feat: support adding annotation to hold agent upgrade

Signed-off-by: Zespre Chang <zespre.chang@suse.com>

pkg/controller/ippool/common.go

@@ -191,6 +191,14 @@ func NewIPPoolBuilder(namespace, name string) *IPPoolBuilder {
 	}
 }
 
+func (b *IPPoolBuilder) Annotation(key, value string) *IPPoolBuilder {
+	if b.ipPool.Annotations == nil {
+		b.ipPool.Annotations = make(map[string]string)
+	}
+	b.ipPool.Annotations[key] = value
+	return b
+}
+
 func (b *IPPoolBuilder) NetworkName(networkName string) *IPPoolBuilder {
 	b.ipPool.Spec.NetworkName = networkName
 	return b

pkg/controller/ippool/controller.go

@@ -29,7 +29,8 @@ import (
 const (
 	controllerName = "vm-dhcp-ippool-controller"
 
-	multusNetworksAnnotationKey = "k8s.v1.cni.cncf.io/networks"
+	multusNetworksAnnotationKey         = "k8s.v1.cni.cncf.io/networks"
+	holdIPPoolAgentUpgradeAnnotationKey = "network.harvesterhci.io/hold-ippool-agent-upgrade"
 
 	ipPoolNamespaceLabelKey  = network.GroupName + "/ippool-namespace"
 	ipPoolNameLabelKey       = network.GroupName + "/ippool-name"
@@ -281,8 +282,7 @@ func (h *Handler) DeployAgent(ipPool *networkv1.IPPool, status networkv1.IPPoolS
 	}
 
 	if ipPool.Status.AgentPodRef != nil {
-		status.AgentPodRef.Image = h.agentImage.String()
-
+		status.AgentPodRef.Image = h.getAgentImage(ipPool)
 		pod, err := h.podCache.Get(ipPool.Status.AgentPodRef.Namespace, ipPool.Status.AgentPodRef.Name)
 		if err != nil {
 			if !apierrors.IsNotFound(err) {
@@ -434,6 +434,14 @@ func isPodReady(pod *corev1.Pod) bool {
 	return false
 }
 
+func (h *Handler) getAgentImage(ipPool *networkv1.IPPool) string {
+	_, ok := ipPool.Annotations[holdIPPoolAgentUpgradeAnnotationKey]
+	if ok {
+		return ipPool.Status.AgentPodRef.Image
+	}
+	return h.agentImage.String()
+}
+
 func (h *Handler) cleanup(ipPool *networkv1.IPPool) error {
 	if ipPool.Status.AgentPodRef == nil {
 		return nil

pkg/controller/ippool/controller_test.go

@@ -555,6 +555,64 @@ func TestHandler_DeployAgent(t *testing.T) {
 		assert.Equal(t, expectedStatus, status)
 	})
 
+	t.Run("agent pod upgrade held back", func(t *testing.T) {
+		givenIPPool := newTestIPPoolBuilder().
+			Annotation(holdIPPoolAgentUpgradeAnnotationKey, "true").
+			ServerIP(testServerIP).
+			CIDR(testCIDR).
+			NetworkName(testNetworkName).
+			AgentPodRef(testPodNamespace, testPodName, testImage, "").Build()
+		givenNAD := newTestNetworkAttachmentDefinitionBuilder().
+			Label(clusterNetworkLabelKey, testClusterNetwork).Build()
+		givenPod, _ := prepareAgentPod(
+			NewIPPoolBuilder(testIPPoolNamespace, testIPPoolName).
+				ServerIP(testServerIP).
+				CIDR(testCIDR).
+				NetworkName(testNetworkName).Build(),
+			false,
+			testPodNamespace,
+			testClusterNetwork,
+			testServiceAccountName,
+			&config.Image{
+				Repository: testImageRepository,
+				Tag:        testImageTag,
+			},
+		)
+
+		expectedStatus := newTestIPPoolStatusBuilder().
+			AgentPodRef(testPodNamespace, testPodName, testImage, "").Build()
+
+		nadGVR := schema.GroupVersionResource{
+			Group:    "k8s.cni.cncf.io",
+			Version:  "v1",
+			Resource: "network-attachment-definitions",
+		}
+
+		clientset := fake.NewSimpleClientset()
+		err := clientset.Tracker().Create(nadGVR, givenNAD, givenNAD.Namespace)
+		assert.Nil(t, err, "mock resource should add into fake controller tracker")
+
+		k8sclientset := k8sfake.NewSimpleClientset()
+		err = k8sclientset.Tracker().Add(givenPod)
+		assert.Nil(t, err, "mock resource should add into fake controller tracker")
+
+		handler := Handler{
+			agentNamespace: testPodNamespace,
+			agentImage: &config.Image{
+				Repository: testImageRepository,
+				Tag:        testImageTagNew,
+			},
+			agentServiceAccountName: testServiceAccountName,
+			nadCache:                fakeclient.NetworkAttachmentDefinitionCache(clientset.K8sCniCncfIoV1().NetworkAttachmentDefinitions),
+			podClient:               fakeclient.PodClient(k8sclientset.CoreV1().Pods),
+			podCache:                fakeclient.PodCache(k8sclientset.CoreV1().Pods),
+		}
+
+		status, err := handler.DeployAgent(givenIPPool, givenIPPool.Status)
+		assert.Nil(t, err)
+		assert.Equal(t, expectedStatus, status)
+	})
+
 	t.Run("existing agent pod uid mismatch", func(t *testing.T) {
 		givenIPPool := newTestIPPoolBuilder().
 			ServerIP(testServerIP).