Allow policy target namespace to be optional (#1926)

* Defaults to the policy namespace as
recommend by upstream
https://github.com/kubernetes-sigs/gateway-api/blob/d38e6c81ba3d3f137012ceeec8262ab40ad0cd81/apis/v1alpha2/policy_types.go#L47

Signed-off-by: Arko Dasgupta <arko@tetrate.io>

internal/gatewayapi/clienttrafficpolicy.go

@@ -17,6 +17,7 @@ import (
 
 	egv1a1 "github.com/envoyproxy/gateway/api/v1alpha1"
 	"github.com/envoyproxy/gateway/internal/status"
+	"github.com/envoyproxy/gateway/internal/utils/ptr"
 )
 
 const (
@@ -170,16 +171,9 @@ func ProcessClientTrafficPolicies(clientTrafficPolicies []*egv1a1.ClientTrafficP
 
 func getGatewayTargetRef(policy *egv1a1.ClientTrafficPolicy, gateways []*GatewayContext) *GatewayContext {
 	targetNs := policy.Spec.TargetRef.Namespace
-
-	// Ensure Namespace is set
+	// If empty, default to namespace of policy
 	if targetNs == nil {
-		status.SetClientTrafficPolicyCondition(policy,
-			gwv1a2.PolicyConditionAccepted,
-			metav1.ConditionFalse,
-			gwv1a2.PolicyReasonInvalid,
-			"TargetRef.Namespace must be set",
-		)
-		return nil
+		targetNs = ptr.To(gwv1b1.Namespace(policy.Namespace))
 	}
 
 	// Ensure policy can only target a Gateway

internal/gatewayapi/envoypatchpolicy.go

@@ -16,6 +16,7 @@ import (
 	egv1a1 "github.com/envoyproxy/gateway/api/v1alpha1"
 	"github.com/envoyproxy/gateway/internal/ir"
 	"github.com/envoyproxy/gateway/internal/status"
+	"github.com/envoyproxy/gateway/internal/utils/ptr"
 )
 
 func (t *Translator) ProcessEnvoyPatchPolicies(envoyPatchPolicies []*egv1a1.EnvoyPatchPolicy, xdsIR XdsIRMap) {
@@ -27,18 +28,10 @@ func (t *Translator) ProcessEnvoyPatchPolicies(envoyPatchPolicies []*egv1a1.Envo
 	for _, policy := range envoyPatchPolicies {
 		policy := policy.DeepCopy()
 		targetNs := policy.Spec.TargetRef.Namespace
-		if targetNs == nil {
-			// This status condition will not get updated in the resource because
-			// we dont have access to the IR yet, but it has been kept here in case we publish
-			// the status from this layer instead of the xds layer.
 
-			status.SetEnvoyPatchPolicyCondition(policy,
-				gwv1a2.PolicyConditionAccepted,
-				metav1.ConditionFalse,
-				gwv1a2.PolicyReasonInvalid,
-				"TargetRef.Namespace must be set",
-			)
-			continue
+		// If empty, default to namespace of policy
+		if targetNs == nil {
+			targetNs = ptr.To(gwv1b1.Namespace(policy.Namespace))
 		}
 
 		// Get the IR