class Channel(object):
"""Mother of all channels. Defines the interface.
Callbacks:
The callbacks will receive the channel as first parameter and
the message as second parameter. The error callback will get
the stream where the error occured as second parameter.
Attributes:
* stream_in, stream_out : the streams for eventlopp handling
* serializer : the serializer used
"""
def __init__(self, socket_in, socket_out, serializer):
self.stream_in = ZMQStream(socket_in)
self.stream_out = ZMQStream(socket_out)
self.serializer = serializer
self._cb_receive = None
self._cb_send = None
self._cb_error = None
self._chan_id = id(self)
return
def on_receive(self, callback):
"""Set callback to invoke when a message was received.
"""
self.stream_in.stop_on_recv()
self._cb_receive = callback
if callback:
self.stream_in.on_recv(self._on_recv)
return
def on_send(self, callback):
"""Set callback to invoke when a message was sent.
"""
self.stream_out.stop_on_send()
self._cb_send = callback
if callback:
self.stream_out.on_send(self._on_send)
return
def on_error(self, callback):
"""Set callback to invoke when an error event occured.
"""
self.stream_in.stop_on_err()
self.stream_out.stop_on_err()
self._cb_error = callback
if callback:
self.stream_in.on_err(self._on_err_in)
self.stream_out.on_err(self._on_err_out)
return
def send(self, message):
"""Send given message.
"""
m = self.serializer.serialize(message)
if self.serializer.multipart:
self.stream_out.send_multipart(m)
else:
self.stream_out.send(m)
return
def _on_recv(self, msg):
"""Helper interfacing w/ streams.
"""
if self.serializer.multipart:
msg = self.serializer.deserialize(msg)
else:
msg = self.serializer.deserialize(msg[0])
self._cb_receive(self, msg)
return
def _on_send(self, sent, _):
"""Helper interfacing w/ streams.
"""
msg = sent[0]
if self.serializer.multipart:
msg = self.serializer.deserialize(msg)
else:
msg = self.serializer.deserialize(msg[0])
self._cb_send(self, msg)
return
def _on_err_in(self):
self._cb_error(self, self.stream_in)
return
def _on_err_out(self):
self._cb_error(self, self.stream_out)
return
def __hash__(self):
return self._chan_id
def __eq__(self, other):
if not isinstance(other, self.__class__):
return False
return self._chan_id == other._chan_id
def __neq__(self, other):
if not isinstance(other, self.__class__):
return True
return self._chan_id != other._chan_id
