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# Cerealizer
# Copyright (C) 2008 Steve Benson, Lann Martin
# Copyright (C) 2012 Jean-Baptiste LAMY
#
# This program is free software.
# It is available under the Python licence.
import datetime
import cerealizer
class DatetimeHandler(cerealizer.Handler):
classname = 'datetime\n'
def dump_obj(self, obj, dumper, s):
assert issubclass(obj.__class__, datetime.datetime)
# This works based on datetime.__reduce__():
# datetime.__reduce__()[1] is a string of bytes that is an internal
# representation of a datetime object (the data field
# PyDateTime_DateTime struct, an unsigned char
# _PyDateTime_DATETIME_DATASIZE bytes long). This should be platform
# independent and is validated upon reconstruction of a datetime.
# Pickle uses it and guarantees backwards compatibility, so
# presumably we can use it here too.
# I haven't verified that tzinfo objects have the same properties,
# which is why they're unsupported right now.
# This string returned by __reduce__ is encoded because it can
# return data that interferes with the cerealizer protocol.
if obj.tzinfo != None:
raise ValueError("DatetimeHandler doesn't yet know how to handle datetime objects with tzinfo.")
s.write('%s%s\n' % (
self.classname,
obj.__reduce__()[1][0].encode('string_escape')
))
def undump_obj(self, dumper, s):
line = s.readline()
if len(line)>0 and line[-1]=='\n':
line = line[:-1]
return datetime.datetime(line.decode('string_escape'))
class DateHandler(cerealizer.Handler):
classname = 'date\n'
def dump_obj(self, obj, dumper, s):
assert issubclass(obj.__class__, datetime.date)
s.write('%s%s\n' % (
self.classname,
obj.__reduce__()[1][0].encode('string_escape')
))
def undump_obj(self, dumper, s):
line = s.readline()
if len(line) > 0 and line[-1] == '\n': line = line[:-1]
return datetime.date(line.decode('string_escape'))
class TimeHandler(cerealizer.Handler):
classname = 'time\n'
def dump_obj(self, obj, dumper, s):
assert issubclass(obj.__class__, datetime.time)
if obj.tzinfo != None:
raise ValueError("DatetimeHandler doesn't yet know how to handle datetime objects with tzinfo.")
s.write('%s%s\n' % (
self.classname,
obj.__reduce__()[1][0].encode('string_escape')
))
def undump_obj(self, dumper, s):
line = s.readline()
if len(line)>0 and line[-1]=='\n':
line = line[:-1]
return datetime.time(line.decode('string_escape'))
cerealizer.register(datetime.datetime, DatetimeHandler())
cerealizer.register(datetime.date , DateHandler ())
cerealizer.register(datetime.time , TimeHandler ())
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