fix: avoid duplicate BackendRefs (#104)

* fix: avoid duplicate `BackendRefs`

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: check for nil

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: change to %d

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: use interface and assign nil

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: move check after toBackendRef

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: move to function

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: merge conflict

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: apply suggestions from review

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: add test case for duplicated backends

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: apply suggestions

Signed-off-by: Navendu Pottekkat <[email protected]>

* fix: enforce group and kind

Signed-off-by: Navendu Pottekkat <[email protected]>

* revert last commit

---------

Signed-off-by: Navendu Pottekkat <[email protected]>
Co-authored-by: Lior Lieberman <[email protected]>

Author: pottekkat

pkg/i2gw/providers/common/converter.go

@@ -328,7 +328,7 @@ func (rg *ingressRuleGroup) configureBackendRef(paths []ingressPath) ([]gatewayv
 		backendRefs = append(backendRefs, gatewayv1.HTTPBackendRef{BackendRef: *backendRef})
 	}
 
-	return backendRefs, errors
+	return removeBackendRefsDuplicates(backendRefs), errors
 }
 
 func getPathMatchKey(ip ingressPath) pathMatchKey {

pkg/i2gw/providers/common/converter_test.go

@@ -311,6 +311,104 @@ func Test_ingresses2GatewaysAndHttpRoutes(t *testing.T) {
 			},
 			expectedErrors: field.ErrorList{},
 		},
+		{
+			name: "duplicated backends",
+			ingresses: []networkingv1.Ingress{{
+				ObjectMeta: metav1.ObjectMeta{Name: "duplicate-a", Namespace: "test"},
+				Spec: networkingv1.IngressSpec{
+					IngressClassName: PtrTo("example-proxy"),
+					Rules: []networkingv1.IngressRule{{
+						Host: "example.com",
+						IngressRuleValue: networkingv1.IngressRuleValue{
+							HTTP: &networkingv1.HTTPIngressRuleValue{
+								Paths: []networkingv1.HTTPIngressPath{{
+									Path:     "/foo",
+									PathType: &iPrefix,
+									Backend: networkingv1.IngressBackend{
+										Service: &networkingv1.IngressServiceBackend{
+											Name: "example",
+											Port: networkingv1.ServiceBackendPort{
+												Number: 3000,
+											},
+										},
+									},
+								}},
+							},
+						},
+					}},
+				},
+			}, {
+				ObjectMeta: metav1.ObjectMeta{Name: "duplicate-b", Namespace: "test"},
+				Spec: networkingv1.IngressSpec{
+					IngressClassName: PtrTo("example-proxy"),
+					Rules: []networkingv1.IngressRule{{
+						Host: "example.com",
+						IngressRuleValue: networkingv1.IngressRuleValue{
+							HTTP: &networkingv1.HTTPIngressRuleValue{
+								Paths: []networkingv1.HTTPIngressPath{{
+									Path:     "/foo",
+									PathType: &iPrefix,
+									Backend: networkingv1.IngressBackend{
+										Service: &networkingv1.IngressServiceBackend{
+											Name: "example",
+											Port: networkingv1.ServiceBackendPort{
+												Number: 3000,
+											},
+										},
+									},
+								}},
+							},
+						},
+					}},
+				},
+			}},
+			expectedGatewayResources: i2gw.GatewayResources{
+				Gateways: map[types.NamespacedName]gatewayv1.Gateway{
+					{Namespace: "test", Name: "example-proxy"}: {
+						ObjectMeta: metav1.ObjectMeta{Name: "example-proxy", Namespace: "test"},
+						Spec: gatewayv1.GatewaySpec{
+							GatewayClassName: "example-proxy",
+							Listeners: []gatewayv1.Listener{{
+								Name:     "example-com-http",
+								Port:     80,
+								Protocol: gatewayv1.HTTPProtocolType,
+								Hostname: PtrTo(gatewayv1.Hostname("example.com")),
+							}},
+						},
+					},
+				},
+				HTTPRoutes: map[types.NamespacedName]gatewayv1.HTTPRoute{
+					{Namespace: "test", Name: "duplicate-a-example-com"}: {
+						ObjectMeta: metav1.ObjectMeta{Name: "duplicate-a-example-com", Namespace: "test"},
+						Spec: gatewayv1.HTTPRouteSpec{
+							CommonRouteSpec: gatewayv1.CommonRouteSpec{
+								ParentRefs: []gatewayv1.ParentReference{{
+									Name: "example-proxy",
+								}},
+							},
+							Hostnames: []gatewayv1.Hostname{"example.com"},
+							Rules: []gatewayv1.HTTPRouteRule{{
+								Matches: []gatewayv1.HTTPRouteMatch{{
+									Path: &gatewayv1.HTTPPathMatch{
+										Type:  &gPathPrefix,
+										Value: PtrTo("/foo"),
+									},
+								}},
+								BackendRefs: []gatewayv1.HTTPBackendRef{{
+									BackendRef: gatewayv1.BackendRef{
+										BackendObjectReference: gatewayv1.BackendObjectReference{
+											Name: "example",
+											Port: PtrTo(gatewayv1.PortNumber(3000)),
+										},
+									},
+								}},
+							}},
+						},
+					},
+				},
+			},
+			expectedErrors: field.ErrorList{},
+		},
 	}
 
 	for _, tc := range testCases {

pkg/i2gw/providers/common/utils.go

@@ -155,3 +155,48 @@ func groupIngressPathsByMatchKey(rules []ingressRule) orderedIngressPathsByMatch
 func PtrTo[T any](a T) *T {
 	return &a
 }
+
+type uniqueBackendRefsKey struct {
+	Name      gatewayv1.ObjectName
+	Namespace gatewayv1.Namespace
+	Port      gatewayv1.PortNumber
+	Group     gatewayv1.Group
+	Kind      gatewayv1.Kind
+}
+
+// removeBackendRefsDuplicates removes duplicate backendRefs from a list of backendRefs.
+func removeBackendRefsDuplicates(backendRefs []gatewayv1.HTTPBackendRef) []gatewayv1.HTTPBackendRef {
+	var uniqueBackendRefs []gatewayv1.HTTPBackendRef
+	uniqueKeys := map[uniqueBackendRefsKey]struct{}{}
+
+	for _, backendRef := range backendRefs {
+		var k uniqueBackendRefsKey
+
+		group := gatewayv1.Group("")
+		kind := gatewayv1.Kind("Service")
+
+		if backendRef.Group != nil && *backendRef.Group != "core" {
+			group = *backendRef.Group
+		}
+
+		if backendRef.Kind != nil {
+			kind = *backendRef.Kind
+		}
+
+		k.Name = backendRef.Name
+		k.Group = group
+		k.Kind = kind
+
+		if backendRef.Port != nil {
+			k.Port = *backendRef.Port
+		}
+
+		if _, exists := uniqueKeys[k]; exists {
+			continue
+		}
+
+		uniqueKeys[k] = struct{}{}
+		uniqueBackendRefs = append(uniqueBackendRefs, backendRef)
+	}
+	return uniqueBackendRefs
+}