Merge pull request #7389 from minrk/one-websocket

use single WebSocket connection for all channels

IPython/html/base/zmqhandlers.py

@@ -138,7 +138,7 @@ def clear_cookie(self, *args, **kwargs):
         """meaningless for websockets"""
         pass
 
-    def _reserialize_reply(self, msg_list):
+    def _reserialize_reply(self, msg_list, channel=None):
         """Reserialize a reply message using JSON.
 
         This takes the msg list from the ZMQ socket, deserializes it using
@@ -148,19 +148,22 @@ def _reserialize_reply(self, msg_list):
         """
         idents, msg_list = self.session.feed_identities(msg_list)
         msg = self.session.deserialize(msg_list)
+        if channel:
+            msg['channel'] = channel
         if msg['buffers']:
             buf = serialize_binary_message(msg)
             return buf
         else:
             smsg = json.dumps(msg, default=date_default)
             return cast_unicode(smsg)
 
-    def _on_zmq_reply(self, msg_list):
+    def _on_zmq_reply(self, stream, msg_list):
         # Sometimes this gets triggered when the on_close method is scheduled in the
         # eventloop but hasn't been called.
-        if self.stream.closed(): return
+        if stream.closed(): return
+        channel = getattr(stream, 'channel', None)
         try:
-            msg = self._reserialize_reply(msg_list)
+            msg = self._reserialize_reply(msg_list, channel=channel)
         except Exception:
             self.log.critical("Malformed message: %r" % msg_list, exc_info=True)
         else:

IPython/html/services/kernels/handlers.py

@@ -84,7 +84,7 @@ def post(self, kernel_id, action):
         self.finish()
 
 
-class ZMQChannelHandler(AuthenticatedZMQStreamHandler):
+class ZMQChannelsHandler(AuthenticatedZMQStreamHandler):
 
     @property
     def kernel_info_timeout(self):
@@ -95,8 +95,13 @@ def __repr__(self):
 
     def create_stream(self):
         km = self.kernel_manager
-        meth = getattr(km, 'connect_%s' % self.channel)
-        self.zmq_stream = meth(self.kernel_id, identity=self.session.bsession)
+        identity = self.session.bsession
+        for channel in ('shell', 'iopub', 'stdin'):
+            meth = getattr(km, 'connect_' + channel)
+            self.channels[channel] = stream = meth(self.kernel_id, identity=identity)
+            stream.channel = channel
+        km.add_restart_callback(self.kernel_id, self.on_kernel_restarted)
+        km.add_restart_callback(self.kernel_id, self.on_restart_failed, 'dead')
 
     def request_kernel_info(self):
         """send a request for kernel_info"""
@@ -160,16 +165,17 @@ def _finish_kernel_info(self, info):
             self._kernel_info_future.set_result(info)
 
     def initialize(self):
-        super(ZMQChannelHandler, self).initialize()
+        super(ZMQChannelsHandler, self).initialize()
         self.zmq_stream = None
+        self.channels = {}
         self.kernel_id = None
         self.kernel_info_channel = None
         self._kernel_info_future = Future()
 
     @gen.coroutine
     def pre_get(self):
         # authenticate first
-        super(ZMQChannelHandler, self).pre_get()
+        super(ZMQChannelsHandler, self).pre_get()
         # then request kernel info, waiting up to a certain time before giving up.
         # We don't want to wait forever, because browsers don't take it well when
         # servers never respond to websocket connection requests.
@@ -189,56 +195,36 @@ def give_up():
     @gen.coroutine
     def get(self, kernel_id):
         self.kernel_id = cast_unicode(kernel_id, 'ascii')
-        yield super(ZMQChannelHandler, self).get(kernel_id=kernel_id)
+        yield super(ZMQChannelsHandler, self).get(kernel_id=kernel_id)
 
     def open(self, kernel_id):
-        super(ZMQChannelHandler, self).open()
+        super(ZMQChannelsHandler, self).open()
         try:
             self.create_stream()
         except web.HTTPError as e:
             self.log.error("Error opening stream: %s", e)
             # WebSockets don't response to traditional error codes so we
             # close the connection.
-            if not self.stream.closed():
-                self.stream.close()
+            for channel, stream in self.channels.items():
+                if not stream.closed():
+                    stream.close()
             self.close()
         else:
-            self.zmq_stream.on_recv(self._on_zmq_reply)
+            for channel, stream in self.channels.items():
+                stream.on_recv_stream(self._on_zmq_reply)
 
     def on_message(self, msg):
-        if self.zmq_stream is None:
-            return
-        elif self.zmq_stream.closed():
-            self.log.info("%s closed, closing websocket.", self)
-            self.close()
-            return
         if isinstance(msg, bytes):
             msg = deserialize_binary_message(msg)
         else:
             msg = json.loads(msg)
-        self.session.send(self.zmq_stream, msg)
+        channel = msg.pop('channel', None)
+        if channel is None:
+            self.log.warn("No channel specified, assuming shell: %s", msg)
+            channel = 'shell'
+        stream = self.channels[channel]
+        self.session.send(stream, msg)
 
-    def on_close(self):
-        # This method can be called twice, once by self.kernel_died and once
-        # from the WebSocket close event. If the WebSocket connection is
-        # closed before the ZMQ streams are setup, they could be None.
-        if self.zmq_stream is not None and not self.zmq_stream.closed():
-            self.zmq_stream.on_recv(None)
-            # close the socket directly, don't wait for the stream
-            socket = self.zmq_stream.socket
-            self.zmq_stream.close()
-            socket.close()
-
-
-class IOPubHandler(ZMQChannelHandler):
-    channel = 'iopub'
-
-    def create_stream(self):
-        super(IOPubHandler, self).create_stream()
-        km = self.kernel_manager
-        km.add_restart_callback(self.kernel_id, self.on_kernel_restarted)
-        km.add_restart_callback(self.kernel_id, self.on_restart_failed, 'dead')
-
     def on_close(self):
         km = self.kernel_manager
         if self.kernel_id in km:
@@ -248,12 +234,24 @@ def on_close(self):
             km.remove_restart_callback(
                 self.kernel_id, self.on_restart_failed, 'dead',
             )
-        super(IOPubHandler, self).on_close()
-
+        # This method can be called twice, once by self.kernel_died and once
+        # from the WebSocket close event. If the WebSocket connection is
+        # closed before the ZMQ streams are setup, they could be None.
+        for channel, stream in self.channels.items():
+            if stream is not None and not stream.closed():
+                stream.on_recv(None)
+                # close the socket directly, don't wait for the stream
+                socket = stream.socket
+                stream.close()
+                socket.close()
+
+        self.channels = {}
+
     def _send_status_message(self, status):
         msg = self.session.msg("status",
             {'execution_state': status}
         )
+        msg['channel'] = 'iopub'
         self.write_message(json.dumps(msg, default=date_default))
 
     def on_kernel_restarted(self):
@@ -263,18 +261,6 @@ def on_kernel_restarted(self):
     def on_restart_failed(self):
         logging.error("kernel %s restarted failed!", self.kernel_id)
         self._send_status_message('dead')
-
-    def on_message(self, msg):
-        """IOPub messages make no sense"""
-        pass
-
-
-class ShellHandler(ZMQChannelHandler):
-    channel = 'shell'
-
-
-class StdinHandler(ZMQChannelHandler):
-    channel = 'stdin'
 
 
 #-----------------------------------------------------------------------------
@@ -289,7 +275,5 @@ class StdinHandler(ZMQChannelHandler):
     (r"/api/kernels", MainKernelHandler),
     (r"/api/kernels/%s" % _kernel_id_regex, KernelHandler),
     (r"/api/kernels/%s/%s" % (_kernel_id_regex, _kernel_action_regex), KernelActionHandler),
-    (r"/api/kernels/%s/iopub" % _kernel_id_regex, IOPubHandler),
-    (r"/api/kernels/%s/shell" % _kernel_id_regex, ShellHandler),
-    (r"/api/kernels/%s/stdin" % _kernel_id_regex, StdinHandler)
+    (r"/api/kernels/%s/channels" % _kernel_id_regex, ZMQChannelsHandler),
 ]