fix validation so users can use generateName (#3181)

pkg/apis/serving/v1alpha1/metadata_validation.go

@@ -30,11 +30,22 @@ import (
 // resources is correct.
 func ValidateObjectMetadata(meta metav1.Object) *apis.FieldError {
 	name := meta.GetName()
+	generateName := meta.GetGenerateName()
 
-	msgs := validation.IsDNS1035Label(name)
-	if len(msgs) > 0 {
+	if name != "" {
+		msgs := validation.IsDNS1035Label(name)
+
+		if len(msgs) > 0 {
+			return &apis.FieldError{
+				Message: fmt.Sprintf("not a DNS 1035 label: %v", msgs),
+				Paths:   []string{"name"},
+			}
+		}
+	}
+
+	if generateName == "" && name == "" {
 		return &apis.FieldError{
-			Message: fmt.Sprintf("not a DNS 1035 label: %v", msgs),
+			Message: "name or generateName is required",
 			Paths:   []string{"name"},
 		}
 	}

pkg/apis/serving/v1alpha1/metadata_validation_test.go

@@ -19,10 +19,12 @@ package v1alpha1
 import (
 	"fmt"
 	"reflect"
+	"strings"
 	"testing"
 
 	"github.com/knative/pkg/apis"
 	"github.com/knative/serving/pkg/apis/autoscaling"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
 func TestValidateScaleBoundAnnotations(t *testing.T) {
@@ -96,3 +98,53 @@ func TestValidateScaleBoundAnnotations(t *testing.T) {
 		})
 	}
 }
+
+func TestValidateObjectMetadata(t *testing.T) {
+	cases := []struct {
+		name       string
+		objectMeta metav1.Object
+		expectErr  error
+	}{{
+		name: "invalid name - dots",
+		objectMeta: &metav1.ObjectMeta{
+			Name: "do.not.use.dots",
+		},
+		expectErr: &apis.FieldError{
+			Message: "not a DNS 1035 label: [a DNS-1035 label must consist of lower case alphanumeric characters or '-', start with an alphabetic character, and end with an alphanumeric character (e.g. 'my-name',  or 'abc-123', regex used for validation is '[a-z]([-a-z0-9]*[a-z0-9])?')]",
+			Paths:   []string{"name"},
+		},
+	}, {
+		name: "invalid name - too long",
+		objectMeta: &metav1.ObjectMeta{
+			Name: strings.Repeat("a", 64),
+		},
+		expectErr: &apis.FieldError{
+			Message: "not a DNS 1035 label: [must be no more than 63 characters]",
+			Paths:   []string{"name"},
+		},
+	}, {
+		name: "valid generateName",
+		objectMeta: &metav1.ObjectMeta{
+			GenerateName: "some-name",
+		},
+		expectErr: (*apis.FieldError)(nil),
+	}, {
+		name:       "missing name and generateName",
+		objectMeta: &metav1.ObjectMeta{},
+		expectErr: &apis.FieldError{
+			Message: "name or generateName is required",
+			Paths:   []string{"name"},
+		},
+	}}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+
+			err := ValidateObjectMetadata(c.objectMeta)
+
+			if !reflect.DeepEqual(c.expectErr, err) {
+				t.Errorf("Expected: '%#v', Got: '%#v'", c.expectErr, err)
+			}
+		})
+	}
+}