manyi/apilib/utils_json.py

# -*- coding: utf-8 -*-
# !/usr/bin/env python
import json

from bson import ObjectId, Decimal128
from django.core.serializers.json import DjangoJSONEncoder
from django.http import HttpResponse

from apilib.monetary import RMB, VirtualCoin, Ratio, Percent
from apilib.quantity import Quantity


from apilib.systypes import StrEnum


class DescriptiveJSONEncoder(DjangoJSONEncoder):
    def default(self, o):
        import datetime

        if isinstance(o, ObjectId):
            return str(o)
        elif isinstance(o, Decimal128):
            return str(o)
        elif isinstance(o, (RMB, VirtualCoin, Ratio, Percent)):
            return str(o)
        elif isinstance(o, Quantity):
            return str(o)
        elif isinstance(o, datetime.datetime):
            return o.strftime('%Y-%m-%d %H:%M:%S')
        return super(DescriptiveJSONEncoder, self).default(o)


class CustomizedType(StrEnum):
    ObjectId = 'ObjectId'
    Decimal128 = 'Decimal128'
    RMB = 'RMB'
    VirtualCoin = 'VirtualCoin'
    Ratio = 'Ratio'
    Percent = 'Percent'
    Quantity = 'Quantity'
    datetime = 'datetime'


class CustomizedTypeJSONEncoder(DjangoJSONEncoder):
    def default(self, o):
        import datetime

        if isinstance(o, ObjectId):
            return {'_spec_type': CustomizedType.ObjectId, 'val': str(o)}
        elif isinstance(o, Decimal128):
            return {'_spec_type': CustomizedType.Decimal128, 'val': str(o)}
        elif isinstance(o, RMB):
            return {'_spec_type': CustomizedType.RMB, 'val': str(o)}
        elif isinstance(o, VirtualCoin):
            return {'_spec_type': CustomizedType.VirtualCoin, 'val': str(o)}
        elif isinstance(o, Ratio):
            return {'_spec_type': CustomizedType.Ratio, 'val': str(o)}
        elif isinstance(o, Percent):
            return {'_spec_type': CustomizedType.Percent, 'val': str(o)}
        elif isinstance(o, Quantity):
            return {'_spec_type': CustomizedType.Quantity, 'val': str(o)}
        elif isinstance(o, datetime.datetime):
            return {'_spec_type': CustomizedType.datetime, 'val': o.strftime('%Y-%m-%d %H:%M:%S')}

        return super(CustomizedTypeJSONEncoder, self).default(o)


def object_hook(obj):
    _spec_type = obj.get('_spec_type')
    if not _spec_type:
        return obj

    if _spec_type == CustomizedType.ObjectId:
        return ObjectId(obj.get('val'))

    if _spec_type == CustomizedType.RMB:
        return RMB(obj.get('val'))

    elif _spec_type == CustomizedType.VirtualCoin:
        return VirtualCoin(obj.get('val'))

    elif _spec_type == CustomizedType.Ratio:
        return Ratio(obj.get('val'))

    elif _spec_type == CustomizedType.Percent:
        return Percent(obj.get('val'))

    elif _spec_type == CustomizedType.Quantity:
        return Quantity(obj.get('val'))

    elif _spec_type == CustomizedType.datetime:
        import datetime
        return datetime.datetime.strptime(obj.get('val'), '%Y-%m-%d %H:%M:%S')

    elif _spec_type == CustomizedType.Decimal128:
        return Decimal128(str(obj.get('val')))

    raise Exception('Unknown {}'.format(_spec_type))


def json_dumps(data, sort_keys = False, serialize_type = False):
    if not serialize_type:
        return json.dumps(data, sort_keys = sort_keys, cls = DescriptiveJSONEncoder)
    else:
        return json.dumps(data, sort_keys = sort_keys, cls = CustomizedTypeJSONEncoder)


def json_loads(data):
    return json.loads(data, object_hook = object_hook)


class JsonResponse(HttpResponse):
    def __init__(self, data, safe = True, ordered = False, **kwargs):
        if safe and not isinstance(data, dict):
            raise TypeError('In order to allow non-dict objects to be '
                            'serialized set the safe parameter to False')
        kwargs.setdefault('content_type', 'application/json')
        data = json_dumps(data, sort_keys = ordered)
        super(JsonResponse, self).__init__(content = data, **kwargs)

    def json(self):
        return json.loads(self.content)