Annotate a service with the pool used to provide its IP

when we have multiple configurations tied to the ipaddresspool, it'd be useful to see which pool was used to assign the ip to a given service. You can see it by looking service's annotation "metallb.universe.tf/ip-allocated-from-pool".

Signed-off-by: cyclinder <qifeng.guo@daocloud.io>

controller/main.go

@@ -87,14 +87,18 @@ func (c *controller) SetBalancer(l log.Logger, name string, svcRo *v1.Service, _
 	}
 
 	if !reflect.DeepEqual(svcRo.Status, svc.Status) {
-		var st v1.ServiceStatus
-		st, svc = svc.Status, svcRo.DeepCopy()
-		svc.Status = st
-		if err := c.client.UpdateStatus(svc); err != nil {
-			level.Error(l).Log("op", "updateServiceStatus", "error", err, "msg", "failed to update service status")
-			return controllers.SyncStateError
-		}
+		updateSvcStatus(svc, svcRo)
+	}
+
+	if !reflect.DeepEqual(svcRo.Annotations, svc.Annotations) {
+		updateSvcAnnotations(svc, svcRo)
 	}
+
+	if err := c.client.UpdateStatus(svc); err != nil {
+		level.Error(l).Log("op", "updateServiceStatus", "error", err, "msg", "failed to update service")
+		return controllers.SyncStateError
+	}
+
 	level.Info(l).Log("event", "serviceUpdated", "msg", "updated service object")
 	return successRes
 }

controller/service.go

@@ -30,8 +30,9 @@ import (
 )
 
 const (
-	annotationAddressPool     = "metallb.universe.tf/address-pool"
-	annotationLoadBalancerIPs = "metallb.universe.tf/loadBalancerIPs"
+	annotationAddressPool        = "metallb.universe.tf/address-pool"
+	annotationLoadBalancerIPs    = "metallb.universe.tf/loadBalancerIPs"
+	annotationIPAllocateFromPool = "metallb.universe.tf/ip-allocated-from-pool"
 )
 
 func (c *controller) convergeBalancer(l log.Logger, key string, svc *v1.Service) bool {
@@ -161,13 +162,18 @@ func (c *controller) convergeBalancer(l log.Logger, key string, svc *v1.Service)
 		lbIngressIPs = append(lbIngressIPs, v1.LoadBalancerIngress{IP: lbIP.String()})
 	}
 	svc.Status.LoadBalancer.Ingress = lbIngressIPs
+	if svc.Annotations == nil {
+		svc.Annotations = make(map[string]string)
+	}
+	svc.Annotations[annotationIPAllocateFromPool] = pool
 	return true
 }
 
 // clearServiceState clears all fields that are actively managed by
 // this controller.
 func (c *controller) clearServiceState(key string, svc *v1.Service) {
 	c.ips.Unassign(key)
+	delete(svc.Annotations, annotationIPAllocateFromPool)
 	svc.Status.LoadBalancer = v1.LoadBalancerStatus{}
 }
 
@@ -260,3 +266,18 @@ func isEqualIPs(ipsA, ipsB []net.IP) bool {
 	})
 	return reflect.DeepEqual(ipsA, ipsB)
 }
+
+// updateSvcStatus updating svc's status and svcRo's status
+func updateSvcStatus(svc, svcRo *v1.Service) {
+	var st v1.ServiceStatus
+	st, svc = svc.Status, svcRo.DeepCopy()
+	// we need be update svcRo's status
+	svc.Status, svcRo.Status = st, st
+}
+
+// updateSvcAnnotations updating svc's annotations
+func updateSvcAnnotations(svc, svcRo *v1.Service) {
+	var annotations map[string]string
+	annotations, svc = svc.Annotations, svcRo.DeepCopy()
+	svc.Annotations = annotations
+}

e2etest/l2tests/l2.go

@@ -676,10 +676,14 @@ var _ = ginkgo.Describe("L2", func() {
 			err = config.ValidateIPInRange([]metallbv1beta1.IPAddressPool{pool}, ingressIP)
 			framework.ExpectNoError(err)
 
+			ginkgo.By("validate annotating a service with the pool used to provide its IP")
+			framework.ExpectEqual(svc.Annotations["metallb.universe.tf/ip-allocated-from-pool"], pool.Name)
+
 			services = append(services, svc)
 			servicesIngressIP = append(servicesIngressIP, ingressIP)
 
 			for j := 0; j <= i; j++ {
+
 				ginkgo.By(fmt.Sprintf("validate service %d IP didn't change", j+1))
 				ip := e2eservice.GetIngressPoint(&services[j].Status.LoadBalancer.Ingress[0])
 				framework.ExpectEqual(ip, servicesIngressIP[j])