# -*- coding: iso-8859-1 -*-
# $Id: TimedeltaField.py 1787 2011-04-20 07:09:57Z tguettler $
# $HeadURL: svn+ssh://svnserver/svn/djangotools/trunk/dbfields/TimedeltaField.py $
# http://djangosnippets.org/snippets/1060/
# Python
import datetime
# Django
from django import forms
from django.db import models
from django.utils.safestring import mark_safe
from django.utils.translation import ugettext_lazy as _
#Djangotools
from djangotools.utils.southutils import add_introspection_rules_from_baseclass
SECS_PER_DAY=3600*24
class TimedeltaField(models.Field):
u'''
Store Python's datetime.timedelta in an integer column.
Most databasesystems only support 32 Bit integers by default.
'''
__metaclass__=models.SubfieldBase
def __init__(self, *args, **kwargs):
super(TimedeltaField, self).__init__(*args, **kwargs)
def to_python(self, value):
if (value is None) or isinstance(value, datetime.timedelta):
return value
assert isinstance(value, int), (value, type(value))
return datetime.timedelta(seconds=value)
def get_internal_type(self):
return 'IntegerField'
def get_db_prep_lookup(self, lookup_type, value, connection=None, prepared=False):
raise NotImplementedError() # SQL WHERE
def get_db_prep_save(self, value, connection=None, prepared=False):
if (value is None) or isinstance(value, int):
return value
return SECS_PER_DAY*value.days+value.seconds
def formfield(self, *args, **kwargs):
defaults={'form_class': TimedeltaFormField}
defaults.update(kwargs)
return super(TimedeltaField, self).formfield(*args, **defaults)
def value_to_string(self, obj):
value = self._get_val_from_obj(obj)
return self.get_db_prep_value(value)
#South Plugin registrieren
add_introspection_rules_from_baseclass(TimedeltaField, ["^djangotools\.dbfields\.TimedeltaField"])
class TimedeltaFormField(forms.Field):
default_error_messages = {
'invalid': _(u'Enter a whole number.'),
}
def __init__(self, *args, **kwargs):
defaults={'widget': TimedeltaWidget}
defaults.update(kwargs)
super(TimedeltaFormField, self).__init__(*args, **defaults)
def clean(self, value):
# value comes from Timedelta.Widget.value_from_datadict(): tuple of strings
super(TimedeltaFormField, self).clean(value)
assert len(value)==len(self.widget.inputs), (value, self.widget.inputs)
i=0
for value, multiply in zip(value, self.widget.multiply):
try:
i+=int(value)*multiply
except ValueError, TypeError:
raise forms.ValidationError(self.error_messages['invalid'])
return i
class TimedeltaWidget(forms.Widget):
INPUTS=['days', 'hours', 'minutes', 'seconds']
MULTIPLY=[60*60*24, 60*60, 60, 1]
def __init__(self, attrs=None):
self.widgets=[]
if not attrs:
attrs={}
inputs=attrs.get('inputs', self.INPUTS)
multiply=[]
for input in inputs:
assert input in self.INPUTS, (input, self.INPUT)
self.widgets.append(forms.TextInput(attrs=attrs))
multiply.append(self.MULTIPLY[self.INPUTS.index(input)])
self.inputs=inputs
self.multiply=multiply
super(TimedeltaWidget, self).__init__(attrs)
def render(self, name, value, attrs):
if value is None:
values=[0 for i in self.inputs]
elif isinstance(value, datetime.timedelta):
values=split_seconds(value.days*SECS_PER_DAY+value.seconds, self.inputs, self.multiply)
elif isinstance(value, int):
# initial data from model
values=split_seconds(value, self.inputs, self.multiply)
else:
assert isinstance(value, tuple), (value, type(value))
assert len(value)==len(self.inputs), (value, self.inputs)
values=value
id=attrs.pop('id')
assert not attrs, attrs
rendered=[]
for input, widget, val in zip(self.inputs, self.widgets, values):
rendered.append(u'%s %s' % (_(input), widget.render('%s_%s' % (name, input), val)))
return mark_safe('<div id="%s">%s</div>' % (id, ' '.join(rendered)))
def value_from_datadict(self, data, files, name):
# Don't throw ValidationError here, just return a tuple of strings.
ret=[]
for input, multi in zip(self.inputs, self.multiply):
ret.append(data.get('%s_%s' % (name, input), 0))
return tuple(ret)
def _has_changed(self, initial_value, data_value):
# data_value comes from value_from_datadict(): A tuple of strings.
if initial_value is None:
return bool(set(data_value)!=set([u'0']))
assert isinstance(initial_value, datetime.timedelta), initial_value
initial=tuple([unicode(i) for i in split_seconds(initial_value.days*SECS_PER_DAY+initial_value.seconds, self.inputs, self.multiply)])
assert len(initial)==len(data_value), (initial, data_value)
return bool(initial!=data_value)
def main():
assert split_seconds(1000000)==[11, 13, 46, 40]
field=TimedeltaField()
td=datetime.timedelta(days=10, seconds=11)
s=field.get_db_prep_save(td)
assert isinstance(s, int), (s, type(s))
td_again=field.to_python(s)
assert td==td_again, (td, td_again)
td=datetime.timedelta(seconds=11)
s=field.get_db_prep_save(td)
td_again=field.to_python(s)
assert td==td_again, (td, td_again)
field=TimedeltaFormField()
assert field.widget._has_changed(datetime.timedelta(seconds=0), (u'0', u'0', u'0', u'0',)) is False
assert field.widget._has_changed(None, (u'0', u'0', u'0', u'0',)) is False
assert field.widget._has_changed(None, (u'0', u'0')) is False
assert field.widget._has_changed(datetime.timedelta(days=1, hours=2, minutes=3, seconds=4), (u'1', u'2', u'3', u'4',)) is False
for secs, soll, kwargs in [
(100, [0, 0, 1, 40], dict()),
(100, ['0days', '0hours', '1minutes', '40seconds'], dict(with_unit=True)),
(100, ['1minutes', '40seconds'], dict(with_unit=True, remove_leading_zeros=True)),
(100000, ['1days', '3hours'], dict(inputs=['days', 'hours'], with_unit=True, remove_leading_zeros=True)),
]:
ist=split_seconds(secs, **kwargs)
if ist!=soll:
raise Exception('geg=%s soll=%s ist=%s kwargs=%s' % (secs, soll, ist, kwargs))
print "unittest OK"
def split_seconds(secs, inputs=TimedeltaWidget.INPUTS, multiply=TimedeltaWidget.MULTIPLY,
with_unit=False, remove_leading_zeros=False):
ret=[]
assert len(inputs)<=len(multiply), (inputs, multiply)
for input, multi in zip(inputs, multiply):
count, secs = divmod(secs, multi)
if remove_leading_zeros and not ret and not count:
continue
if with_unit:
ret.append('%s%s' % (count, input))
else:
ret.append(count)
return ret
if __name__=='__main__':
main()