I have a Decimal('3.9')
as part of an object, and wish to encode this to a JSON string which should look like {'x': 3.9}
. I don't care about precision on the client side, so a float is fine.
Is there a good way to serialize this? JSONDecoder doesn't accept Decimal objects, and converting to a float beforehand yields {'x': 3.8999999999999999}
which is wrong, and will be a big waste of bandwidth.
Simplejson 2.1 and higher has native support for Decimal type:
>>> json.dumps(Decimal('3.9'), use_decimal=True)
'3.9'
Note that use_decimal
is True
by default:
def dumps(obj, skipkeys=False, ensure_ascii=True, check_circular=True,
allow_nan=True, cls=None, indent=None, separators=None,
encoding='utf-8', default=None, use_decimal=True,
namedtuple_as_object=True, tuple_as_array=True,
bigint_as_string=False, sort_keys=False, item_sort_key=None,
for_json=False, ignore_nan=False, **kw):
So:
>>> json.dumps(Decimal('3.9'))
'3.9'
Hopefully, this feature will be included in standard library.