#!/usr/bin/env python
##############################################################################
##
# This file is part of Sardana
##
# http://www.sardana-controls.org/
##
# Copyright 2011 CELLS / ALBA Synchrotron, Bellaterra, Spain
##
# Sardana is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
##
# Sardana is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
##
# You should have received a copy of the GNU Lesser General Public License
# along with Sardana. If not, see <http://www.gnu.org/licenses/>.
##
##############################################################################
"""This module is part of the Python Sardana libray. It defines the base class
for Sardana manager"""
__all__ = ["SardanaElementManager", "SardanaIDManager"]
__docformat__ = 'restructuredtext'
from taurus.core.util.codecs import CodecFactory
from sardana import InvalidId
[docs]class SardanaElementManager(object):
"""A class capable of manage elements"""
SerializationProtocol = 'json'
[docs] def get_serialization_protocol(self):
return self.SerializationProtocol
[docs] def set_serialization_protocol(self, protocol):
self.SerializationProtocol = protocol
serialization_protocol = property(get_serialization_protocol,
set_serialization_protocol,
doc="the serialization protocol")
[docs] def serialize_element(self, element, *args, **kwargs):
obj = element.serialize(*args, **kwargs)
return self.serialize_object(obj)
[docs] def serialize_object(self, obj, *args, **kwargs):
return CodecFactory().encode(self.serialization_protocol, ('', obj),
*args, **kwargs)[1]
[docs] def str_element(self, element, *args, **kwargs):
obj = element.serialize(*args, **kwargs)
return self.str_object(obj)
[docs] def str_object(self, obj, *args, **kwargs):
# TODO: use the active codec instead of hardcoded json
return CodecFactory().encode('json', ('', obj), *args, **kwargs)[1]
class SardanaIDManager(object):
"""A class capable of manage ids"""
_last_id = InvalidId
def get_new_id(self):
"""Returns a new ID. The ID becomes reserved at this moment.
:return: a new ID
:rtype: int"""
self._last_id += 1
return self._last_id
def rollback_id(self):
"""Free previously reserved ID"""
self._last_id -= 1
def reserve_id(self, nid):
"""Marks the given ID as reserved
:param id: the ID to be reserved
:type id: int"""
assert isinstance(nid, int)
if nid > self._last_id:
self._last_id = nid