Files
account-financial-tools/currency_rate_update/services/update_service_ECB.py
2014-11-19 14:07:41 +02:00

104 lines
4.4 KiB
Python

# -*- coding: utf-8 -*-
##############################################################################
#
# Copyright (c) 2009 CamptoCamp. All rights reserved.
# @author Nicolas Bessi
#
# Abstract class to fetch rates from European Central Bank
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program 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 Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
##############################################################################
from .currency_getter_interface import Currency_getter_interface
from datetime import datetime
from openerp.tools import DEFAULT_SERVER_DATE_FORMAT
import logging
_logger = logging.getLogger(__name__)
class ECB_getter(Currency_getter_interface):
"""Implementation of Currency_getter_factory interface
for ECB service
"""
def rate_retrieve(self, dom, ns, curr):
"""Parse a dom node to retrieve-
currencies data
"""
res = {}
xpath_curr_rate = ("/gesmes:Envelope/def:Cube/def:Cube/"
"def:Cube[@currency='%s']/@rate") % (curr.upper())
res['rate_currency'] = float(
dom.xpath(xpath_curr_rate, namespaces=ns)[0]
)
return res
def get_updated_currency(self, currency_array, main_currency,
max_delta_days):
"""implementation of abstract method of Curreny_getter_interface"""
url = 'http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml'
# Important : as explained on the ECB web site, the currencies are
# at the beginning of the afternoon ; so, until 3 p.m. Paris time
# the currency rates are the ones of trading day N-1
# http://www.ecb.europa.eu/stats/exchange/eurofxref/html/index.en.html
# We do not want to update the main currency
if main_currency in currency_array:
currency_array.remove(main_currency)
# Move to new XML lib cf Launchpad bug #645263
from lxml import etree
_logger.debug("ECB currency rate service : connecting...")
rawfile = self.get_url(url)
dom = etree.fromstring(rawfile)
_logger.debug("ECB sent a valid XML file")
ecb_ns = {
'gesmes': 'http://www.gesmes.org/xml/2002-08-01',
'def': 'http://www.ecb.int/vocabulary/2002-08-01/eurofxref'
}
rate_date = dom.xpath('/gesmes:Envelope/def:Cube/def:Cube/@time',
namespaces=ecb_ns)[0]
rate_date_datetime = datetime.strptime(rate_date,
DEFAULT_SERVER_DATE_FORMAT)
self.check_rate_date(rate_date_datetime, max_delta_days)
# We dynamically update supported currencies
self.supported_currency_array = dom.xpath(
"/gesmes:Envelope/def:Cube/def:Cube/def:Cube/@currency",
namespaces=ecb_ns
)
self.supported_currency_array.append('EUR')
_logger.debug("Supported currencies = %s " %
self.supported_currency_array)
self.validate_cur(main_currency)
if main_currency != 'EUR':
main_curr_data = self.rate_retrieve(dom, ecb_ns, main_currency)
for curr in currency_array:
self.validate_cur(curr)
if curr == 'EUR':
rate = 1 / main_curr_data['rate_currency']
else:
curr_data = self.rate_retrieve(dom, ecb_ns, curr)
if main_currency == 'EUR':
rate = curr_data['rate_currency']
else:
rate = (curr_data['rate_currency'] /
main_curr_data['rate_currency'])
self.updated_currency[curr] = rate
_logger.debug(
"Rate retrieved : 1 %s = %s %s" % (main_currency, rate, curr)
)
return self.updated_currency, self.log_info