如何将用户模型传递到表单字段（django）？

Question

基本上，我需要使用用户的密码哈希通过自定义模型字段来加密一些数据。查看我在这里使用的代码片段：Django 加密。

我尝试了这个：

class MyClass(models.Model):
    owner = models.ForeignKey(User)
    product_id = EncryptedCharField(max_length=255, user_field=owner)

.................................................................................

    def formfield(self, **kwargs):
        defaults = {'max_length': self.max_length, 'user_field': self.user_field}
        defaults.update(kwargs)
        return super(EncryptedCharField, self).formfield(**defaults))

但是当我尝试使用 user_field 时，我得到一个外键实例（当然！）：

user_field = kwargs.get('user_field')
cipher = user_field.password[:32]

感谢任何帮助！

Answer 1

也许是这样的 - 重写 save() 方法，您可以在其中调用加密方法。

为了解密，您可以使用 signal post_init ，因此每次实例化模型时从数据库中，product_id 字段会自动解密，

class MyClass(models.Model):
    user_field = models.ForeignKey(User)
    product_id = EncryptedCharField()
    ...other fields...

    def save(self):
        self.product_id._encrypt(product_id, self.user_field)
        super(MyClass,self).save()

    def decrypt(self):
        if self.product_id != None:
            user = self.user_field
            self.product_id._decrypt(user=user)

def post_init_handler(sender_class, model_instance):
    if isinstance(model_instance, MyClass):
        model_instance.decrypt()

from django.core.signals import post_init
post_init_connect.connect(post_init_handler)


obj = MyClass(user_field=request.user) 
#post_init will be fired but your decrypt method will have
#nothing to decrypt, so it won't garble your input
#you'll either have to remember not to pass value of crypted fields 
#with the constructor, or enforce it with either pre_init method 
#or carefully overriding __init__() method - 
#which is not recommended officially

#decrypt will do real decryption work when you load object form the database

obj.product_id = 'blah'
obj.save() #field will be encrypted

也许有一种更优雅的“pythonic”方式可以做到这一点