feat(gateway-api): Add custom backendRef and filters support for HTTP…

…Route

Signed-off-by: kahirokunn <okinakahiro@gmail.com>

pkg/apis/flagger/v1beta1/canary.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"time"
 
+	v1 "github.com/fluxcd/flagger/pkg/apis/gatewayapi/v1"
 	"github.com/fluxcd/flagger/pkg/apis/gatewayapi/v1beta1"
 	istiov1beta1 "github.com/fluxcd/flagger/pkg/apis/istio/v1beta1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -213,11 +214,11 @@ type CanaryService struct {
 
 	// Primary is the metadata to add to the primary service
 	// +optional
-	Primary *CustomMetadata `json:"primary,omitempty"`
+	Primary *CustomBackend `json:"primary,omitempty"`
 
 	// Canary is the metadata to add to the canary service
 	// +optional
-	Canary *CustomMetadata `json:"canary,omitempty"`
+	Canary *CustomBackend `json:"canary,omitempty"`
 }
 
 // CanaryAnalysis is used to describe how the analysis should be done
@@ -496,6 +497,38 @@ type CustomMetadata struct {
 	Annotations map[string]string `json:"annotations,omitempty"`
 }
 
+// CustomBackend holds labels, annotations, and proxyRef to set on generated objects.
+type CustomBackend struct {
+	CustomMetadata
+
+	// Backend is a reference to a backend to forward matched requests to.
+	// Defaults to the primary or canary service.
+	// +optional
+	Backend *HTTPBackendRefTemplate `json:"backendRef,omitempty"`
+}
+
+// HTTPBackendRefTemplate is a reference to a backend to forward matched requests to.
+type HTTPBackendRefTemplate struct {
+	// Ref references a Kubernetes object.
+	BackendObjectReference *v1.BackendObjectReference `json:"ref,omitempty"`
+
+	// Filters defined at this level should be executed if and only if the
+	// request is being forwarded to the backend defined here.
+	//
+	// Support: Implementation-specific (For broader support of filters, use the
+	// Filters field in HTTPRouteRule.)
+	//
+	// +optional
+	// +kubebuilder:validation:MaxItems=16
+	// +kubebuilder:validation:XValidation:message="May specify either httpRouteFilterRequestRedirect or httpRouteFilterRequestRewrite, but not both",rule="!(self.exists(f, f.type == 'RequestRedirect') && self.exists(f, f.type == 'URLRewrite'))"
+	// +kubebuilder:validation:XValidation:message="May specify either httpRouteFilterRequestRedirect or httpRouteFilterRequestRewrite, but not both",rule="!(self.exists(f, f.type == 'RequestRedirect') && self.exists(f, f.type == 'URLRewrite'))"
+	// +kubebuilder:validation:XValidation:message="RequestHeaderModifier filter cannot be repeated",rule="self.filter(f, f.type == 'RequestHeaderModifier').size() <= 1"
+	// +kubebuilder:validation:XValidation:message="ResponseHeaderModifier filter cannot be repeated",rule="self.filter(f, f.type == 'ResponseHeaderModifier').size() <= 1"
+	// +kubebuilder:validation:XValidation:message="RequestRedirect filter cannot be repeated",rule="self.filter(f, f.type == 'RequestRedirect').size() <= 1"
+	// +kubebuilder:validation:XValidation:message="URLRewrite filter cannot be repeated",rule="self.filter(f, f.type == 'URLRewrite').size() <= 1"
+	Filters []v1.HTTPRouteFilter `json:"filters,omitempty"`
+}
+
 // HTTPRewrite holds information about how to modify a request URI during
 // forwarding.
 type HTTPRewrite struct {

pkg/router/gateway_api.go

@@ -96,12 +96,8 @@ func (gwr *GatewayAPIRouter) Reconcile(canary *flaggerv1.Canary) error {
 				Matches: matches,
 				Filters: gwr.makeFilters(canary),
 				BackendRefs: []v1.HTTPBackendRef{
-					{
-						BackendRef: gwr.makeBackendRef(primarySvcName, initialPrimaryWeight, canary.Spec.Service.Port),
-					},
-					{
-						BackendRef: gwr.makeBackendRef(canarySvcName, initialCanaryWeight, canary.Spec.Service.Port),
-					},
+					gwr.makeHTTPBackendRef(primarySvcName, initialPrimaryWeight, canary.Spec.Service.Port, canary.Spec.Service.Primary),
+					gwr.makeHTTPBackendRef(canarySvcName, initialCanaryWeight, canary.Spec.Service.Port, canary.Spec.Service.Canary),
 				},
 			},
 		},
@@ -122,9 +118,7 @@ func (gwr *GatewayAPIRouter) Reconcile(canary *flaggerv1.Canary) error {
 			Matches: matches,
 			Filters: gwr.makeFilters(canary),
 			BackendRefs: []v1.HTTPBackendRef{
-				{
-					BackendRef: gwr.makeBackendRef(primarySvcName, initialPrimaryWeight, canary.Spec.Service.Port),
-				},
+				gwr.makeHTTPBackendRef(primarySvcName, initialPrimaryWeight, canary.Spec.Service.Port, canary.Spec.Service.Primary),
 			},
 		})
 		if canary.Spec.Service.Timeout != "" {
@@ -340,12 +334,8 @@ func (gwr *GatewayAPIRouter) SetRoutes(
 		Matches: matches,
 		Filters: gwr.makeFilters(canary),
 		BackendRefs: []v1.HTTPBackendRef{
-			{
-				BackendRef: gwr.makeBackendRef(primarySvcName, pWeight, canary.Spec.Service.Port),
-			},
-			{
-				BackendRef: gwr.makeBackendRef(canarySvcName, cWeight, canary.Spec.Service.Port),
-			},
+			gwr.makeHTTPBackendRef(primarySvcName, pWeight, canary.Spec.Service.Port, canary.Spec.Service.Primary),
+			gwr.makeHTTPBackendRef(canarySvcName, cWeight, canary.Spec.Service.Port, canary.Spec.Service.Canary),
 		},
 	}
 	if canary.Spec.Service.Timeout != "" {
@@ -399,9 +389,7 @@ func (gwr *GatewayAPIRouter) SetRoutes(
 			Matches: matches,
 			Filters: gwr.makeFilters(canary),
 			BackendRefs: []v1.HTTPBackendRef{
-				{
-					BackendRef: gwr.makeBackendRef(primarySvcName, initialPrimaryWeight, canary.Spec.Service.Port),
-				},
+				gwr.makeHTTPBackendRef(primarySvcName, initialPrimaryWeight, canary.Spec.Service.Port, canary.Spec.Service.Primary),
 			},
 			Timeouts: &v1.HTTPRouteTimeouts{
 				Request: &timeout,
@@ -484,12 +472,8 @@ func (gwr *GatewayAPIRouter) getSessionAffinityRouteRules(canary *flaggerv1.Cana
 		mergedMatches := gwr.mergeMatchConditions([]v1.HTTPRouteMatch{cookieMatch}, svcMatches)
 		stickyRouteRule.Matches = mergedMatches
 		stickyRouteRule.BackendRefs = []v1.HTTPBackendRef{
-			{
-				BackendRef: gwr.makeBackendRef(primarySvcName, 0, canary.Spec.Service.Port),
-			},
-			{
-				BackendRef: gwr.makeBackendRef(canarySvcName, 100, canary.Spec.Service.Port),
-			},
+			gwr.makeHTTPBackendRef(primarySvcName, 0, canary.Spec.Service.Port, canary.Spec.Service.Primary),
+			gwr.makeHTTPBackendRef(canarySvcName, 100, canary.Spec.Service.Port, canary.Spec.Service.Canary),
 		}
 	} else {
 		// If canary weight is 0 and SessionAffinityCookie is non-blank, then it belongs to a previous canary run.
@@ -612,16 +596,28 @@ func (gwr *GatewayAPIRouter) mapRouteMatches(requestMatches []istiov1beta1.HTTPM
 	return matches, nil
 }
 
-func (gwr *GatewayAPIRouter) makeBackendRef(svcName string, weight, port int32) v1.BackendRef {
-	return v1.BackendRef{
-		BackendObjectReference: v1.BackendObjectReference{
-			Group: (*v1.Group)(&backendRefGroup),
-			Kind:  (*v1.Kind)(&backendRefKind),
-			Name:  v1.ObjectName(svcName),
-			Port:  (*v1.PortNumber)(&port),
+func (gwr *GatewayAPIRouter) makeHTTPBackendRef(svcName string, weight, port int32, customBackend *flaggerv1.CustomBackend) v1.HTTPBackendRef {
+	httpBackendRef := v1.HTTPBackendRef{
+		BackendRef: v1.BackendRef{
+			BackendObjectReference: v1.BackendObjectReference{
+				Group: (*v1.Group)(&backendRefGroup),
+				Kind:  (*v1.Kind)(&backendRefKind),
+				Name:  v1.ObjectName(svcName),
+				Port:  (*v1.PortNumber)(&port),
+			},
+			Weight: &weight,
 		},
-		Weight: &weight,
 	}
+	if customBackend != nil && customBackend.Backend != nil {
+		if customBackend.Backend.BackendObjectReference != nil {
+			httpBackendRef.BackendObjectReference = *customBackend.Backend.BackendObjectReference
+		}
+		if customBackend.Backend.Filters != nil {
+			httpBackendRef.Filters = customBackend.Backend.Filters
+		}
+	}
+
+	return httpBackendRef
 }
 
 func (gwr *GatewayAPIRouter) mergeMatchConditions(analysis, service []v1.HTTPRouteMatch) []v1.HTTPRouteMatch {

pkg/router/gateway_api_test.go

@@ -295,12 +295,8 @@ func TestGatewayAPIRouter_getSessionAffinityRouteRules(t *testing.T) {
 	_, pSvcName, cSvcName := canary.GetServiceNames()
 	weightedRouteRule := &v1.HTTPRouteRule{
 		BackendRefs: []v1.HTTPBackendRef{
-			{
-				BackendRef: router.makeBackendRef(pSvcName, initialPrimaryWeight, canary.Spec.Service.Port),
-			},
-			{
-				BackendRef: router.makeBackendRef(cSvcName, initialCanaryWeight, canary.Spec.Service.Port),
-			},
+			router.makeHTTPBackendRef(pSvcName, initialPrimaryWeight, canary.Spec.Service.Port, canary.Spec.Service.Primary),
+			router.makeHTTPBackendRef(cSvcName, initialCanaryWeight, canary.Spec.Service.Port, canary.Spec.Service.Canary),
 		},
 	}
 	rules, err := router.getSessionAffinityRouteRules(canary, 10, weightedRouteRule)

pkg/router/kubernetes_default.go

@@ -50,13 +50,21 @@ func (c *KubernetesDefaultRouter) Initialize(canary *flaggerv1.Canary) error {
 	_, primaryName, canaryName := canary.GetServiceNames()
 
 	// canary svc
-	err := c.reconcileService(canary, canaryName, c.labelValue, canary.Spec.Service.Canary)
+	canaryCustomMetadata := &flaggerv1.CustomMetadata{}
+	if canary.Spec.Service.Canary != nil {
+		canaryCustomMetadata = &canary.Spec.Service.Canary.CustomMetadata
+	}
+	err := c.reconcileService(canary, canaryName, c.labelValue, canaryCustomMetadata)
 	if err != nil {
 		return fmt.Errorf("reconcileService failed: %w", err)
 	}
 
 	// primary svc
-	err = c.reconcileService(canary, primaryName, fmt.Sprintf("%s-primary", c.labelValue), canary.Spec.Service.Primary)
+	primaryCustomMetadata := &flaggerv1.CustomMetadata{}
+	if canary.Spec.Service.Primary != nil {
+		primaryCustomMetadata = &canary.Spec.Service.Primary.CustomMetadata
+	}
+	err = c.reconcileService(canary, primaryName, fmt.Sprintf("%s-primary", c.labelValue), primaryCustomMetadata)
 	if err != nil {
 		return fmt.Errorf("reconcileService failed: %w", err)
 	}

pkg/router/kubernetes_default_test.go

@@ -375,13 +375,13 @@ func TestServiceRouter_InitializeMetadata(t *testing.T) {
 		labelSelector: "app",
 	}
 
-	metadata := &flaggerv1.CustomMetadata{
-		Labels:      map[string]string{"test": "test"},
-		Annotations: map[string]string{"test": "test"},
+	mocks.canary.Spec.Service.Canary = &flaggerv1.CustomBackend{
+		CustomMetadata: flaggerv1.CustomMetadata{
+			Labels:      map[string]string{"test": "test"},
+			Annotations: map[string]string{"test": "test"},
+		},
 	}
 
-	mocks.canary.Spec.Service.Canary = metadata
-
 	err := router.Initialize(mocks.canary)
 	require.NoError(t, err)