From dcf88baf681e748a6e88fbb4853b4219c83c1fbd Mon Sep 17 00:00:00 2001
From: juehou <juehou@ca.ibm.com>
Date: Tue, 26 Apr 2016 00:35:54 -0400
Subject: [PATCH] Resolver support return promise

---
 common/models/role.js | 14 +++++++++++---
 test/role.test.js     | 15 +++++++++++++++
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/common/models/role.js b/common/models/role.js
index 87bdee06..87a7d24c 100644
--- a/common/models/role.js
+++ b/common/models/role.js
@@ -120,8 +120,9 @@ module.exports = function(Role) {
   /**
    * Add custom handler for roles.
    * @param {String} role Name of role.
-   * @param {Function} resolver Function that determines if a principal is in the specified role.
-   * Signature must be `function(role, context, callback)`
+   * @param {Function} resolver Function that determines
+   * if a principal is in the specified role.
+   * Should provide a callback or return a promise.
    */
   Role.registerResolver = function(role, resolver) {
     if (!Role.resolvers) {
@@ -289,7 +290,14 @@ module.exports = function(Role) {
     var resolver = Role.resolvers[role];
     if (resolver) {
       debug('Custom resolver found for role %s', role);
-      resolver(role, context, callback);
+
+      var promise = resolver(role, context, callback);
+      if (promise && typeof promise.then === 'function') {
+        promise.then(
+          function(result) { callback(null, result); },
+          callback
+        );
+      }
       return;
     }
 
diff --git a/test/role.test.js b/test/role.test.js
index 2129fcb7..8ecddde2 100644
--- a/test/role.test.js
+++ b/test/role.test.js
@@ -8,6 +8,7 @@ var Application = loopback.Application;
 var ACL = loopback.ACL;
 var async = require('async');
 var expect = require('chai').expect;
+var Promise = require('bluebird');
 
 function checkResult(err, result) {
   // console.log(err, result);
@@ -172,6 +173,14 @@ describe('role model', function() {
   });
 
   it('should support owner role resolver', function() {
+    Role.registerResolver('returnPromise', function(role, context) {
+      return new Promise(function(resolve) {
+        process.nextTick(function() {
+          resolve(true);
+        });
+      });
+    });
+
     var Album = ds.createModel('Album', {
       name: String,
       userId: Number,
@@ -186,10 +195,16 @@ describe('role model', function() {
     });
 
     User.create({ name: 'Raymond', email: 'x@y.com', password: 'foobar' }, function(err, user) {
+      Role.isInRole('returnPromise', { principalType: ACL.USER, principalId: user.id },
+      function(err, yes) {
+        assert(!err && yes);
+      });
+
       Role.isInRole(Role.AUTHENTICATED, { principalType: ACL.USER, principalId: user.id },
       function(err, yes) {
         assert(!err && yes);
       });
+
       Role.isInRole(Role.AUTHENTICATED, { principalType: ACL.USER, principalId: null },
       function(err, yes) {
         assert(!err && !yes);