openmedialibrary_platform/Shared/lib/python2.7/site-packages/stdnum/eu/vat.py
2014-05-16 01:20:41 +02:00

130 lines
4.6 KiB
Python

# vat.py - functions for handling European VAT numbers
# coding: utf-8
#
# Copyright (C) 2012, 2013 Arthur de Jong
#
# This library 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 2.1 of the License, or (at your option) any later version.
#
# This library 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 this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301 USA
"""VAT (European Union VAT number).
The European Union VAT number consists of a 2 letter country code (ISO
3166-1, except Greece which uses EL) followed by a number that is
allocated per country.
The exact format of the numbers varies per country and a country-specific
check is performed on the number using the VAT module that is relevant for
that country.
>>> compact('ATU 57194903')
'ATU57194903'
>>> validate('BE697449992')
'BE0697449992'
>>> validate('FR 61 954 506 077')
'FR61954506077'
>>> guess_country('00449544B01')
['nl']
"""
from stdnum.exceptions import *
from stdnum.util import clean
country_codes = set([
'at', 'be', 'bg', 'cy', 'cz', 'de', 'dk', 'ee', 'es', 'fi', 'fr', 'gb',
'gr', 'hu', 'ie', 'it', 'lt', 'lu', 'lv', 'mt', 'nl', 'pl', 'pt', 'ro',
'se', 'si', 'sk'
])
"""The collection of country codes that are queried. Greece is listed with
a country code of gr while for VAT purposes el is used instead."""
_country_modules = dict()
vies_wsdl = 'http://ec.europa.eu/taxation_customs/vies/checkVatService.wsdl'
"""The WSDL URL of the VAT Information Exchange System (VIES)."""
# a cached version of the suds client for VIES
_vies_client = None
def _get_cc_module(cc):
"""Get the VAT number module based on the country code."""
# Greece uses a "wrong" country code
cc = cc.lower()
if cc == 'el':
cc = 'gr'
if cc not in country_codes:
return
if cc not in _country_modules:
# do `from stdnum.CC import vat` instead of `import stdnum.CC.vat`
# to handle the case where vat is an alias
_country_modules[cc] = __import__(
'stdnum.%s' % cc, globals(), locals(), ['vat']).vat
return _country_modules[cc]
def compact(number):
"""Convert the number to the minimal representation. This strips the
number of any valid separators and removes surrounding whitespace."""
number = clean(number, '').upper().strip()
module = _get_cc_module(number[:2])
if not module:
raise InvalidComponent()
return number[:2] + module.compact(number[2:])
def validate(number):
"""Checks to see if the number provided is a valid VAT number. This
performs the country-specific check for the number."""
number = clean(number, '').upper().strip()
module = _get_cc_module(number[:2])
if not module:
raise InvalidComponent()
return number[:2] + module.validate(number[2:])
def is_valid(number):
"""Checks to see if the number provided is a valid VAT number. This
performs the country-specific check for the number."""
try:
return bool(validate(number))
except ValidationError:
return False
def guess_country(number):
"""Guess the country code based on the provided number. This checks the
provided number against each of the validation routines and returns
the list of countries for which it is valid. This returns lower case
codes and returns gr (not el) for Greece."""
return [cc
for cc in country_codes
if _get_cc_module(cc).is_valid(number)]
def check_vies(number): # pragma: no cover (no tests for this function)
"""Queries the online European Commission VAT Information Exchange
System (VIES) for validity of the provided number. Note that the
service has usage limitations (see the VIES website for details).
This returns a dict-like object."""
# this function isn't automatically tested because it would require
# network access for the tests and unnecessarily load the VIES website
number = compact(number)
global _vies_client
if not _vies_client:
from suds.client import Client
from urllib import getproxies
_vies_client = Client(vies_wsdl, proxy=getproxies())
return _vies_client.service.checkVat(number[:2], number[2:])