[IPAM]: added unit tests for sync routine

pkg/ipam/ipam_suite_test.go

@@ -0,0 +1,43 @@
+// Copyright 2019-2024 The Liqo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ipam
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	corev1 "k8s.io/api/core/v1"
+	"k8s.io/client-go/kubernetes/scheme"
+
+	liqov1beta1 "github.com/liqotech/liqo/apis/core/v1beta1"
+	ipamv1alpha1 "github.com/liqotech/liqo/apis/ipam/v1alpha1"
+	networkingv1beta1 "github.com/liqotech/liqo/apis/networking/v1beta1"
+	"github.com/liqotech/liqo/pkg/utils/testutil"
+)
+
+func TestIpam(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Ipam Suite")
+}
+
+var _ = BeforeSuite(func() {
+	testutil.LogsToGinkgoWriter()
+
+	Expect(corev1.AddToScheme(scheme.Scheme)).To(Succeed())
+	Expect(liqov1beta1.AddToScheme(scheme.Scheme)).To(Succeed())
+	Expect(networkingv1beta1.AddToScheme(scheme.Scheme)).To(Succeed())
+	Expect(ipamv1alpha1.AddToScheme(scheme.Scheme)).To(Succeed())
+})

pkg/ipam/sync.go

@@ -55,20 +55,27 @@ func (lipam *LiqoIPAM) sync(ctx context.Context, syncFrequency time.Duration) {
 
 func (lipam *LiqoIPAM) syncNetworks(ctx context.Context, expiredThreshold time.Time) error {
 	// List all networks present in the cluster.
-	nets, err := listNetworksOnCluster(ctx, lipam.Client)
+	clusterNetworks, err := listNetworksOnCluster(ctx, lipam.Client)
 	if err != nil {
 		return err
 	}
 
-	// Create a set for faster lookup.
-	nwSet := make(map[string]struct{})
-	for _, net := range nets {
-		nwSet[net] = struct{}{}
+	// Create the set of networks present in the cluster (for faster lookup later).
+	setClusterNetworks := make(map[string]struct{})
+
+	// Add networks that are present in the cluster but not in the cache.
+	for _, net := range clusterNetworks {
+		if _, inCache := lipam.cacheNetworks[net]; !inCache {
+			if err := lipam.reserveNetwork(net); err != nil {
+				return err
+			}
+		}
+		setClusterNetworks[net] = struct{}{} // add network to the set
 	}
 
 	// Remove networks that are present in the cache but not in the cluster, and were added before the threshold.
 	for key := range lipam.cacheNetworks {
-		if _, ok := nwSet[key]; !ok && lipam.cacheNetworks[key].creationTimestamp.Before(expiredThreshold) {
+		if _, inCluster := setClusterNetworks[key]; !inCluster && lipam.cacheNetworks[key].creationTimestamp.Before(expiredThreshold) {
 			lipam.freeNetwork(lipam.cacheNetworks[key].cidr)
 		}
 	}
@@ -83,15 +90,22 @@ func (lipam *LiqoIPAM) syncIPs(ctx context.Context, expiredThreshold time.Time)
 		return err
 	}
 
-	// Create a set for faster lookup.
-	ipSet := make(map[string]struct{})
+	// Create the set of IPs present in the cluster (for faster lookup later).
+	setClusterIPs := make(map[string]struct{})
+
+	// Add IPs that are present in the cluster but not in the cache.
 	for _, ip := range ips {
-		ipSet[ip.String()] = struct{}{}
+		if _, inCache := lipam.cacheIPs[ip.String()]; !inCache {
+			if err := lipam.reserveIP(ip); err != nil {
+				return err
+			}
+		}
+		setClusterIPs[ip.String()] = struct{}{} // add IP to the set
 	}
 
 	// Remove IPs that are present in the cache but not in the cluster, and were added before the threshold.
 	for key := range lipam.cacheIPs {
-		if _, ok := ipSet[key]; !ok && lipam.cacheIPs[key].creationTimestamp.Before(expiredThreshold) {
+		if _, inCluster := setClusterIPs[key]; !inCluster && lipam.cacheIPs[key].creationTimestamp.Before(expiredThreshold) {
 			lipam.freeIP(lipam.cacheIPs[key].ipCidr)
 		}
 	}

pkg/ipam/sync_test.go

@@ -0,0 +1,175 @@
+// Copyright 2019-2024 The Liqo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ipam
+
+import (
+	"context"
+	"time"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes/scheme"
+	"k8s.io/utils/ptr"
+	"sigs.k8s.io/controller-runtime/pkg/client/fake"
+
+	ipamv1alpha1 "github.com/liqotech/liqo/apis/ipam/v1alpha1"
+	networkingv1beta1 "github.com/liqotech/liqo/apis/networking/v1beta1"
+)
+
+var _ = Describe("Sync routine tests", func() {
+	const (
+		syncFrequency = 3 * time.Second
+		testNamespace = "test"
+	)
+
+	var (
+		ctx               context.Context
+		fakeClientBuilder *fake.ClientBuilder
+		now               time.Time
+		newEntryThreshold time.Time
+		notNewTimestamp   time.Time
+
+		fakeIpamServer *LiqoIPAM
+
+		addNetowrkToCache = func(ipamServer *LiqoIPAM, cidr string, creationTimestamp time.Time) {
+			ipamServer.cacheNetworks[cidr] = networkInfo{
+				cidr:              cidr,
+				creationTimestamp: creationTimestamp,
+			}
+		}
+
+		addIPToCache = func(ipamServer *LiqoIPAM, ip, cidr string, creationTimestamp time.Time) {
+			ipC := ipCidr{ip: ip, cidr: cidr}
+			ipamServer.cacheIPs[ipC.String()] = ipInfo{
+				ipCidr:            ipC,
+				creationTimestamp: creationTimestamp,
+			}
+		}
+
+		newNetwork = func(name, cidr string) *ipamv1alpha1.Network {
+			return &ipamv1alpha1.Network{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      name,
+					Namespace: testNamespace,
+				},
+				Spec: ipamv1alpha1.NetworkSpec{
+					CIDR: networkingv1beta1.CIDR(cidr),
+				},
+				Status: ipamv1alpha1.NetworkStatus{
+					CIDR: networkingv1beta1.CIDR(cidr),
+				},
+			}
+		}
+
+		newIP = func(name, ip, cidr string) *ipamv1alpha1.IP {
+			return &ipamv1alpha1.IP{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      name,
+					Namespace: testNamespace,
+				},
+				Spec: ipamv1alpha1.IPSpec{
+					IP:   networkingv1beta1.IP(ip),
+					CIDR: ptr.To(networkingv1beta1.CIDR(cidr)),
+				},
+				Status: ipamv1alpha1.IPStatus{
+					IP:   networkingv1beta1.IP(ip),
+					CIDR: networkingv1beta1.CIDR(cidr),
+				},
+			}
+		}
+	)
+
+	BeforeEach(func() {
+		ctx = context.Background()
+		fakeClientBuilder = fake.NewClientBuilder().WithScheme(scheme.Scheme)
+		now = time.Now()
+		newEntryThreshold = now.Add(-syncFrequency)
+		notNewTimestamp = newEntryThreshold.Add(-time.Minute)
+	})
+
+	Describe("Testing the sync routine", func() {
+		Context("Sync Networks", func() {
+			BeforeEach(func() {
+				// Add in-cluster networks
+				client := fakeClientBuilder.WithObjects(
+					newNetwork("net1", "10.0.0.0/16"),
+					newNetwork("net2", "10.1.0.0/16"),
+					newNetwork("net3", "10.2.0.0/16"),
+				).Build()
+
+				// Populate the cache
+				fakeIpamServer = &LiqoIPAM{
+					Client:        client,
+					cacheNetworks: make(map[string]networkInfo),
+				}
+				addNetowrkToCache(fakeIpamServer, "10.0.0.0/16", now)
+				addNetowrkToCache(fakeIpamServer, "10.1.0.0/16", notNewTimestamp)
+				addNetowrkToCache(fakeIpamServer, "10.3.0.0/16", notNewTimestamp)
+				addNetowrkToCache(fakeIpamServer, "10.4.0.0/16", now)
+			})
+
+			It("should remove networks from cache if they are not present in the cluster", func() {
+				// Run sync
+				Expect(fakeIpamServer.syncNetworks(ctx, newEntryThreshold)).To(Succeed())
+
+				// Check the cache
+				Expect(fakeIpamServer.cacheNetworks).To(HaveKey("10.0.0.0/16"))    // network in cluster and cache
+				Expect(fakeIpamServer.cacheNetworks).To(HaveKey("10.1.0.0/16"))    // network in cluster and cache before new entry threshold
+				Expect(fakeIpamServer.cacheNetworks).To(HaveKey("10.2.0.0/16"))    // network in cluster but not in cache
+				Expect(fakeIpamServer.cacheNetworks).NotTo(HaveKey("10.3.0.0/16")) // network not in cluster but in cache before new entry threshold
+				Expect(fakeIpamServer.cacheNetworks).To(HaveKey("10.4.0.0/16"))    // network not in cluster but in cache after new entry threshold
+			})
+		})
+
+		Context("Sync IPs", func() {
+			BeforeEach(func() {
+				// Add in-cluster IPs
+				client := fakeClientBuilder.WithObjects(
+					newIP("ip1", "10.0.0.0", "10.0.0.0/24"),
+					newIP("ip2", "10.0.0.1", "10.0.0.0/24"),
+					newIP("ip3", "10.0.0.2", "10.0.0.0/24"),
+				).Build()
+
+				// Populate the cache
+				fakeIpamServer = &LiqoIPAM{
+					Client:   client,
+					cacheIPs: make(map[string]ipInfo),
+				}
+				addIPToCache(fakeIpamServer, "10.0.0.0", "10.0.0.0/24", now)
+				addIPToCache(fakeIpamServer, "10.0.0.1", "10.0.0.0/24", notNewTimestamp)
+				addIPToCache(fakeIpamServer, "10.0.0.3", "10.0.0.0/24", notNewTimestamp)
+				addIPToCache(fakeIpamServer, "10.0.0.4", "10.0.0.0/24", now)
+			})
+
+			It("should remove IPs from cache if they are not present in the cluster", func() {
+				// Run sync
+				Expect(fakeIpamServer.syncIPs(ctx, newEntryThreshold)).To(Succeed())
+
+				// Check the cache
+				Expect(fakeIpamServer.cacheIPs).To(HaveKey(
+					ipCidr{ip: "10.0.0.0", cidr: "10.0.0.0/24"}.String())) // IP in cluster and cache
+				Expect(fakeIpamServer.cacheIPs).To(HaveKey(
+					ipCidr{ip: "10.0.0.1", cidr: "10.0.0.0/24"}.String())) // IP in cluster and cache before new entry threshold
+				Expect(fakeIpamServer.cacheIPs).To(HaveKey(
+					ipCidr{ip: "10.0.0.2", cidr: "10.0.0.0/24"}.String())) // IP in cluster but not in cache
+				Expect(fakeIpamServer.cacheIPs).NotTo(HaveKey(
+					ipCidr{ip: "10.0.0.3", cidr: "10.0.0.0/24"}.String())) // IP not in cluster but in cache before new entry threshold
+				Expect(fakeIpamServer.cacheIPs).To(HaveKey(
+					ipCidr{ip: "10.0.0.4", cidr: "10.0.0.0/24"}.String())) // IP not in cluster but in cache after new entry threshold
+			})
+		})
+	})
+})