Add lastPublishedTime metric in PublishResources and relevant test

pkg/driver/dra_hooks.go

@@ -68,6 +68,8 @@ func (np *NetworkDriver) PublishResources(ctx context.Context) {
 			err := np.draPlugin.PublishResources(ctx, resources)
 			if err != nil {
 				klog.Error(err, "unexpected error trying to publish resources")
+			} else {
+				lastPublishedTime.SetToCurrentTime()
 			}
 		case <-ctx.Done():
 			klog.Error(ctx.Err(), "context canceled")

pkg/driver/dra_hooks_test.go

@@ -18,16 +18,17 @@ package driver
 
 import (
 	"context"
+	"fmt"
 	"strings"
 	"testing"
 
 	"github.com/google/dranet/pkg/apis"
-	"github.com/google/dranet/pkg/inventory"
 	"github.com/prometheus/client_golang/prometheus/testutil"
 	resourcev1 "k8s.io/api/resource/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/dynamic-resource-allocation/kubeletplugin"
+
 )
 
 func TestPublishResourcesPrometheusMetrics(t *testing.T) {
@@ -142,7 +143,7 @@ func TestPrepareResourceClaimsMetrics(t *testing.T) {
 		draPluginRequestsLatencySeconds.Reset()
 
 		np := &NetworkDriver{
-			netdb:      inventory.New(),
+			netdb:      newFakeInventoryDB(),
 			driverName: "test.driver",
 		}
 
@@ -239,3 +240,41 @@ func TestUnprepareResourceClaimsMetrics(t *testing.T) {
 		}
 	})
 }
+
+func TestPublishResourcesMetrics(t *testing.T) {
+	ctx, cancel := context.WithCancel(t.Context())
+	defer cancel()
+
+	fakeDraPlugin := newFakePluginHelper()
+	fakeNetDB := newFakeInventoryDB()
+
+	np := &NetworkDriver{
+		draPlugin: fakeDraPlugin,
+		netdb:     fakeNetDB,
+		nodeName:  "test-node",
+	}
+
+	go np.PublishResources(ctx)
+
+	t.Run("Success", func(t *testing.T) {
+		lastPublishedTime.Set(0)
+		fakeNetDB.resources <- []resourcev1.Device{}
+		<-fakeDraPlugin.publishCalled
+
+		if testutil.ToFloat64(lastPublishedTime) == 0 {
+			t.Errorf("lastPublishedTime should have been updated, but it is 0")
+		}
+	})
+
+	t.Run("Failure", func(t *testing.T) {
+		lastPublishedTime.Set(0)
+		fakeDraPlugin.publishErr = fmt.Errorf("mock publish error")
+		fakeNetDB.resources <- []resourcev1.Device{}
+		<-fakeDraPlugin.publishCalled
+
+		if testutil.ToFloat64(lastPublishedTime) != 0 {
+			t.Errorf("lastPublishedTime should not have been updated, but it is %f", testutil.ToFloat64(lastPublishedTime))
+		}
+	})
+}
+

pkg/driver/driver.go

@@ -30,10 +30,13 @@ import (
 	"github.com/containerd/nri/pkg/stub"
 	"github.com/vishvananda/netlink"
 
+	resourceapi "k8s.io/api/resource/v1"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/dynamic-resource-allocation/kubeletplugin"
+	"k8s.io/dynamic-resource-allocation/resourceslice"
 	"k8s.io/klog/v2"
+	registerapi "k8s.io/kubelet/pkg/apis/pluginregistration/v1"
 )
 
 const (
@@ -46,6 +49,23 @@ const (
 	maxAttempts = 5
 )
 
+// This interface is our internal contract for the behavior we need from a *kubeletplugin.Helper, created specifically so we can fake it in tests.
+type pluginHelper interface {
+	PublishResources(context.Context, resourceslice.DriverResources) error
+	Stop()
+	RegistrationStatus() *registerapi.RegistrationStatus
+}
+
+// This interface is our internal contract for the behavior we need from a *inventory.DB, created specifically so we can fake it in tests.
+type inventoryDB interface {
+	Run(context.Context) error
+	GetResources(context.Context) <-chan []resourceapi.Device
+	GetNetInterfaceName(string) (string, error)
+	AddPodNetNs(podKey string, netNs string)
+	RemovePodNetNs(podKey string)
+	GetPodNetNs(podKey string) (netNs string)
+}
+
 // WithFilter
 func WithFilter(filter cel.Program) Option {
 	return func(o *NetworkDriver) {
@@ -57,11 +77,11 @@ type NetworkDriver struct {
 	driverName string
 	nodeName   string
 	kubeClient kubernetes.Interface
-	draPlugin  *kubeletplugin.Helper
+	draPlugin  pluginHelper
 	nriPlugin  stub.Stub
 
 	// contains the host interfaces
-	netdb      *inventory.DB
+	netdb      inventoryDB
 	celProgram cel.Program
 
 	// Cache the rdma shared mode state

pkg/driver/driver_test.go

@@ -0,0 +1,67 @@
+package driver
+
+import (
+	"context"
+	resourcev1 "k8s.io/api/resource/v1"
+	"k8s.io/dynamic-resource-allocation/resourceslice"
+	registerapi "k8s.io/kubelet/pkg/apis/pluginregistration/v1"
+)
+
+// fakeDraPlugin is a mock implementation of the pluginHelper interface for testing.
+type fakePluginHelper struct {
+	publishErr         error
+	publishCalled      chan struct{}
+	registrationStatus *registerapi.RegistrationStatus
+}
+
+func newFakePluginHelper() *fakePluginHelper {
+	return &fakePluginHelper{
+		publishCalled: make(chan struct{}, 1),
+	}
+}
+
+func (m *fakePluginHelper) PublishResources(_ context.Context, _ resourceslice.DriverResources) error {
+	if m.publishCalled != nil {
+		m.publishCalled <- struct{}{}
+	}
+	return m.publishErr
+}
+
+func (m *fakePluginHelper) Stop() {}
+
+func (m *fakePluginHelper) RegistrationStatus() *registerapi.RegistrationStatus {
+	return m.registrationStatus
+}
+
+// mockNetDB is a mock implementation of the inventoryDB interface for testing.
+type fakeInventoryDB struct {
+	resources chan []resourcev1.Device
+	podNetNs  map[string]string
+}
+
+func newFakeInventoryDB() *fakeInventoryDB {
+	return &fakeInventoryDB{
+		resources: make(chan []resourcev1.Device, 1),
+		podNetNs:  make(map[string]string),
+	}
+}
+
+func (m *fakeInventoryDB) Run(_ context.Context) error { return nil }
+
+func (m *fakeInventoryDB) GetResources(_ context.Context) <-chan []resourcev1.Device {
+	return m.resources
+}
+
+func (m *fakeInventoryDB) GetNetInterfaceName(_ string) (string, error) { return "", nil }
+
+func (m *fakeInventoryDB) AddPodNetNs(podKey string, netNs string) {
+	m.podNetNs[podKey] = netNs
+}
+
+func (m *fakeInventoryDB) RemovePodNetNs(podKey string) {
+	delete(m.podNetNs, podKey)
+}
+
+func (m *fakeInventoryDB) GetPodNetNs(podKey string) string {
+	return m.podNetNs[podKey]
+}

pkg/driver/metrics.go

@@ -45,6 +45,7 @@ func registerMetrics() {
 		prometheus.MustRegister(nriPluginRequestsTotal)
 		prometheus.MustRegister(nriPluginRequestsLatencySeconds)
 		prometheus.MustRegister(publishedDevicesTotal)
+		prometheus.MustRegister(lastPublishedTime)
 	})
 }
 
@@ -79,5 +80,10 @@ var (
 		Name:      "published_devices_total",
 		Help:      "Total number of published devices.",
 	}, []string{"feature"})
+	lastPublishedTime = prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace: "dranet",
+		Subsystem: "driver",
+		Name:      "last_published_time_seconds",
+		Help:      "The timestamp of the last successful resource publication.",
+	})
 )
-