Add E2E test for Locality Load Balancing

test/e2e/locality_lb_test.go

@@ -0,0 +1,289 @@
+//go:build integ
+// +build integ
+
+/*
+ * Copyright The Kmesh 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 kmesh
+
+import (
+	"os"
+	"strings"
+	"testing"
+	"time"
+
+	"istio.io/istio/pkg/test/framework"
+	"istio.io/istio/pkg/test/shell"
+	"istio.io/istio/pkg/test/util/retry"
+)
+
+// applyManifest writes the provided manifest into a temporary file and applies it using kubectl.
+func applyManifest(ns, manifest string) error {
+	tmpFile, err := os.CreateTemp("", "manifest-*.yaml")
+	if err != nil {
+		return err
+	}
+	// Ensure the temporary file is removed after use.
+	defer os.Remove(tmpFile.Name())
+
+	// Write the manifest to the temporary file.
+	if _, err := tmpFile.WriteString(manifest); err != nil {
+		tmpFile.Close()
+		return err
+	}
+	tmpFile.Close()
+
+	cmd := "kubectl apply -n " + ns + " -f " + tmpFile.Name()
+	_, err = shell.Execute(true, cmd)
+	return err
+}
+
+func TestLocalityLoadBalancing(t *testing.T) {
+	// Declare err at the beginning so it can be reused throughout the test.
+	var err error
+
+	framework.NewTest(t).Run(func(t framework.TestContext) {
+		const ns = "sample"
+
+		// Create the test namespace "sample". Log but ignore errors if it already exists.
+		if _, err := shell.Execute(true, "kubectl create namespace "+ns); err != nil {
+			t.Logf("Namespace %s might already exist: %v", ns, err)
+		}
+
+		// Apply the Service manifest with PreferClose load balancing.
+		serviceYAML := `
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+spec:
+  ports:
+  - port: 5000
+    name: http
+  selector:
+    app: helloworld
+  trafficDistribution: PreferClose
+`
+		if err = applyManifest(ns, serviceYAML); err != nil {
+			t.Fatalf("Failed to apply Service manifest: %v", err)
+		}
+
+		// Deploy three helloworld instances with specific localities.
+		// Instance 1: Local instance on ambient-worker with version region.zone1.subzone1.
+		dep1 := `
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-region-zone1-subzone1
+  labels:
+    app: helloworld
+    version: region.zone1.subzone1
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: region.zone1.subzone1
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: region.zone1.subzone1
+    spec:
+      containers:
+      - name: helloworld
+        env:
+        - name: SERVICE_VERSION
+          value: region.zone1.subzone1
+        image: docker.io/istio/examples-helloworld-v1
+        imagePullPolicy: IfNotPresent
+        ports:
+        - containerPort: 5000
+      nodeSelector:
+        kubernetes.io/hostname: ambient-worker
+`
+		if err = applyManifest(ns, dep1); err != nil {
+			t.Fatalf("Failed to deploy dep1: %v", err)
+		}
+
+		// Instance 2: Remote instance on ambient-worker2 with version region.zone1.subzone2.
+		dep2 := `
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-region-zone1-subzone2
+  labels:
+    app: helloworld
+    version: region.zone1.subzone2
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: region.zone1.subzone2
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: region.zone1.subzone2
+    spec:
+      containers:
+      - name: helloworld
+        env:
+        - name: SERVICE_VERSION
+          value: region.zone1.subzone2
+        image: docker.io/istio/examples-helloworld-v1
+        imagePullPolicy: IfNotPresent
+        ports:
+        - containerPort: 5000
+      nodeSelector:
+        kubernetes.io/hostname: ambient-worker2
+`
+		if err = applyManifest(ns, dep2); err != nil {
+			t.Fatalf("Failed to deploy dep2: %v", err)
+		}
+
+		// Instance 3: Remote instance on ambient-worker3 with version region.zone2.subzone3.
+		dep3 := `
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-region-zone2-subzone3
+  labels:
+    app: helloworld
+    version: region.zone2.subzone3
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: region.zone2.subzone3
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: region.zone2.subzone3
+    spec:
+      containers:
+      - name: helloworld
+        env:
+        - name: SERVICE_VERSION
+          value: region.zone2.subzone3
+        image: docker.io/istio/examples-helloworld-v1
+        imagePullPolicy: IfNotPresent
+        ports:
+        - containerPort: 5000
+      nodeSelector:
+        kubernetes.io/hostname: ambient-worker3
+`
+		if err = applyManifest(ns, dep3); err != nil {
+			t.Fatalf("Failed to deploy dep3: %v", err)
+		}
+
+		// Deploy a sleep client on ambient-worker.
+		clientDep := `
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: sleep
+  labels:
+    app: sleep
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: sleep
+  template:
+    metadata:
+      labels:
+        app: sleep
+    spec:
+      containers:
+      - name: sleep
+        image: curlimages/curl
+        command: ["/bin/sleep", "infinity"]
+        imagePullPolicy: IfNotPresent
+      nodeSelector:
+        kubernetes.io/hostname: ambient-worker
+`
+		if err = applyManifest(ns, clientDep); err != nil {
+			t.Fatalf("Failed to deploy sleep client: %v", err)
+		}
+
+		// Wait for all deployments to be available.
+		deployments := []string{
+			"helloworld-region-zone1-subzone1",
+			"helloworld-region-zone1-subzone2",
+			"helloworld-region-zone2-subzone3",
+			"sleep",
+		}
+		for _, dep := range deployments {
+			cmd := "kubectl wait --for=condition=available deployment/" + dep + " -n " + ns + " --timeout=120s"
+			if _, err := shell.Execute(true, cmd); err != nil {
+				t.Fatalf("Deployment %s not ready: %v", dep, err)
+			}
+		}
+
+		// Test Locality Preferred:
+		// From the sleep client, access the helloworld service and expect a response from the local instance (dep1).
+		t.Log("Testing locality preferred (expect response from region.zone1.subzone1)...")
+		var localResponse string
+		err = retry.Until(func() bool {
+			out, execErr := shell.Execute(true, "kubectl exec -n "+ns+" $(kubectl get pod -n "+ns+" -l app=sleep -o jsonpath='{.items[0].metadata.name}') -c sleep -- curl -sSL http://helloworld:5000/hello")
+			if execErr != nil {
+				t.Logf("Curl error: %v", execErr)
+				return false
+			}
+			t.Logf("Curl output: %s", out)
+			if strings.Contains(out, "region.zone1.subzone1") {
+				localResponse = out
+				return true
+			}
+			return false
+		}, retry.Timeout(60*time.Second), retry.Delay(2*time.Second))
+		if err != nil {
+			t.Fatalf("Locality preferred test failed: expected response from region.zone1.subzone1, got: %s", localResponse)
+		}
+		t.Log("Locality preferred test passed.")
+
+		// Test Locality Failover:
+		// Delete the local deployment (dep1) and expect traffic to fail over to the remote instance (dep2).
+		t.Log("Testing locality failover (expect response from region.zone1.subzone2)...")
+		if _, err := shell.Execute(true, "kubectl delete deployment helloworld-region-zone1-subzone1 -n "+ns); err != nil {
+			t.Fatalf("Failed to delete local deployment: %v", err)
+		}
+		var failoverResponse string
+		err = retry.Until(func() bool {
+			out, execErr := shell.Execute(true, "kubectl exec -n "+ns+" $(kubectl get pod -n "+ns+" -l app=sleep -o jsonpath='{.items[0].metadata.name}') -c sleep -- curl -sSL http://helloworld:5000/hello")
+			if execErr != nil {
+				t.Logf("Curl error after failover: %v", execErr)
+				return false
+			}
+			t.Logf("Curl output after failover: %s", out)
+			if strings.Contains(out, "region.zone1.subzone2") {
+				failoverResponse = out
+				return true
+			}
+			return false
+		}, retry.Timeout(60*time.Second), retry.Delay(2*time.Second))
+		if err != nil {
+			t.Fatalf("Locality failover test failed: expected response from region.zone1.subzone2, got: %s", failoverResponse)
+		}
+		t.Log("Locality failover test passed.")
+	})
+}