我有一个模型注释，创建时可能会也可能不会创建新用户。因此，我的API在创建新评论时需要密码字段。这是我的评论模型：
class Comment(models.Model):
commenter = models.ManyToManyField(Commenter)
email = models.EmailField(max_length=100)
author = models.CharField(max_length=100)
url = models.URLField(max_length=200)
content = models.TextField(blank=True, null=True)
ip = models.IPAddressField(max_length=45)
date = models.DateTimeField(default=datetime.now)
post_title = models.CharField(max_length=200)
post_url = models.URLField(max_length=200)
rating = models.IntegerField(max_length=10, default=0)
以下是我的API视图：
class CommentNewView(CreateAPIView):
model = Comment
serializer_class = CommentCreateSerializer
这是我的序列化器：
class CommentCreateSerializer(serializers.ModelSerializer):
commenter_pw = serializers.CharField(max_length=32, required=False)
class Meta:
model = Comment
fields = ('email', 'author', 'url', 'content', 'ip', 'post_title', 'post_url', 'commenter_pw')
以下是我遇到的错误：
Environment:
Request Method: POST
Request URL: http://127.0.0.1:8000/api/comment/create/
Django Version: 1.5.2
Python Version: 2.7.2
Installed Applications:
('commentflow.apps.dashboard',
'commentflow.apps.commenter',
'commentflow.apps.comment',
'rest_framework',
'rest_framework.authtoken',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.sites',
'django.contrib.messages',
'django.contrib.staticfiles',
'django.contrib.admin',
'django.contrib.admindocs')
Installed Middleware:
('django.middleware.common.CommonMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.locale.LocaleMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware')
Traceback:
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response
115. response = callback(request, *callback_args, **callback_kwargs)
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/django/views/generic/base.py" in view
68. return self.dispatch(request, *args, **kwargs)
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/django/views/decorators/csrf.py" in wrapped_view
77. return view_func(*args, **kwargs)
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/rest_framework/views.py" in dispatch
327. response = self.handle_exception(exc)
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/rest_framework/views.py" in dispatch
324. response = handler(request, *args, **kwargs)
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/rest_framework/generics.py" in post
372. return self.create(request, *args, **kwargs)
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/rest_framework/mixins.py" in create
50. if serializer.is_valid():
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/rest_framework/serializers.py" in is_valid
479. return not self.errors
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/rest_framework/serializers.py" in errors
471. ret = self.from_native(data, files)
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/rest_framework/serializers.py" in from_native
867. instance = super(ModelSerializer, self).from_native(data, files)
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/rest_framework/serializers.py" in from_native
324. return self.restore_object(attrs, instance=getattr(self, 'object', None))
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/rest_framework/serializers.py" in restore_object
852. instance = self.opts.model(**attrs)
File "/Users/tlovett1/.virtualenvs/commentflow/lib/python2.7/site-packages/django/db/models/base.py" in __init__
415. raise TypeError("'%s' is an invalid keyword argument for this function" % list(kwargs)[0])
Exception Type: TypeError at /api/comment/create/
Exception Value: 'commenter_pw' is an invalid keyword argument for this function
答案 0 :(得分：10)
如果有人好奇，解决方案是覆盖restore_object方法并在实例化后将额外的实例变量添加到注释对象中：
def restore_object(self, attrs, instance=None):
if instance is not None:
instance.email = attrs.get('email', instance.email)
instance.author = attrs.get('author', instance.author)
instance.url = attrs.get('url', instance.url)
instance.content = attrs.get('content', instance.content)
instance.ip = attrs.get('ip', instance.ip)
instance.post_title = attrs.get('post_title', instance.post_title)
instance.post_url = attrs.get('post_url', instance.post_url)
return instance
commenter_pw = attrs.get('commenter_pw')
del attrs['commenter_pw']
comment = Comment(**attrs)
comment.commenter_password = commenter_pw
return comment
答案 1 :(得分：6)
以前的答案在DRF3.0上不起作用，现在不推荐使用restore_object（）方法。
我使用的解决方案很糟糕，但我找不到更好的解决方案。 我在模型上为这个字段放了一个虚拟的getter / setter，这允许在模型上使用这个字段。
请记住在串行器定义上将字段设置为write_only。
class Comment(models.Model):
@property
def commenter_pw():
return None
@commenter_pw.setter
def commenter_pw(self, value):
pass
class CommentCreateSerializer(serializers.ModelSerializer):
commenter_pw = serializers.CharField(max_length=32, write_only=True, required=False)
class Meta:
model = Comment
fields = ('email', 'author', 'url', 'content', 'ip', 'post_title', 'post_url', 'commenter_pw')
答案 2 :(得分：2)
感谢您自己的回答，它给了我很多帮助:)。
但我认为这有点更通用，因为我仍然想在超级串行器类上调用该方法
def restore_object(self, attrs, instance=None):
'''
we have to ensure that the temporary_password is attached to the model
even though it is no field
'''
commenter_pw = attrs.pop('comment_pw', None)
obj = super(
CommentCreateSerializer, self
).restore_object(attrs, instance=instance)
if commenter_pw:
obj.commenter_pw = commenter_pw
return obj
答案 3 :(得分：0)
您可以做的是覆盖pre_save或create功能并从发送的数据字段中取出commenter_pw（不确定，但您可以将其取出）从request.POST开始，或者在序列化之后），所以框架不应该出错。
另外，如果你有其他逻辑，你可以在保存它之前在那里实现它（例如用于检查是否必须创建用户或者是什么的那个）。