from sqlalchemy import types
from .. import i18n, ImproperlyConfigured
from ..primitives import Currency
from .scalar_coercible import ScalarCoercible
[docs]class CurrencyType(ScalarCoercible, types.TypeDecorator):
"""
Changes :class:`.Currency` objects to a string representation on the way in
and changes them back to :class:`.Currency` objects on the way out.
In order to use CurrencyType you need to install Babel_ first.
.. _Babel: https://babel.pocoo.org/
::
from sqlalchemy_utils import CurrencyType, Currency
class User(Base):
__tablename__ = 'user'
id = sa.Column(sa.Integer, autoincrement=True)
name = sa.Column(sa.Unicode(255))
currency = sa.Column(CurrencyType)
user = User()
user.currency = Currency('USD')
session.add(user)
session.commit()
user.currency # Currency('USD')
user.currency.name # US Dollar
str(user.currency) # US Dollar
user.currency.symbol # $
CurrencyType is scalar coercible::
user.currency = 'US'
user.currency # Currency('US')
"""
impl = types.String(3)
python_type = Currency
cache_ok = True
def __init__(self, *args, **kwargs):
if i18n.babel is None:
raise ImproperlyConfigured(
"'babel' package is required in order to use CurrencyType."
)
super().__init__(*args, **kwargs)
def process_bind_param(self, value, dialect):
if isinstance(value, Currency):
return value.code
elif isinstance(value, str):
return value
def process_result_value(self, value, dialect):
if value is not None:
return Currency(value)
def _coerce(self, value):
if value is not None and not isinstance(value, Currency):
return Currency(value)
return value