+
−#!/usr/bin/python2.5
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−#
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−# Copyright 2009 the Melange authors.
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−#
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−# Licensed under the Apache License, Version 2.0 (the "License");
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−# you may not use this file except in compliance with the License.
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−# You may obtain a copy of the License at
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−#
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−#   http://www.apache.org/licenses/LICENSE-2.0
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−#
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−# Unless required by applicable law or agreed to in writing, software
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−# distributed under the License is distributed on an "AS IS" BASIS,
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−# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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−# See the License for the specific language governing permissions and
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−# limitations under the License.
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−
+
−"""Functions that are useful when dealing with timelines.
+
−"""
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−
+
−__authors__ = [
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−  '"Lennard de Rijk" <ljvderijk@gmail.com>',
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−  ]
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−
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−
+
−import datetime
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−
+
−
+
−def isBeforePeriod(entity, period):
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−  """Returns true iff the current DateTime is before the given period_start.
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−
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−  Args:
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−    entity: Instance of a timeline model.
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−    period: The name of a period (without start or end).
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−  """
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−
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−  return isBeforeEvent(entity, '%s_start' % period)
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−
+
−
+
−def isBeforeEvent(entity, event):
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−  """Returns true iff the current DateTime is before the given event.
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−
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−  Args:
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−    entity: Instance of a timeline model.
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−    event: The name of property in the timeline model.
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−  """
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−  event_time = getDateTimeByName(entity, event)
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−
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−  if event_time:
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−    return datetime.datetime.utcnow() < event_time
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−  else:
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−    return False
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−
+
−
+
−def isActivePeriod(entity, period):
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−  """Returns true iff the current DateTime is between period_start 
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−     and period_end.
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−
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−  Args:
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−    entity: Instance of a timeline model.
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−    period: The name of a period (without start or end).
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−  """
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−
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−  period_start = '%s_start' % period
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−  period_end = '%s_end' % period
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−
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−  period_started = isAfterEvent(entity, period_start)
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−  period_not_ended = isBeforeEvent(entity, period_end)
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−
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−  return period_started and period_not_ended
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−
+
−
+
−def isAfterPeriod(entity, period):
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−  """Returns true iff the current DateTime is after the given period_end.
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−
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−  Args:
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−    entity: Instance of a timeline model.
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−    period: The name of a period (without start or end).
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−  """
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−
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−  return isAfterEvent(entity, '%s_end' % period)
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−
+
−
+
−def isAfterEvent(entity, event):
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−  """Returns true iff the current DateTime is after the given event.
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−
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−  Args:
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−    entity: Instance of a timeline model.
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−    event: The name of property in the timeline model.
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−  """
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−  event_time = getDateTimeByName(entity, event)
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−
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−  if event_time:
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−    return event_time < datetime.datetime.utcnow()
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−  else:
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−    return False
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−
+
−
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−def getDateTimeByName(entity, name):
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−  """Returns the DateTime property with the given name. 
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−
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−  Args:
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−    entity: Instance of a timeline model.
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−    name: The name of a specific property in the given timeline model.
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−
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−  Returns:
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−    The requested DateTime property, or None if there is no such property set.
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−  """
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−
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−  if hasattr(entity, name):
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−    return getattr(entity, name)
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−  else:
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−    return None