http: Handle getting correct IOLoop when running on tornado < 3.0

docs/changelog.rst

@@ -4,6 +4,14 @@ Changelog
 
 This changelog is used to track all major changes to Mopidy.
 
+v1.0.2 (unreleased)
+===================
+
+Bug fix release.
+
+- HTTP: Make event broadcasts work with Tornado 2.3, the previous threading fix
+  broke this.
+
 
 v1.0.1 (2015-04-23)
 ===================

mopidy/http/handlers.py

@@ -88,9 +88,13 @@ class WebSocketHandler(tornado.websocket.WebSocketHandler):
 
     @classmethod
     def broadcast(cls, msg):
+        if hasattr(tornado.ioloop.IOLoop, 'current'):
+            loop = tornado.ioloop.IOLoop.current()
+        else:
+            loop = tornado.ioloop.IOLoop.instance()  # Fallback for 2.3
+
         # This can be called from outside the Tornado ioloop, so we need to
         # safely cross the thread boundary by adding a callback to the loop.
-        loop = tornado.ioloop.IOLoop.current()
         for client in cls.clients:
             # One callback per client to keep time we hold up the loop short
             loop.add_callback(_send_broadcast, client, msg)