问题描述
我正在尝试使用Django中的json.dumps()
将一个对象编码为json,但是当我传入一个python对象时,它会引发这个错误。
TypeError: <OrgInvite: OrgInvite object> is not JSON serializable
我的假设是,即使JSON只能编码某些数据类型,这些数据类型之一也是对象。我读到了关于Stack Overflow的另一个问题,一个解决这个问题的好方法是使用.__dict__
从对象创建一个字典。我尝试了这个方法,结果发现我的新字典_STATE中的一个键是不可序列化的。我不确定这个_STATE键是从哪里来的,我想知道有没有一种方法可以将我的对象转换为字典,而不需要额外的字段,这样我就可以将它编码成JSON?
型号:
class OrgInvite(models.Model):
token = models.CharField(max_length=16, unique=True, null=False)
account_id = models.ForeignKey(Account, on_delete=models.CASCADE, null=False)
org_id = models.ForeignKey(Org, on_delete=models.CASCADE, null=False)
used = models.BooleanField(default=False)
is_admin = models.BooleanField(default=False)
name = models.CharField(max_length=70)
email = models.CharField(max_length=255)
查看:
def get_invite(token):
if not token:
raise Exception("Invitation token is not specified")
invitation = OrgInvite.objects.get(token=token)
if not invitation:
raise Exception("Invitation token is invalid.")
return invitation
def invite_accept_redirect(token):
# """ -Redirects to the accept invite frontend view with pre-fetched data. """
try:
invite = get_invite(token)
if not invite:
raise Exception("Invitation token is invalid")
if invite.used:
invite = {'used': True}
except:
invite = {'invalid': True}
raise Exception("Resource not found.")
base = "home/accept"
url = '{}/{}?data={}'.format(base, token, urllib.quote_plus(json.dumps(invite.__dict__)))
return redirect(url)
控制台:
>>> oi = OrgInvite.objects.get(token=100)
>>> oi
<OrgInvite: OrgInvite object>
>>> oix = oi.__dict__
>>> oix
{'used': False, 'name': u'', '_state': <django.db.models.base.ModelState object at 0x10377a610>, 'email': u'', 'token': u'100', 'org_id_id': 101, 'account_id_id': 301, 'is_admin': False, 'id': 1}
>>> json.dumps(oix)
Traceback (most recent call last):
File "<console>", line 1, in <module>
File "/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/__init__.py", line 244, in dumps
return _default_encoder.encode(obj)
File "/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/encoder.py", line 207, in encode
chunks = self.iterencode(o, _one_shot=True)
File "/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/encoder.py", line 270, in iterencode
return _iterencode(o, 0)
File "/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/encoder.py", line 184, in default
raise TypeError(repr(o) + " is not JSON serializable")
TypeError: <django.db.models.base.ModelState object at 0x10377a610> is not JSON serializable
推荐答案
__dict__
给出了实例的所有属性,但您不想要这些额外的包袱--出于序列化的目的,您只对字段感兴趣。
您的模型不包含任何特殊内容,因此内置的helper函数model_to_dict
应该足以满足您的需要:
import json
from django.forms.models import model_to_dict
oi = OrgInvite.objects.get(token=100)
oi_dict = model_to_dict(oi)
oi_serialized = json.dumps(oi_dict)
您的示例很简单,只包含CharField
、BooleanField
和ForeignKey
,我们可以简单地将它们全部转储到json
。
对于更复杂的模型,您可以考虑编写自己的serializer。在这种情况下,我建议使用流行的django-rest-framework,它可以为您完成所有工作。
from rest_framework import serializers
class OrgInviteSerializer(serializers.ModelSerializer):
class Meta:
model = OrgInvite
fields = '__all__'