baseimage-tutorial-framework/tfw/internals/networking/zmq_connector.py

75 lines
2.4 KiB
Python

import logging
import zmq
from zmq.eventloop.zmqstream import ZMQStream
from .scope import Scope
from .serialization import (
serialize_tfw_msg,
deserialize_tfw_msg,
with_deserialize_tfw_msg
)
LOG = logging.getLogger(__name__)
class ZMQDownlinkConnector:
def __init__(self, connect_addr):
self._zmq_sub_socket = zmq.Context.instance().socket(zmq.SUB)
self._zmq_sub_socket.setsockopt(zmq.RCVHWM, 0)
self._zmq_sub_socket.connect(connect_addr)
self._zmq_sub_stream = ZMQStream(self._zmq_sub_socket)
def subscribe(self, *keys):
for key in keys:
self._zmq_sub_socket.setsockopt_string(zmq.SUBSCRIBE, key)
def unsubscribe(self, *keys):
for key in keys:
self._zmq_sub_socket.setsockopt_string(zmq.UNSUBSCRIBE, key)
def register_callback(self, callback):
callback = with_deserialize_tfw_msg(callback) if callback else None
self._zmq_sub_stream.on_recv(callback)
def recv_message(self, *, block=True):
if self._zmq_sub_stream.receiving():
raise RuntimeError('Synchronous recv() called while a callback is registered!')
flags = 0 if block else zmq.NOBLOCK
try:
return deserialize_tfw_msg(*self._zmq_sub_socket.recv_multipart(flags))
except zmq.ZMQError:
raise IOError("No data available to recv!")
def close(self):
self._zmq_sub_stream.close()
class ZMQUplinkConnector:
def __init__(self, connect_addr):
self._zmq_push_socket = zmq.Context.instance().socket(zmq.PUSH)
self._zmq_push_socket.setsockopt(zmq.SNDHWM, 0)
self._zmq_push_socket.connect(connect_addr)
def send_message(self, message, scope=None, intent=None):
if 'scope' not in message:
message['scope'] = Scope.ZMQ.value
if scope is not None:
message['scope'] = scope.value
if intent is not None:
message['intent'] = intent.value
self._zmq_push_socket.send_multipart(serialize_tfw_msg(message))
def close(self):
self._zmq_push_socket.close()
class ZMQConnector(ZMQDownlinkConnector, ZMQUplinkConnector):
def __init__(self, downlink_connect_addr, uplink_connect_addr):
ZMQDownlinkConnector.__init__(self, downlink_connect_addr)
ZMQUplinkConnector.__init__(self, uplink_connect_addr)
def close(self):
ZMQDownlinkConnector.close(self)
ZMQUplinkConnector.close(self)