conformance tests for percentage-based request mirroring

conformance/tests/httproute-request-mirror.go

@@ -57,10 +57,14 @@ var HTTPRouteRequestMirror = suite.ConformanceTest{
 },
 },
 Backend: "infra-backend-v1",
-MirroredTo: []http.BackendRef{{
-Name: "infra-backend-v2",
-Namespace: ns,
-}},
+MirroredTo: []http.MirroredBackend{
+{
+BackendRef: http.BackendRef{
+Name: "infra-backend-v2",
+Namespace: ns,
+},
+},
+},
 Namespace: ns,
 },
 {
@@ -84,10 +88,14 @@ var HTTPRouteRequestMirror = suite.ConformanceTest{
 },
 Namespace: ns,
 Backend: "infra-backend-v1",
-MirroredTo: []http.BackendRef{{
-Name: "infra-backend-v2",
-Namespace: ns,
-}},
+MirroredTo: []http.MirroredBackend{
+{
+BackendRef: http.BackendRef{
+Name: "infra-backend-v2",
+Namespace: ns,
+},
+},
+},
 },
 }
 for i := range testCases {

conformance/tests/httproute-request-multiple-mirrors.go

@@ -58,14 +58,18 @@ var HTTPRouteRequestMultipleMirrors = suite.ConformanceTest{
 },
 },
 Backend: "infra-backend-v1",
-MirroredTo: []http.BackendRef{
+MirroredTo: []http.MirroredBackend{
 {
-Name: "infra-backend-v2",
-Namespace: ns,
+BackendRef: http.BackendRef{
+Name: "infra-backend-v2",
+Namespace: ns,
+},
 },
 {
-Name: "infra-backend-v3",
-Namespace: ns,
+BackendRef: http.BackendRef{
+Name: "infra-backend-v3",
+Namespace: ns,
+},
 },
 },
 Namespace: ns,
@@ -90,14 +94,18 @@ var HTTPRouteRequestMultipleMirrors = suite.ConformanceTest{
 },
 Namespace: ns,
 Backend: "infra-backend-v1",
-MirroredTo: []http.BackendRef{
+MirroredTo: []http.MirroredBackend{
 {
-Name: "infra-backend-v2",
-Namespace: ns,
+BackendRef: http.BackendRef{
+Name: "infra-backend-v2",
+Namespace: ns,
+},
 },
 {
-Name: "infra-backend-v3",
-Namespace: ns,
+BackendRef: http.BackendRef{
+Name: "infra-backend-v3",
+Namespace: ns,
+},
 },
 },
 },

conformance/tests/httproute-request-percentage-mirror.go

@@ -0,0 +1,236 @@
+/*
+Copyright 2025 The Kubernetes 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 tests
+
+import (
+"errors"
+"fmt"
+"regexp"
+"sync"
+"testing"
+"time"
+
+"github.com/stretchr/testify/require"
+"k8s.io/apimachinery/pkg/types"
+"k8s.io/utils/ptr"
+
+"sigs.k8s.io/gateway-api/conformance/utils/config"
+"sigs.k8s.io/gateway-api/conformance/utils/http"
+"sigs.k8s.io/gateway-api/conformance/utils/kubernetes"
+"sigs.k8s.io/gateway-api/conformance/utils/roundtripper"
+"sigs.k8s.io/gateway-api/conformance/utils/suite"
+"sigs.k8s.io/gateway-api/conformance/utils/tlog"
+"sigs.k8s.io/gateway-api/pkg/features"
+)
+
+const (
+concurrentRequests = 10
+tolerancePercentage = 5.0
+totalRequests = 500.0
+numDistributionChecks = 5
+)
+
+func init() {
+ConformanceTests = append(ConformanceTests, HTTPRouteRequestPercentageMirror)
+}
+
+var HTTPRouteRequestPercentageMirror = suite.ConformanceTest{
+ShortName: "HTTPRouteRequestPercentageMirror",
+Description: "An HTTPRoute with percentage based request mirroring",
+Manifests: []string{"tests/httproute-request-percentage-mirror.yaml"},
+Features: []features.FeatureName{
+features.SupportGateway,
+features.SupportHTTPRoute,
+features.SupportHTTPRouteRequestPercentageMirror,
+},
+Provisional: true,
+Test: func(t *testing.T, suite *suite.ConformanceTestSuite) {
+var (
+ns = "gateway-conformance-infra"
+routeNN = types.NamespacedName{Name: "request-percentage-mirror", Namespace: ns}
+gwNN = types.NamespacedName{Name: "same-namespace", Namespace: ns}
+gwAddr = kubernetes.GatewayAndHTTPRoutesMustBeAccepted(t, suite.Client, suite.TimeoutConfig, suite.ControllerName, kubernetes.NewGatewayRef(gwNN), routeNN)
+)
+
+kubernetes.HTTPRouteMustHaveResolvedRefsConditionsTrue(t, suite.Client, suite.TimeoutConfig, routeNN, gwNN)
+
+testCases := []http.ExpectedResponse{
+{
+Request: http.Request{Path: "/percent-mirror"},
+Namespace: ns,
+ExpectedRequest: &http.ExpectedRequest{
+Request: http.Request{
+Path: "/percent-mirror",
+},
+},
+Backend: "infra-backend-v1",
+MirroredTo: []http.MirroredBackend{
+{
+BackendRef: http.BackendRef{
+Name: "infra-backend-v2",
+Namespace: ns,
+},
+Percent: ptr.To(int32(20)),
+},
+},
+}, {
+Request: http.Request{Path: "/percent-mirror-fraction"},
+Namespace: ns,
+ExpectedRequest: &http.ExpectedRequest{
+Request: http.Request{
+Path: "/percent-mirror-fraction",
+},
+},
+Backend: "infra-backend-v1",
+MirroredTo: []http.MirroredBackend{
+{
+BackendRef: http.BackendRef{
+Name: "infra-backend-v2",
+Namespace: ns,
+},
+Percent: ptr.To(int32(50)),
+},
+},
+}, {
+Request: http.Request{
+Path: "/percent-mirror-and-modify-headers",
+Headers: map[string]string{
+"X-Header-Remove": "remove-val",
+"X-Header-Add-Append": "append-val-1",
+},
+},
+ExpectedRequest: &http.ExpectedRequest{
+Request: http.Request{
+Path: "/percent-mirror-and-modify-headers",
+Headers: map[string]string{
+"X-Header-Add": "header-val-1",
+"X-Header-Add-Append": "append-val-1,header-val-2",
+"X-Header-Set": "set-overwrites-values",
+},
+},
+AbsentHeaders: []string{"X-Header-Remove"},
+},
+Namespace: ns,
+Backend: "infra-backend-v1",
+MirroredTo: []http.MirroredBackend{
+{
+BackendRef: http.BackendRef{
+Name: "infra-backend-v2",
+Namespace: ns,
+},
+Percent: ptr.To(int32(35)),
+},
+},
+},
+}
+
+for i := range testCases {
+expected := testCases[i]
+t.Run(expected.GetTestCaseName(i), func(t *testing.T) {
+// Assert request succeeds before doing our distribution check
+http.MakeRequestAndExpectEventuallyConsistentResponse(t, suite.RoundTripper, suite.TimeoutConfig, gwAddr, expected)
+
+// Override to not have more requests than expected
+var dedicatedTimeoutConfig config.TimeoutConfig
+dedicatedTimeoutConfig = suite.TimeoutConfig
+dedicatedTimeoutConfig.RequiredConsecutiveSuccesses = 1
+// used to limit number of parallel go routines
+semaphore := make(chan struct{}, concurrentRequests)
+var wg sync.WaitGroup
+
+for k := 0; k < numDistributionChecks; k++ {
+timeNow := time.Now()
+for j := 0; j < totalRequests; j++ {
+wg.Add(1)
+semaphore <- struct{}{}
+go func(t *testing.T, r roundtripper.RoundTripper, timeoutConfig config.TimeoutConfig, gwAddr string, expected http.ExpectedResponse) {
+defer wg.Done()
+defer func() { <-semaphore }()
+http.MakeRequestAndExpectEventuallyConsistentResponse(t, r, timeoutConfig, gwAddr, expected)
+}(t, suite.RoundTripper, dedicatedTimeoutConfig, gwAddr, expected)
+}
+wg.Wait()
+if err := testMirroredRequestsDistribution(t, suite, expected, timeNow); err != nil {
+t.Logf("Traffic distribution test failed (%d/%d): %s", k+1, numDistributionChecks, err)
+time.Sleep(2 * time.Second)
+} else {
+return
+}
+}
+t.Fatal("Percentage based mirror distribution tests failed")
+})
+}
+},
+}
+
+func testMirroredRequestsDistribution(t *testing.T, suite *suite.ConformanceTestSuite, expected http.ExpectedResponse, timeVal time.Time) error {
+mirrorPods := expected.MirroredTo
+for i, mirrorPod := range mirrorPods {
+if mirrorPod.Name == "" {
+tlog.Fatalf(t, "Mirrored BackendRef[%d].Name wasn't provided in the testcase, this test should only check http request mirror.", i)
+}
+}
+
+var mu sync.Mutex
+mirroredCounts := make(map[string]int)
+
+for _, mirrorPod := range mirrorPods {
+require.Eventually(t, func() bool {
+mirrorLogRegexp := regexp.MustCompile(fmt.Sprintf("Echoing back request made to \\%s to client", expected.Request.Path))
+
+tlog.Log(t, "Searching for the mirrored request log")
+tlog.Logf(t, `Reading "%s/%s" logs`, mirrorPod.Namespace, mirrorPod.Name)
+logs, err := kubernetes.DumpEchoLogs(mirrorPod.Namespace, mirrorPod.Name, suite.Client, suite.Clientset, timeVal)
+if err != nil {
+tlog.Logf(t, `Couldn't read "%s/%s" logs: %v`, mirrorPod.Namespace, mirrorPod.Name, err)
+return false
+}
+
+count := 0
+for _, log := range logs {
+if mirrorLogRegexp.MatchString(log) {
+count++
+}
+}
+mu.Lock()
+mirroredCounts[mirrorPod.Name] += count
+mu.Unlock()
+
+return true
+}, 60*time.Second, time.Millisecond*100, fmt.Sprintf(`Couldn't verify the logs for "%s/%s"`, mirrorPod.Namespace, mirrorPod.Name))
+}
+
+var errs []error
+
+for _, mirrorPod := range mirrorPods {
+expected := float64(totalRequests) * float64(*mirrorPod.Percent) / 100.0
+minExpected := expected * (1 - tolerancePercentage/100)
+maxExpected := expected * (1 + tolerancePercentage/100)
+
+actual := float64(mirroredCounts[mirrorPod.Name])
+tlog.Logf(t, "Pod: %s, Expected: %f (min: %f, max: %f), Actual: %f", mirrorPod.Name, expected, minExpected, maxExpected, actual)
+
+if actual < minExpected || actual > maxExpected {
+errs = append(errs, fmt.Errorf("Pod %s did not meet the mirroring percentage within tolerance. Expected between %f and %f, but got %f", mirrorPod.Name, minExpected, maxExpected, actual))
+}
+}
+if len(errs) > 0 {
+return errors.Join(errs...)
+}
+tlog.Log(t, "Validated mirrored request logs across all desired backends within the given tolerance")
+return nil
+}

conformance/tests/httproute-request-percentage-mirror.yaml

@@ -0,0 +1,71 @@
+apiVersion: gateway.networking.k8s.io/v1
+kind: HTTPRoute
+metadata:
+ name: request-percentage-mirror
+ namespace: gateway-conformance-infra
+spec:
+ parentRefs:
+ - name: same-namespace
+ rules:
+ - matches:
+ - path:
+ type: PathPrefix
+ value: /percent-mirror
+ filters:
+ - type: RequestMirror
+ requestMirror:
+ backendRef:
+ name: infra-backend-v2
+ namespace: gateway-conformance-infra
+ port: 8080
+ percent: 20
+ backendRefs:
+ - name: infra-backend-v1
+ port: 8080
+ namespace: gateway-conformance-infra
+ - matches:
+ - path:
+ type: PathPrefix
+ value: /percent-mirror-fraction
+ filters:
+ - type: RequestMirror
+ requestMirror:
+ backendRef:
+ name: infra-backend-v2
+ namespace: gateway-conformance-infra
+ port: 8080
+ fraction:
+ numerator: 25
+ denominator: 50
+ backendRefs:
+ - name: infra-backend-v1
+ port: 8080
+ namespace: gateway-conformance-infra
+ - matches:
+ - path:
+ type: PathPrefix
+ value: /percent-mirror-and-modify-headers
+ filters:
+ - type: RequestHeaderModifier
+ requestHeaderModifier:
+ set:
+ - name: X-Header-Set
+ value: set-overwrites-values
+ add:
+ - name: X-Header-Add
+ value: header-val-1
+ - name: X-Header-Add-Append
+ value: header-val-2
+ remove:
+ - X-Header-Remove
+ - type: RequestMirror
+ requestMirror:
+ backendRef:
+ name: infra-backend-v2
+ namespace: gateway-conformance-infra
+ port: 8080
+ percent: 35
+ backendRefs:
+ - name: infra-backend-v1
+ port: 8080
+ namespace: gateway-conformance-infra