From 9d77ba28d38541b005d39fc9d969a86f0221ac66 Mon Sep 17 00:00:00 2001
From: ryanxwelch <ryan.x.welch@gmail.com>
Date: Mon, 18 Jun 2018 15:13:39 -0400
Subject: [PATCH] Fix crash in verifyUserRelations

In the present implementation `verifyUserRelations(Model)` assumes that
`Model.relations.accessTokens` is always set, and as a result may
crash when trying to access `polymorphic` property of that relation.

It seems the intention is to check whether the the following conditions
are met:
 1. a model has a hasMany accessTokens relation
 2. that relation is polymorphic

This commit fixes the problem by accounting for the case where the
accessTokens relation was not correctly set up.
---
 lib/application.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/application.js b/lib/application.js
index 43965d3a..33239fa3 100644
--- a/lib/application.js
+++ b/lib/application.js
@@ -497,8 +497,10 @@ app._verifyAuthModelRelations = function() {
   function verifyUserRelations(Model) {
     const hasManyTokens = Model.relations && Model.relations.accessTokens;
 
+    const relationsConfig = Model.settings.relations || {};
+    const hasPolyMorphicTokens = (relationsConfig.accessTokens || {}).polymorphic;
     // display a temp warning message for users using multiple users config
-    if (hasManyTokens.polymorphic) {
+    if (hasPolyMorphicTokens) {
       console.warn(
         'The app configuration follows the multiple user models setup ' +
           'as described in http://ibm.biz/setup-loopback-auth',
@@ -508,7 +510,6 @@ app._verifyAuthModelRelations = function() {
 
     if (hasManyTokens) return;
 
-    const relationsConfig = Model.settings.relations || {};
     const accessTokenName = (relationsConfig.accessTokens || {}).model;
     if (accessTokenName) {
       console.warn(