From acdd9622d2ababa4a59ee1d0d04a816791f5d795 Mon Sep 17 00:00:00 2001
From: Victor Woeltjen <victor.woeltjen@nasa.gov>
Date: Mon, 9 Nov 2015 16:51:39 -0800
Subject: [PATCH 1/2] [Topic] Add test case

...which specifies desired behavior for nasa/openmctweb#231.
---
 platform/core/test/services/TopicSpec.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/platform/core/test/services/TopicSpec.js b/platform/core/test/services/TopicSpec.js
index b389b19579..e3732cc240 100644
--- a/platform/core/test/services/TopicSpec.js
+++ b/platform/core/test/services/TopicSpec.js
@@ -65,6 +65,21 @@ define(
                 expect(mockCallback).toHaveBeenCalledWith(testMessage);
             });
 
+            it("is robust against errors thrown by listeners", function () {
+                var mockBadCallback = jasmine.createSpy("bad-callback"),
+                    t = topic();
+
+                mockBadCallback.andCallFake(function () {
+                    throw new Error("I'm afraid I can't do that.");
+                });
+
+                t.listen(mockBadCallback);
+                t.listen(mockCallback);
+
+                t.notify(testMessage);
+                expect(mockCallback).toHaveBeenCalledWith(testMessage);
+            });
+
         });
     }
 );

From e3e44f74d662832dac90a8c3a00805a867eb3ae0 Mon Sep 17 00:00:00 2001
From: Victor Woeltjen <victor.woeltjen@nasa.gov>
Date: Mon, 9 Nov 2015 16:55:22 -0800
Subject: [PATCH 2/2] [Topic] Catch errors from listeners

---
 platform/core/bundle.json                |  3 ++-
 platform/core/src/services/Topic.js      | 10 ++++++++--
 platform/core/test/services/TopicSpec.js |  7 ++++++-
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/platform/core/bundle.json b/platform/core/bundle.json
index 330ac1c2b9..12cedd9a5a 100644
--- a/platform/core/bundle.json
+++ b/platform/core/bundle.json
@@ -207,7 +207,8 @@
             },
             {
                 "key": "topic",
-                "implementation": "services/Topic.js"
+                "implementation": "services/Topic.js",
+                "depends": [ "$log" ]
             },
             {
                 "key": "contextualize",
diff --git a/platform/core/src/services/Topic.js b/platform/core/src/services/Topic.js
index ca38dfcde7..99f042cd43 100644
--- a/platform/core/src/services/Topic.js
+++ b/platform/core/src/services/Topic.js
@@ -26,6 +26,8 @@ define(
     function () {
         "use strict";
 
+        var ERROR_PREFIX = "Error when notifying listener: ";
+
         /**
          * The `topic` service provides a way to create both named,
          * shared listeners and anonymous, private listeners.
@@ -46,7 +48,7 @@ define(
          * @returns {Function}
          * @memberof platform/core
          */
-        function Topic() {
+        function Topic($log) {
             var topics = {};
 
             function createTopic() {
@@ -63,7 +65,11 @@ define(
                     },
                     notify: function (message) {
                         listeners.forEach(function (listener) {
-                            listener(message);
+                            try {
+                                listener(message);
+                            } catch (e) {
+                                $log.error(ERROR_PREFIX + e.message);
+                            }
                         });
                     }
                 };
diff --git a/platform/core/test/services/TopicSpec.js b/platform/core/test/services/TopicSpec.js
index e3732cc240..22865a2571 100644
--- a/platform/core/test/services/TopicSpec.js
+++ b/platform/core/test/services/TopicSpec.js
@@ -28,13 +28,18 @@ define(
 
         describe("The 'topic' service", function () {
             var topic,
+                mockLog,
                 testMessage,
                 mockCallback;
 
             beforeEach(function () {
                 testMessage = { someKey: "some value"};
+                mockLog = jasmine.createSpyObj(
+                    '$log',
+                    [ 'error', 'warn', 'info', 'debug' ]
+                );
                 mockCallback = jasmine.createSpy('callback');
-                topic = new Topic();
+                topic = new Topic(mockLog);
             });
 
             it("notifies listeners on a topic", function () {