Allow HTTP code without an explicit error

errors/errors.go

@@ -74,10 +74,6 @@ func Wrap(err error, msg string) error {
 }
 
 func HTTP(code int, err error, format string, args ...interface{}) error {
-	if err == nil {
-		return nil
-	}
-
 	wrappedErr := &CustomError{
 		code:    code,
 		message: fmt.Sprintf(format, args...),
@@ -101,6 +97,10 @@ func HTTPWithMsg(code int, format string, args ...interface{}) error {
 	return wrappedErr
 }
 
+func HTTPCodeOnly(code int) error {
+	return HTTP(code, nil, "")
+}
+
 func HTTPWithError(code int, err error) error {
 	wrappedErr := &CustomError{
 		code:    code,