investment/rate.py

# -*- coding: utf-8 -*-
# This file is part of the investment-module from m-ds.de for Tryton.
# The COPYRIGHT file at the top level of this repository contains the
# full copyright notices and license terms.

from trytond.model import ModelView, ModelSQL, fields, Unique, Check, SymbolMixin
from trytond.transaction import Transaction
from trytond.pool import Pool
from trytond.pyson import Eval, Bool


class Rate(SymbolMixin, ModelSQL, ModelView):
    'Rate'
    __name__ = 'investment.rate'

    asset = fields.Many2One(string='Asset', required=True,
        select=True, ondelete='CASCADE',
        model_name='investment.asset')
    date = fields.Date(string='Date', required=True, select=True)
    rate = fields.Numeric(string='Rate', required=True,
        digits=(16, Eval('asset_digits', 4)),
        depends=['asset_digits'])

    asset_digits = fields.Function(fields.Integer(string='Digits',
        readonly=True), 'get_rate_data')
    currency = fields.Function(fields.Many2One(string='Currency',
        readonly=True, model_name='currency.currency'),
        'get_rate_data')
    uom = fields.Function(fields.Many2One(string='Uom',
        readonly=True, model_name='product.uom'), 'get_rate_data')
    symbol = fields.Function(fields.Char(string='Symbol',
        readonly=True), 'get_rate_data')

    @classmethod
    def __setup__(cls):
        super(Rate, cls).__setup__()
        t = cls.__table__()
        cls._sql_constraints = [
            ('date_asset_uniq',
                Unique(t, t.date, t.asset),
                'investment.msg_unique_rate_date'),
            ('check_rate',
                Check(t, t.rate >= 0),
                'currency.msg_rate_positive'),
            ]
        cls._order.insert(0, ('date', 'DESC'))

    @classmethod
    def default_date(cls):
        """ today
        """
        IrDate = Pool().get('ir.date')
        return IrDate.today()

    @classmethod
    def get_rate_data(cls, rates, names):
        """ speed up: get values for rate
        """
        pool = Pool()
        Asset = pool.get('investment.asset')
        tab_asset = Asset.__table__()
        tab_rate = cls.__table__()
        cursor = Transaction().connection.cursor()

        query = tab_asset.join(tab_rate,
                condition=tab_asset.id==tab_rate.asset,
            ).select(
                tab_rate.id,
                tab_asset.uom,
                tab_asset.currency,
                tab_asset.currency_digits,
                where=tab_rate.id.in_([x.id for x in rates]),
            )
        cursor.execute(*query)
        records = cursor.fetchall()

        result = {x:{y.id: None for y in rates} for x in names}
        for record in records:
            r1 = {
                'symbol': '%',
                'uom': record[1],
                'currency': record[2],
                'asset_digits': record[3],
                }

            for n in names:
                result[n][record[0]] = r1[n]
        return result

# Rate