Source code for

"""South Africa-specific Form helpers."""
import re
from datetime import date

from django.forms import ValidationError
from django.forms.fields import CharField, RegexField, Select
from django.utils.translation import gettext_lazy as _
from stdnum import luhn

id_re = re.compile(r'^(?P<yy>\d\d)(?P<mm>\d\d)(?P<dd>\d\d)(?P<mid>\d{4})(?P<end>\d{3})')

[docs]class ZAIDField(CharField): """ A form field for South African ID numbers. The checksum is validated using the Luhn checksum, and uses a simlistic (read: not entirely accurate) check for the birth date. """ default_error_messages = { 'invalid': _('Enter a valid South African ID number'), }
[docs] def clean(self, value): value = super().clean(value) if value in self.empty_values: return value # strip spaces and dashes value = value.replace(' ', '').replace('-', '') match = re.match(id_re, value) if not match: raise ValidationError(self.error_messages['invalid'], code='invalid') g = match.groupdict() try: # The year 2000 is conveniently a leapyear. # This algorithm will break in xx00 years which aren't leap years # There is no way to guess the century of a ZA ID number date(int(g['yy']) + 2000, int(g['mm']), int(g['dd'])) except ValueError: raise ValidationError(self.error_messages['invalid'], code='invalid') if not luhn.is_valid(value): raise ValidationError(self.error_messages['invalid'], code='invalid') return value
[docs]class ZAPostCodeField(RegexField): """ A form field that validates input as a South African postcode. Valid postcodes must have four digits. """ default_error_messages = { 'invalid': _('Enter a valid South African postal code'), } def __init__(self, **kwargs): super().__init__(r'^\d{4}$', **kwargs)
[docs]class ZAProvinceSelect(Select): """A Select widget that uses a list of South African Provinces as its choices.""" def __init__(self, attrs=None): from .za_provinces import PROVINCE_CHOICES super().__init__(attrs, choices=PROVINCE_CHOICES)