Validates resource names before storing in inventory

Author: seans3

pkg/object/objmetadata.go

@@ -21,6 +21,7 @@ import (
 
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/validation"
 	"k8s.io/cli-runtime/pkg/resource"
 )
 
@@ -45,10 +46,15 @@ func CreateObjMetadata(namespace string, name string, gk schema.GroupKind) (*Obj
 	// Namespace can be empty, but name cannot.
 	name = strings.TrimSpace(name)
 	if name == "" {
-		return nil, fmt.Errorf("empty name for inventory object")
+		return nil, fmt.Errorf("empty name for object")
+	}
+	// Manually validate name, since by the time k8s reports the error
+	// the invalid name has already been encoded into the inventory object.
+	if !validateNameChars(name) {
+		return nil, fmt.Errorf("invalid characters in object name: %s", name)
 	}
 	if gk.Empty() {
-		return nil, fmt.Errorf("empty GroupKind for inventory object")
+		return nil, fmt.Errorf("empty GroupKind for object")
 	}
 
 	return &ObjMetadata{
@@ -58,6 +64,23 @@ func CreateObjMetadata(namespace string, name string, gk schema.GroupKind) (*Obj
 	}, nil
 }
 
+// validateNameChars returns false if the passed name string contains
+// any invalid characters; true otherwise. The allowed characters for
+// a Kubernetes resource name are:
+//
+//   Most resource types require a name that can be used as a DNS label name
+//   as defined in RFC 1123. This means the name must:
+//
+//   * contain no more than 253 characters
+//   * contain only lowercase alphanumeric characters, '-'
+//   * start with an alphanumeric character
+//   * end with an alphanumeric character
+//
+func validateNameChars(name string) bool {
+	errs := validation.IsDNS1123Subdomain(name)
+	return len(errs) == 0
+}
+
 // ParseObjMetadata takes a string, splits it into its five fields,
 // and returns a pointer to an ObjMetadata struct storing the
 // five fields. Example inventory string:

pkg/object/objmetadata_test.go

@@ -56,13 +56,46 @@ func TestCreateObjMetadata(t *testing.T) {
 			expected:  "",
 			isError:   true,
 		},
+		// Error with invalid name characters "_".
+		{
+			namespace: "test-namespace",
+			name:      "test_name", // Invalid "_" character
+			gk: schema.GroupKind{
+				Group: "apps",
+				Kind:  "ReplicaSet",
+			},
+			expected: "",
+			isError:  true,
+		},
+		// Error name not starting with alphanumeric char
+		{
+			namespace: "test-namespace",
+			name:      "-test",
+			gk: schema.GroupKind{
+				Group: "apps",
+				Kind:  "ReplicaSet",
+			},
+			expected: "",
+			isError:  true,
+		},
+		// Error name not ending with alphanumeric char
+		{
+			namespace: "test-namespace",
+			name:      "test-",
+			gk: schema.GroupKind{
+				Group: "apps",
+				Kind:  "ReplicaSet",
+			},
+			expected: "",
+			isError:  true,
+		},
 	}
 
 	for _, test := range tests {
 		inv, err := CreateObjMetadata(test.namespace, test.name, test.gk)
 		if !test.isError {
 			if err != nil {
-				t.Errorf("Error creating inventory when it should have worked.")
+				t.Errorf("Error creating ObjMetadata when it should have worked.")
 			} else if test.expected != inv.String() {
 				t.Errorf("Expected inventory (%s) != created inventory(%s)\n", test.expected, inv.String())
 			}