Source code for rocon_scheduler_requests.common

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"""
.. module:: common

This module provides some common definitions for the ROCON resource
scheduler, part of the `Robotics in Concert`_ project.

.. _`Robotics in Concert`: http://www.robotconcert.org/wiki/Main_Page
.. _UUID: http://en.wikipedia.org/wiki/Uuid

"""

# (unicode_literals not compatible with python2 uuid module)
from __future__ import absolute_import, print_function

HEARTBEAT_HZ = 1.0 / 4.0
""" Default requester heartbeat frequency (Hz)."""

SCHEDULER_TOPIC = 'rocon_scheduler'
""" Default ROCON scheduler topic name. """


def feedback_topic(uuid, scheduler_topic=SCHEDULER_TOPIC):
    """ Construct scheduler feedback topic name.

    :param uuid: UUID_ of the requester.
    :type uuid: :class:`uuid.UUID`

    :param topic: Topic name for the corresponding scheduler. If
                  missing, the usual scheduler topic name is assumed.
    :type topic: str
    :returns: Topic name string for replying to this requester.

    """
    return scheduler_topic + '_' + uuid.hex