Improve validation to catch use of armID as name (#3621)

* Improve validation to catch use of armID as name

* Add test

* Update v2/internal/resolver/resolver_test.go

Co-authored-by: Bevan Arps <bevan.arps@microsoft.com>

* Fix assertions

---------

Co-authored-by: Bevan Arps <bevan.arps@microsoft.com>

v2/internal/resolver/resolver.go

@@ -8,6 +8,7 @@ package resolver
 import (
 	"context"
 
+	"github.com/Azure/azure-sdk-for-go/sdk/azcore/arm"
 	"github.com/pkg/errors"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -168,6 +169,11 @@ func (r *Resolver) ResolveReference(ctx context.Context, ref genruntime.Namespac
 	refObj, err := r.client.GetObject(ctx, refNamespacedName, refGVK)
 	if err != nil {
 		if apierrors.IsNotFound(err) {
+			// Check if the user has mistakenly put the armID in 'name' field
+			_, err1 := arm.ParseResourceID(ref.Name)
+			if err1 == nil {
+				return nil, errors.Errorf("couldn't resolve reference %s. 'name' looks like it might be an ARM ID; did you mean 'armID: %s'?", refNamespacedName.String(), ref.Name)
+			}
 			err := core.NewReferenceNotFoundError(refNamespacedName, err)
 			return nil, errors.WithStack(err)
 		}

v2/internal/resolver/resolver_test.go

@@ -450,6 +450,26 @@ func Test_ResolveReference_ReturnsErrorIfReferenceIsNotAKubernetesReference(t *t
 	g.Expect(err).To(MatchError("reference abcd is not pointing to a Kubernetes resource"))
 }
 
+func Test_ResolveReference_ReturnsErrorIfReferenceContainsArmIdAsName(t *testing.T) {
+	t.Parallel()
+	g := NewGomegaWithT(t)
+	ctx := context.TODO()
+
+	test, err := testSetup()
+	g.Expect(err).ToNot(HaveOccurred())
+
+	armID := "/subscriptions/00000000-0000-0000-000000000000/resources/resourceGroups/myrg"
+
+	ref := genruntime.ResourceReference{Group: resolver.ResourceGroupGroup, Kind: resolver.ResourceGroupKind, Name: armID}
+	_, err = test.resolver.ResolveReference(ctx, ref.AsNamespacedRef(testNamespace))
+
+	g.Expect(err).To(HaveOccurred())
+	g.Expect(err.Error()).To(ContainSubstring("couldn't resolve reference"))
+	g.Expect(err.Error()).To(ContainSubstring(fmt.Sprintf("%s/%s", testNamespace, armID)))
+	g.Expect(err.Error()).To(ContainSubstring("did you mean 'armID:"))
+	g.Expect(err.Error()).To(ContainSubstring(armID))
+}
+
 func Test_ResolveReferenceToARMID_KubernetesResource_ReturnsExpectedID(t *testing.T) {
 	t.Parallel()
 	g := NewGomegaWithT(t)