pkg/metrics/cinder.go only publish new metrics on successful openstack calls

Author: chrischdi

pkg/metrics/cinder.go

@@ -6,7 +6,6 @@ import (
 	"github.com/gophercloud/gophercloud"
 	"github.com/gophercloud/gophercloud/openstack/blockstorage/extensions/quotasets"
 	"github.com/gophercloud/gophercloud/openstack/blockstorage/v2/volumes"
-	"github.com/gophercloud/gophercloud/pagination"
 	"github.com/prometheus/client_golang/prometheus"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/client-go/kubernetes"
@@ -93,39 +92,48 @@ func registerCinderMetrics() {
 // PublishCinderMetrics makes the list request to the blockstorage api and passes
 // the result to a publish function.
 func PublishCinderMetrics(client *gophercloud.ServiceClient, clientset *kubernetes.Clientset, tenantID string) error {
+	// first step: gather the data
+
 	// get the cinder pvs to add metadata
 	pvs, err := getPVsByCinderID(clientset)
 	if err != nil {
 		return err
 	}
 
-	// cinderQuotaVolumes and CinderQuotaVolumesGigabytes are not dynamic and do not need to be reset
-	cinderVolumeCreated.Reset()
-	cinderVolumeUpdatedAt.Reset()
-	cinderVolumeStatus.Reset()
-	cinderVolumeSize.Reset()
-	cinderVolumeAttachedAt.Reset()
-
-	// get all volumes and publish them
+	// get all volumes from openstack
 	mc := newOpenStackMetric("volume", "list")
-	pager := volumes.List(client, volumes.ListOpts{})
-	err = pager.EachPage(func(page pagination.Page) (bool, error) {
-		return publishVolumesPage(page, pvs)
-	})
+	pages, err := volumes.List(client, volumes.ListOpts{}).AllPages()
 	if mc.Observe(err) != nil {
 		// only warn, maybe the next list will work.
 		klog.Warningf("Unable to list volumes: %v", err)
 		return err
 	}
+	volumesList, err := volumes.ExtractVolumes(pages)
+	if err != nil {
+		return err
+	}
 
+	// get quotas form openstack
 	mc = newOpenStackMetric("volume_quotasets_usage", "get")
-	q, err := quotasets.GetUsage(client, tenantID).Extract()
+	quotas, err := quotasets.GetUsage(client, tenantID).Extract()
 	if mc.Observe(err) != nil {
 		// only warn, maybe the next get will work.
 		klog.Warningf("Unable to get quotas: %v", err)
 		return err
 	}
-	publishCinderQuotas(q)
+
+	// second step: reset the old metrics
+	// cinderQuotaVolumes and CinderQuotaVolumesGigabytes are not dynamic and do not need to be reset
+	cinderVolumeCreated.Reset()
+	cinderVolumeUpdatedAt.Reset()
+	cinderVolumeStatus.Reset()
+	cinderVolumeSize.Reset()
+	cinderVolumeAttachedAt.Reset()
+
+	// third step: publish the metrics
+	publishVolumes(volumesList, pvs)
+
+	publishCinderQuotas(quotas)
 	return nil
 }
 
@@ -142,21 +150,15 @@ func publishCinderQuotas(q quotasets.QuotaUsageSet) {
 	cinderQuotaVolumesGigabyte.WithLabelValues("allocated").Set(float64(q.Gigabytes.Allocated))
 }
 
-// publishVolumesPage iterates over a page, the result of a list request
-func publishVolumesPage(page pagination.Page, pvs map[string]corev1.PersistentVolume) (bool, error) {
-	vList, err := volumes.ExtractVolumes(page)
-	if err != nil {
-		return false, err
-	}
-
+// publishVolumes iterates over a page, the result of a list request
+func publishVolumes(vList []volumes.Volume, pvs map[string]corev1.PersistentVolume) {
 	for _, v := range vList {
 		if pv, ok := pvs[v.ID]; ok {
 			publishVolumeMetrics(v, &pv)
 		} else {
 			publishVolumeMetrics(v, nil)
 		}
 	}
-	return true, nil
 }
 
 // publishVolumeMetrics extracts data from a volume and exposes the metrics via prometheus