[feat gw-api]add dedupe in route mapper

Author: shuqz

pkg/gateway/routeutils/route_listener_mapper.go

@@ -48,6 +48,8 @@ func (ltr *listenerToRouteMapperImpl) mapGatewayAndRoutes(ctx context.Context, g
 		}
 	}
 
+	// Dedupe - Check if route already exists for this port before adding
+	seenRoutesPerPort := make(map[int]map[types.NamespacedName]bool)
 	// Next, greedily looking for the route to attach to.
 	for _, listener := range gw.Spec.Listeners {
 		// used for cross serving check
@@ -74,14 +76,20 @@ func (ltr *listenerToRouteMapperImpl) mapGatewayAndRoutes(ctx context.Context, g
 
 			if allowedAttachment {
 				port := int32(listener.Port)
-				result[int(port)] = append(result[int(port)], route)
+				routeKey := route.GetRouteNamespacedName()
+				if seenRoutesPerPort[int(port)] == nil {
+					seenRoutesPerPort[int(port)] = make(map[types.NamespacedName]bool)
+				}
+				if !seenRoutesPerPort[int(port)][routeKey] {
+					seenRoutesPerPort[int(port)][routeKey] = true
+					result[int(port)] = append(result[int(port)], route)
+				}
 
 				// Store compatible hostnames per port per route
 				if compatibleHostnamesByPort[port] == nil {
 					compatibleHostnamesByPort[port] = make(map[types.NamespacedName][]gwv1.Hostname)
 				}
 				// Append hostnames for routes that attach to multiple listeners on the same port
-				routeKey := route.GetRouteNamespacedName()
 				compatibleHostnamesByPort[port][routeKey] = append(compatibleHostnamesByPort[port][routeKey], compatibleHostnames...)
 			}
 		}

pkg/gateway/routeutils/route_listener_mapper_test.go

@@ -3,12 +3,13 @@ package routeutils
 import (
 	"context"
 	"fmt"
+	"testing"
+
 	"github.com/go-logr/logr"
 	"github.com/stretchr/testify/assert"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	gwv1 "sigs.k8s.io/gateway-api/apis/v1"
-	"testing"
 )
 
 type mockListenerAttachmentHelper struct {
@@ -299,6 +300,42 @@ func Test_mapGatewayAndRoutes(t *testing.T) {
 			name:     "no output",
 			expected: make(map[int][]preLoadRouteDescriptor),
 		},
+		{
+			name: "route attaches to multiple listeners on same port - verify deduplication",
+			gw: gwv1.Gateway{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "gw1",
+					Namespace: "ns-gw",
+				},
+				Spec: gwv1.GatewaySpec{
+					Listeners: []gwv1.Listener{
+						{
+							Name: "listener1-port80",
+							Port: gwv1.PortNumber(80),
+						},
+						{
+							Name: "listener2-port80",
+							Port: gwv1.PortNumber(80),
+						},
+					},
+				},
+			},
+			routes: []preLoadRouteDescriptor{route1},
+			listenerAttachmentMap: map[string]bool{
+				"listener1-port80-80-route1-ns1": true,
+				"listener2-port80-80-route1-ns1": true,
+			},
+			routeListenerMap: map[string]bool{
+				"listener1-port80-80-route1-ns1": true,
+				"listener2-port80-80-route1-ns1": true,
+			},
+			routeGatewayMap: map[string]bool{
+				makeRouteGatewayMapKey(gateway, route1): true,
+			},
+			expected: map[int][]preLoadRouteDescriptor{
+				80: {route1}, // Only one route1, not duplicated
+			},
+		},
 	}
 
 	for _, tc := range testCases {