loads允许字典中有重复的键，覆盖第一个值

Question

>>> raw_post_data = request.raw_post_data
>>> print raw_post_data
{"group":{"groupId":"2", "groupName":"GroupName"}, "members":{"1":{"firstName":"fName","lastName":"LName","address":"address"},"1": {"firstName":"f_Name","lastName":"L_Name","address":"_address"}}}
>>> create_request = json.loads(raw_post_data)
>>> print create_request
{u'group': {u'groupName': u'GroupName', u'groupId': u'2'}, u'members': {u'1': {u'lastName': u'L_Name', u'firstName': u'f_Name', u'address': u'_address'}}}

如您所见，当我使用json.dumps()时，键为“1”的成员将被覆盖

有没有办法在python中将其捕获为异常，即在来自客户端的请求中发现重复的密钥？

Answer 1

或者，如果您想捕获所有重复的键（每个级别），可以使用collections.Counter

from collections import Counter

class KeyWatcher(dict):

    def __init__(self, *args):
        duplicates = [d for d,i in Counter([pair[0] for pair in args[0]]).items() if i > 0]
        if duplicates:
            raise KeyError("Can't add duplicate keys {} to a json message".format(duplicates))
        self.update(*args[0])

json.loads(raw_post_data, object_pairs_hook=KeyWatcher)