Add integration tests for DNS AUTO ALLOCATION

Signed-off-by: Yann Liu <yannliu@redhat.com>

tests/integration/pilot/dnsautoallocation/main_test.go

@@ -0,0 +1,56 @@
+//go:build integ
+// +build integ
+
+//  Copyright Istio 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 dnsautoallocation
+
+import (
+	"testing"
+
+	"istio.io/istio/pkg/test/framework"
+	"istio.io/istio/pkg/test/framework/components/echo/common/deployment"
+	"istio.io/istio/pkg/test/framework/components/istio"
+	"istio.io/istio/pkg/test/framework/label"
+	"istio.io/istio/pkg/test/framework/resource"
+)
+
+var (
+	i istio.Instance
+
+	// Below are various preconfigured echo deployments. Whenever possible, tests should utilize these
+	// to avoid excessive creation/tear down of deployments. In general, a test should only deploy echo if
+	// its doing something unique to that specific test.
+	apps = deployment.SingleNamespaceView{}
+)
+
+func TestMain(m *testing.M) {
+	// nolint: staticcheck
+	framework.
+		NewSuite(m).
+		// Requires custom CP installations. Consider merging into pilot/revisions
+		Label(label.CustomSetup).
+		Setup(istio.Setup(&i, func(_ resource.Context, cfg *istio.Config) {
+			cfg.ControlPlaneValues = `
+meshConfig:
+  defaultConfig:
+    proxyMetadata:
+      ISTIO_META_DNS_CAPTURE: "true"
+      ISTIO_META_DNS_AUTO_ALLOCATE: "true"
+`
+		})).
+		Setup(deployment.SetupSingleNamespace(&apps, deployment.Config{})).
+		Run()
+}

tests/integration/pilot/dnsautoallocation/mesh_external_service_entry_test.go

@@ -0,0 +1,130 @@
+//go:build integ
+// +build integ
+
+//  Copyright Istio 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 dnsautoallocation
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+	"time"
+
+	"istio.io/istio/pkg/config/protocol"
+	"istio.io/istio/pkg/test/framework"
+	"istio.io/istio/pkg/test/framework/components/echo"
+	"istio.io/istio/pkg/test/framework/components/echo/common/ports"
+	"istio.io/istio/pkg/test/util/retry"
+)
+
+type testRequestSpec struct {
+	protocol   protocol.Instance
+	portName   string
+	portNumber int
+}
+
+var requestsSpec = []testRequestSpec{
+	{
+		portNumber: 80,
+		portName:   ports.HTTP,
+		protocol:   protocol.HTTP,
+	},
+	{
+		portNumber: 443,
+		portName:   ports.HTTPS,
+		protocol:   protocol.HTTPS,
+	},
+}
+
+const serviceEntryFile = "testdata/service-entry-tmpl.yaml"
+const externalHost = "istio.io"
+
+func TestMeshExternalServiceEntry(t *testing.T) {
+	// nolint: staticcheck
+	framework.
+		NewTest(t).
+		Features("traffic.dnscautoallocation").
+		Run(func(ctx framework.TestContext) {
+			meshNs := apps.A.NamespaceName()
+			client := apps.A[0]
+			server := apps.External.All[0]
+			// externalHost := server.ClusterLocalFQDN()
+
+			testRequest(ctx, "without-applying-any-service-entry", client, server)
+
+			httpSe := ctx.ConfigIstio().EvalFile(meshNs, map[string]interface{}{
+				"externalHost": externalHost,
+				"portNumber":   80,
+				"portName":     ports.HTTP,
+				"portProtocol": protocol.HTTP,
+			}, serviceEntryFile)
+
+			httpSe.ApplyOrFail(ctx)
+
+			// testRequest(ctx, "after-applying-only-http-service-entry", client, server)
+
+			httpsSe := ctx.ConfigIstio().EvalFile(meshNs, map[string]interface{}{
+				"externalHost": externalHost,
+				"portNumber":   443,
+				"portName":     ports.HTTPS,
+				"portProtocol": protocol.HTTPS,
+			}, serviceEntryFile)
+
+			httpsSe.ApplyOrFail(ctx)
+
+			testRequest(ctx, "after-applying-both-https-and-http-service-entry", client, server)
+		})
+}
+
+func testRequest(ctx framework.TestContext, status string, client, server echo.Instance) {
+	for _, spec := range requestsSpec {
+		testName := fmt.Sprintf("%s-request-%s", spec.portName, status)
+
+		ctx.NewSubTest(testName).Run(func(ctx framework.TestContext) {
+			retry.UntilSuccessOrFail(ctx, func() error {
+
+				if err := testConnectivity(client, server, spec.protocol, spec.portName, spec.portNumber, testName); err != nil {
+					return err
+				}
+
+				return nil
+			}, retry.Timeout(10*time.Second))
+		})
+	}
+}
+
+func testConnectivity(from, to echo.Instance, p protocol.Instance, portName string, portNumber int, testName string) error {
+	res, err := from.Call(echo.CallOptions{
+		Address: externalHost,
+		Port: echo.Port{
+			ServicePort: portNumber,
+			Name:        portName,
+			Protocol:    p,
+		},
+	})
+
+	if err != nil {
+		return fmt.Errorf("failed to request to external service: %s", err)
+	}
+
+	code, err := strconv.Atoi(res.Responses[0].Code)
+
+	if err == nil && code >= 500 {
+		return fmt.Errorf("expected to get server status code, got: %s", res.Responses[0].Code)
+	}
+
+	return nil
+}

tests/integration/pilot/dnsautoallocation/testdata/service-entry-tmpl.yaml

@@ -0,0 +1,13 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: ServiceEntry
+metadata:
+  name: {{ .portName }}-external-se
+spec:
+  hosts:
+  - {{ .externalHost }}
+  location: MESH_EXTERNAL
+  ports:
+  - number: {{ .portNumber }}
+    name: {{ .portName }}
+    protocol: {{ .portProtocol }}
+  resolution: DNS