Add relabel config support to ServiceMonitor

agents/prometheusoperator/lib.go

@@ -76,25 +76,33 @@ func (agent *PrometheusOperator) CreateOrUpdate(sp api.StatsAccessor, new *api.A
 		in.Labels = meta_util.OverwriteKeys(sp.ServiceMonitorAdditionalLabels(), new.Prometheus.ServiceMonitor.Labels)
 		core_util.EnsureOwnerReference(&in.ObjectMeta, owner)
 
+		in.Spec.TargetLabels = new.Prometheus.ServiceMonitor.TargetLabels
+		in.Spec.PodTargetLabels = new.Prometheus.ServiceMonitor.PodTargetLabels
+
 		in.Spec.NamespaceSelector = promapi.NamespaceSelector{
 			MatchNames: []string{sp.GetNamespace()},
 		}
+		podLabel := promapi.RelabelConfig{
+			SourceLabels: []promapi.LabelName{"__meta_kubernetes_endpoint_address_target_name"},
+			TargetLabel:  "pod",
+			Action:       "replace",
+		}
 		for _, p := range svc.Spec.Ports {
-			in.Spec.Endpoints = upsertMonitoringEndpoint(in.Spec.Endpoints, promapi.Endpoint{
-				Port:        p.Name,
-				Interval:    promapi.Duration(new.Prometheus.ServiceMonitor.Interval),
-				Path:        sp.Path(),
-				HonorLabels: true,
-				Scheme:      func() *promapi.Scheme { s := promapi.Scheme(sp.Scheme()); return &s }(),
-				TLSConfig:   sp.TLSConfig(),
-				RelabelConfigs: []promapi.RelabelConfig{
-					{
-						SourceLabels: []promapi.LabelName{"__meta_kubernetes_endpoint_address_target_name"},
-						TargetLabel:  "pod",
-						Action:       "replace",
-					},
-				},
-			})
+			ep := promapi.Endpoint{
+				Port:           p.Name,
+				Interval:       promapi.Duration(new.Prometheus.ServiceMonitor.Interval),
+				Path:           sp.Path(),
+				HonorLabels:    true,
+				Scheme:         func() *promapi.Scheme { s := promapi.Scheme(sp.Scheme()); return &s }(),
+				TLSConfig:      sp.TLSConfig(),
+				RelabelConfigs: []promapi.RelabelConfig{podLabel},
+			}
+			mep := findEndpoint(new.Prometheus.ServiceMonitor.Endpoints, ep.Port)
+			if mep != nil {
+				ep.RelabelConfigs = append([]promapi.RelabelConfig{podLabel}, mep.RelabelConfigs...)
+				ep.MetricRelabelConfigs = mep.MetricRelabelConfigs
+			}
+			in.Spec.Endpoints = upsertMonitoringEndpoint(in.Spec.Endpoints, ep)
 		}
 		in.Spec.Selector = metav1.LabelSelector{
 			MatchLabels: svc.Labels,
@@ -105,6 +113,15 @@ func (agent *PrometheusOperator) CreateOrUpdate(sp api.StatsAccessor, new *api.A
 	return vt, err
 }
 
+func findEndpoint(endpoints []api.Endpoint, port string) *api.Endpoint {
+	for _, ep := range endpoints {
+		if ep.Port == port {
+			return &ep
+		}
+	}
+	return nil
+}
+
 func (agent *PrometheusOperator) Delete(sp api.StatsAccessor) (kutil.VerbType, error) {
 	if !discovery.ExistsGroupKind(agent.k8sClient.Discovery(), promapi.SchemeGroupVersion.Group, promapi.ServiceMonitorsKind) {
 		return kutil.VerbUnchanged, errors.New("cluster does not support Prometheus operator")

api/v1/types.go

@@ -74,6 +74,53 @@ type ServiceMonitorSpec struct {
 	// Interval at which metrics should be scraped
 	// +optional
 	Interval string `json:"interval,omitempty"`
+
+	// targetLabels defines the labels which are transferred from the
+	// associated Kubernetes `Service` object onto the ingested metrics.
+	//
+	// +optional
+	TargetLabels []string `json:"targetLabels,omitempty"`
+	// podTargetLabels defines the labels which are transferred from the
+	// associated Kubernetes `Pod` object onto the ingested metrics.
+	//
+	// +optional
+	PodTargetLabels []string `json:"podTargetLabels,omitempty"`
+
+	// endpoints defines the list of endpoints part of this ServiceMonitor.
+	// Defines how to scrape metrics from Kubernetes [Endpoints](https://kubernetes.io/docs/concepts/services-networking/service/#endpoints) objects.
+	// In most cases, an Endpoints object is backed by a Kubernetes [Service](https://kubernetes.io/docs/concepts/services-networking/service/) object with the same name and labels.
+	// +required
+	Endpoints []Endpoint `json:"endpoints"`
+}
+
+// Endpoint defines an endpoint serving Prometheus metrics to be scraped by
+// Prometheus.
+//
+// +k8s:openapi-gen=true
+type Endpoint struct {
+	// port defines the name of the Service port which this endpoint refers to.
+	//
+	// It takes precedence over `targetPort`.
+	// +optional
+	Port string `json:"port,omitempty"`
+
+	// metricRelabelings defines the relabeling rules to apply to the
+	// samples before ingestion.
+	//
+	// +optional
+	MetricRelabelConfigs []promapi.RelabelConfig `json:"metricRelabelings,omitempty"`
+
+	// relabelings defines the relabeling rules to apply the target's
+	// metadata labels.
+	//
+	// The Operator automatically adds relabelings for a few standard Kubernetes fields.
+	//
+	// The original scrape job's name is available via the `__tmp_prometheus_job_name` label.
+	//
+	// More info: https://prometheus.io/docs/prometheus/latest/configuration/configuration/#relabel_config
+	//
+	// +optional
+	RelabelConfigs []promapi.RelabelConfig `json:"relabelings,omitempty"`
 }
 
 type PrometheusExporterSpec struct {