Fixed bug viewing unassigned task without modification rights.

attract/tasks/routes.py

@@ -71,8 +71,13 @@ def view_task(project, attract_props, task_id):
         users = project.get_users(api=api)
         project.users = users['_items']
     else:
-        task.properties.assigned_to.users = [pillar.web.subquery.get_user_info(uid)
-                                             for uid in task.properties.assigned_to.users]
+        try:
+            user_ids = task.properties.assigned_to.users
+        except AttributeError:
+            task.properties['assigned_to'] = {'users': []}
+        else:
+            task.properties.assigned_to.users = [pillar.web.subquery.get_user_info(uid)
+                                                 for uid in user_ids]
 
     return render_template('attract/tasks/view_task_embed.html',
                            task=task,