69 lines
2 KiB
Python
69 lines
2 KiB
Python
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# -*- coding: utf-8 -*-
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"""Module holding utility and convenience functions for zmq event monitoring."""
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# Copyright (C) PyZMQ Developers
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# Distributed under the terms of the Modified BSD License.
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import struct
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import zmq
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from zmq.error import _check_version
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def parse_monitor_message(msg):
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"""decode zmq_monitor event messages.
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Parameters
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----------
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msg : list(bytes)
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zmq multipart message that has arrived on a monitor PAIR socket.
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First frame is::
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16 bit event id
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32 bit event value
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no padding
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Second frame is the endpoint as a bytestring
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Returns
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-------
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event : dict
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event description as dict with the keys `event`, `value`, and `endpoint`.
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"""
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if len(msg) != 2 or len(msg[0]) != 6:
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raise RuntimeError("Invalid event message format: %s" % msg)
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event = {'event': struct.unpack("=hi", msg[0])[0],
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'value': struct.unpack("=hi", msg[0])[1],
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'endpoint': msg[1]}
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return event
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def recv_monitor_message(socket, flags=0):
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"""Receive and decode the given raw message from the monitoring socket and return a dict.
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Requires libzmq ≥ 4.0
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The returned dict will have the following entries:
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event : int, the event id as described in libzmq.zmq_socket_monitor
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value : int, the event value associated with the event, see libzmq.zmq_socket_monitor
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endpoint : string, the affected endpoint
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Parameters
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----------
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socket : zmq PAIR socket
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The PAIR socket (created by other.get_monitor_socket()) on which to recv the message
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flags : bitfield (int)
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standard zmq recv flags
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Returns
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-------
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event : dict
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event description as dict with the keys `event`, `value`, and `endpoint`.
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"""
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_check_version((4,0), 'libzmq event API')
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# will always return a list
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msg = socket.recv_multipart(flags)
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# 4.0-style event API
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return parse_monitor_message(msg)
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__all__ = ['parse_monitor_message', 'recv_monitor_message']
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