A son manipulator for decimal.Decimal

DecimalTransform.py

from decimal import Decimal
from pymongo.son_manipulator import SONManipulator

class DecimalTransform(SONManipulator):
    def transform_incoming(self, son, collection):
        for (key, value) in son.items():
            if isinstance(value, Decimal):
                son[key] = {'_type' : 'decimal', 'value' : unicode(value)}
            elif isinstance(value, dict):
                son[key] = self.transform_incoming(value, collection)
        return son

    def transform_outgoing(self, son, collection):
        for (key, value) in son.items():
            if isinstance(value, dict):
                if "_type" in value and value["_type"] == "decimal":
                   son[key] = Decimal(value['value'])
                else: 
                   son[key] = self.transform_outgoing(value, collection)
        return son