerator struct {
-	logger                 *slog.Logger
-	version                semver.Version
-	notCompatible          bool
-	prom                   monitoringv1.PrometheusInterface
-	useEndpointSlice       bool // Whether to use EndpointSlice for service discovery from `ServiceMonitor` objects.
-	scrapeClasses          map[string]monitoringv1.ScrapeClass
-	defaultScrapeClassName string
-	daemonSet              bool
+	logger                     *slog.Logger
+	version                    semver.Version
+	notCompatible              bool
+	prom                       monitoringv1.PrometheusInterface
+	useEndpointSlice           bool // Whether to use EndpointSlice for service discovery from `ServiceMonitor` objects.
+	scrapeClasses              map[string]monitoringv1.ScrapeClass
+	defaultScrapeClassName     string
+	daemonSet                  bool
+	prometheusTopologySharding bool
 }
 
 type ConfigGeneratorOption func(*ConfigGenerator)
@@ -90,6 +91,12 @@ func WithDaemonSet() ConfigGeneratorOption {
 	}
 }
 
+func WithPrometheusTopologySharding() ConfigGeneratorOption {
+	return func(cg *ConfigGenerator) {
+		cg.prometheusTopologySharding = true
+	}
+}
+
 // NewConfigGenerator creates a ConfigGenerator for the provided Prometheus resource.
 func NewConfigGenerator(
 	logger *slog.Logger,