Add support for Google GCE provider

README.md

@@ -115,6 +115,7 @@ Ingress2gateway also supports translating provider-specific resources and ingres
 - [kong](pkg/i2gw/providers/kong/README.md)
 - [istio](pkg/i2gw/providers/istio/README.md)
 - [apisix](pkg/i2gw/providers/apisix/README.md)
+- [gce](pkg/i2gw/providers/gce/README.md)
 
 If your provider, or a specific feature, is not currently supported, please open an issue and describe your use case.
 

cmd/print.go

@@ -29,6 +29,7 @@ import (
 
 	// Call init function for the providers
 	_ "github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw/providers/apisix"
+	_ "github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw/providers/gce"
 	_ "github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw/providers/ingressnginx"
 	_ "github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw/providers/istio"
 	_ "github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw/providers/kong"

pkg/i2gw/providers/apisix/resource_reader.go

@@ -21,6 +21,7 @@ import (
 
 	"github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw"
 	"github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw/providers/common"
+	"k8s.io/apimachinery/pkg/util/sets"
 )
 
 // converter implements the i2gw.CustomResourceReader interface.
@@ -39,7 +40,7 @@ func (r *resourceReader) readResourcesFromCluster(ctx context.Context) (*storage
 	// read apisix related resources from cluster.
 	storage := newResourcesStorage()
 
-	ingresses, err := common.ReadIngressesFromCluster(ctx, r.conf.Client, ApisixIngressClass)
+	ingresses, err := common.ReadIngressesFromCluster(ctx, r.conf.Client, sets.New(ApisixIngressClass))
 	if err != nil {
 		return nil, err
 	}
@@ -51,7 +52,7 @@ func (r *resourceReader) readResourcesFromFile(filename string) (*storage, error
 	// read apisix related resources from file.
 	storage := newResourcesStorage()
 
-	ingresses, err := common.ReadIngressesFromFile(filename, r.conf.Namespace, ApisixIngressClass)
+	ingresses, err := common.ReadIngressesFromFile(filename, r.conf.Namespace, sets.New[string](ApisixIngressClass))
 	if err != nil {
 		return nil, err
 	}

pkg/i2gw/providers/common/converter.go

@@ -22,7 +22,6 @@ import (
 
 	"github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw"
 	networkingv1 "k8s.io/api/networking/v1"
-	networkingv1beta1 "k8s.io/api/networking/v1beta1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/types"
@@ -135,14 +134,7 @@ type ingressPath struct {
 }
 
 func (a *ingressAggregator) addIngress(ingress networkingv1.Ingress) {
-	var ingressClass string
-	if ingress.Spec.IngressClassName != nil && *ingress.Spec.IngressClassName != "" {
-		ingressClass = *ingress.Spec.IngressClassName
-	} else if _, ok := ingress.Annotations[networkingv1beta1.AnnotationIngressClass]; ok {
-		ingressClass = ingress.Annotations[networkingv1beta1.AnnotationIngressClass]
-	} else {
-		ingressClass = ingress.Name
-	}
+	ingressClass := GetIngressClass(ingress)
 	for _, rule := range ingress.Spec.Rules {
 		a.addIngressRule(ingress.Namespace, ingress.Name, ingressClass, rule, ingress.Spec)
 	}

pkg/i2gw/providers/common/converter_test.go

@@ -73,6 +73,7 @@ func Test_ingresses2GatewaysAndHttpRoutes(t *testing.T) {
 							},
 						},
 					}},
+					IngressClassName: PtrTo("simple"),
 				},
 			}},
 			expectedGatewayResources: i2gw.GatewayResources{
@@ -150,6 +151,7 @@ func Test_ingresses2GatewaysAndHttpRoutes(t *testing.T) {
 							},
 						},
 					}},
+					IngressClassName: PtrTo("with-tls"),
 				},
 			}},
 			expectedGatewayResources: i2gw.GatewayResources{

pkg/i2gw/providers/common/resource_reader.go

@@ -28,11 +28,12 @@ import (
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/util/sets"
 	kubeyaml "k8s.io/apimachinery/pkg/util/yaml"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 )
 
-func ReadIngressesFromCluster(ctx context.Context, client client.Client, ingressClass string) (map[types.NamespacedName]*networkingv1.Ingress, error) {
+func ReadIngressesFromCluster(ctx context.Context, client client.Client, ingressClasses sets.Set[string]) (map[types.NamespacedName]*networkingv1.Ingress, error) {
 	var ingressList networkingv1.IngressList
 	err := client.List(ctx, &ingressList)
 	if err != nil {
@@ -41,7 +42,7 @@ func ReadIngressesFromCluster(ctx context.Context, client client.Client, ingress
 
 	ingresses := map[types.NamespacedName]*networkingv1.Ingress{}
 	for i, ingress := range ingressList.Items {
-		if GetIngressClass(ingress) != ingressClass {
+		if !ingressClasses.Has(GetIngressClass(ingress)) {
 			continue
 		}
 		ingresses[types.NamespacedName{Namespace: ingress.Namespace, Name: ingress.Name}] = &ingressList.Items[i]
@@ -50,7 +51,7 @@ func ReadIngressesFromCluster(ctx context.Context, client client.Client, ingress
 	return ingresses, nil
 }
 
-func ReadIngressesFromFile(filename, namespace, ingressClass string) (map[types.NamespacedName]*networkingv1.Ingress, error) {
+func ReadIngressesFromFile(filename, namespace string, ingressClasses sets.Set[string]) (map[types.NamespacedName]*networkingv1.Ingress, error) {
 	stream, err := os.ReadFile(filename)
 	if err != nil {
 		return nil, fmt.Errorf("failed to read file %v: %w", filename, err)
@@ -70,7 +71,7 @@ func ReadIngressesFromFile(filename, namespace, ingressClass string) (map[types.
 			if err != nil {
 				return nil, err
 			}
-			if GetIngressClass(ingress) != ingressClass {
+			if !ingressClasses.Has(GetIngressClass(ingress)) {
 				continue
 			}
 			ingresses[types.NamespacedName{Namespace: ingress.Namespace, Name: ingress.Name}] = &ingress

pkg/i2gw/providers/common/utils.go

@@ -34,7 +34,7 @@ func GetIngressClass(ingress networkingv1.Ingress) string {
 	} else if _, ok := ingress.Annotations[networkingv1beta1.AnnotationIngressClass]; ok {
 		ingressClass = ingress.Annotations[networkingv1beta1.AnnotationIngressClass]
 	} else {
-		ingressClass = ingress.Name
+		ingressClass = ""
 	}
 
 	return ingressClass

pkg/i2gw/providers/gce/README.md

@@ -0,0 +1,46 @@
+# GCE Provider
+
+The project supports translating ingress-gce specific annotations.
+
+Currently supported annotations:
+`kubernetes.io/ingress.class`: Though it is a deprecated annotation for most providers, GCE still uses this annotation to specify the specific type of load balancers created by GKE Ingress.
+
+## Implementation-specific features
+
+The following implementation-specific features are supported:
+
+- Ingress path with type `ImplementationSpecific` will:
+  - Translate to equivalent Gateway Prefix path but dropping `/*`, if `/*` exists
+  - Translate to equivalent Exact path otherwise.
+
+Examples:
+| Ingress `ImplementationSpecific` Path | map to Gateway Path                    |
+| ------------------------------------- | -------------------------------------- |
+| /*                                    | / Prefix                               |
+| /v1                                   | /v1 Exact                              |
+| /v1/                                  | /v1/ Exact                             |
+| /v1/*                                 | /v1 Prefix                             |
+
+Note: For Ingress `ImplementationSpecific` path with `/v1/*`, it will map to
+`/v1/` or `/v1/v2` but not `/v1`. If you want to avoid such behavior,
+please consider switching to `Prefix`, `Exact`, or an `ImplementationSpecific`
+path without `*` before converting Ingress to Gateway.
+
+## Feature list
+Currently supported:
+- [Basic Internal Ingress](https://github.com/GoogleCloudPlatform/gke-networking-recipes/tree/main/ingress/single-cluster/ingress-internal-basic)
+- [Basic external Ingress](https://github.com/GoogleCloudPlatform/gke-networking-recipes/tree/main/ingress/single-cluster/ingress-external-basic)
+- [Ingress with custom default backend](https://github.com/GoogleCloudPlatform/gke-networking-recipes/tree/main/ingress/single-cluster/ingress-custom-default-backend)
+
+To be supported:
+ - [Ingress with custom HTTP health check](https://github.com/GoogleCloudPlatform/gke-networking-recipes/tree/main/ingress/single-cluster/ingress-custom-http-health-check)
+ - [IAP enabled ingress](https://github.com/GoogleCloudPlatform/gke-networking-recipes/tree/main/ingress/single-cluster/ingress-iap)
+ - [Google Cloud Armor enabled ingress](https://github.com/GoogleCloudPlatform/gke-networking-recipes/blob/main/ingress/single-cluster/ingress-cloudarmor/README.md)
+ - [Ingress with HTTPS redirect](https://github.com/GoogleCloudPlatform/gke-networking-recipes/tree/main/ingress/single-cluster/ingress-https)
+
+## Summary of GKE Ingress annotation
+External Ingress:
+https://cloud.google.com/kubernetes-engine/docs/how-to/load-balance-ingress#summary_of_external_ingress_annotations
+
+Internal Ingress:
+https://cloud.google.com/kubernetes-engine/docs/how-to/internal-load-balance-ingress#summary_of_internal_ingress_annotations

pkg/i2gw/providers/gce/converter.go

@@ -0,0 +1,71 @@
+/*
+Copyright 2024 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 gce
+
+import (
+	"github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw"
+	"github.com/kubernetes-sigs/ingress2gateway/pkg/i2gw/providers/common"
+	networkingv1 "k8s.io/api/networking/v1"
+	"k8s.io/apimachinery/pkg/util/validation/field"
+)
+
+// converter implements the ToGatewayAPI function of i2gw.ResourceConverter interface.
+type converter struct {
+	conf *i2gw.ProviderConf
+
+	featureParsers                []i2gw.FeatureParser
+	implementationSpecificOptions i2gw.ProviderImplementationSpecificOptions
+}
+
+// newConverter returns an ingress-gce converter instance.
+func newConverter(conf *i2gw.ProviderConf) converter {
+	return converter{
+		conf:           conf,
+		featureParsers: []i2gw.FeatureParser{},
+		implementationSpecificOptions: i2gw.ProviderImplementationSpecificOptions{
+			ToImplementationSpecificHTTPPathTypeMatch: implementationSpecificHTTPPathTypeMatch,
+		},
+	}
+}
+
+func (c *converter) convert(storage *storage) (i2gw.GatewayResources, field.ErrorList) {
+	ingressList := []networkingv1.Ingress{}
+	for _, ing := range storage.Ingresses {
+		ingressList = append(ingressList, *ing)
+	}
+
+	// Convert plain ingress resources to gateway resources, ignoring all
+	// provider-specific features.
+	gatewayResources, errs := common.ToGateway(ingressList, c.implementationSpecificOptions)
+	if len(errs) > 0 {
+		return i2gw.GatewayResources{}, errs
+	}
+
+	errs = setGCEGatewayClasses(ingressList, &gatewayResources)
+	if len(errs) > 0 {
+		return i2gw.GatewayResources{}, errs
+	}
+
+	for _, parseFeatureFunc := range c.featureParsers {
+		// Apply the feature parsing function to the gateway resources, one by one.
+		parseErrs := parseFeatureFunc(ingressList, &gatewayResources)
+		// Append the parsing errors to the error list.
+		errs = append(errs, parseErrs...)
+	}
+
+	return gatewayResources, errs
+}