modules/ticket/back/methods/ticket/priceDifference.js

@@ -1,3 +1,5 @@
+const UserError = require('vn-loopback/util/user-error');
+
 module.exports = Self => {
     Self.remoteMethodCtx('priceDifference', {
         description: 'Returns sales with price difference if the ticket is editable',