UserProfile 模型不保存 ForeignKeys

Question

我遵循了以下指南：http://www.turnkeylinux.org/blog/django-profile，它运行良好，除了我似乎无法将 ForeignKey 保存到用户配置文件中。

模型

PCBuild 模型

from django.contrib.auth.models import User
from django.db import models

class PCBuild(models.Model):
    name = models.CharField(max_length=50)
    owner = models.ForeignKey(User)

用户档案模型

import datetime
import md5

from apps.pcbuilder.models import PCBuild
from django.contrib.auth.models import User
from django.db import models

class UserProfile(models.Model):   
    user = models.OneToOneField(User)
    email_hash = models.CharField(max_length=200) #MD5 hash of e-mail

    current_build = models.ForeignKey(PCBuild, 
        related_name='current_build', null=True, blank=True)

    def __unicode__(self):
        return self.user.email 


User.profile = property(lambda u: UserProfile.objects.get_or_create(
                            user=u, 
                            email_hash=md5.new(u.email).hexdigest())[0])

问题示例

>>> from django.contrib.auth.models import User
>>> from apps.pcbuilder.models import PCBuild
>>> from django.shortcuts import get_object_or_404

>>> user = get_object_or_404(User, pk=2)
>>> user
    <User: Trevor>

>>> pcbuild = get_object_or_404(PCBuild, pk=11)
>>> pcbuild
    <PCBuild: StackOverflowBuild>

>>> pcbuild.owner
    <User: Trevor>

>>> user.profile.email_hash
    u'd41d8cd98f00b204e9800998ecf8427e'

>>> user.profile.current_build = pcbuild
>>> user.profile.save()
>>> user.profile.current_build
    # nothing is stored/outputted - this is the problem!

我是 Django 的新手，尽管到目前为止 Google 一直很有帮助，但几个小时后我还没有征服它。如果需要有关此问题的更多信息，我很乐意提供！

谢谢。

编辑：

我发现可能有用的东西（但没有解决我的特定问题）：

• https://docs.djangoproject.com/en/dev/topics/db/queries/#saving-foreignkey-and-manytomanyfield-fields

• http://sam.odio.com/blog/2008/05/extending-user-model-profiles-in-django.php

Answer 1

您将在使用该属性的情况下遇到神秘的错误。由于UserProfile 到User 的关系是OneToOneField，您可以通过执行user.userprofile 从实例访问配置文件实例。如果您想更改名称，可以更新OneToOneField 的related_name 属性。

在创建用户时使用信号自动创建配置文件，如下所示：

from django.contrib.auth.models import User
from django.db.models.signals import post_save

def create_profile(sender, **kwargs):
    """Create a UserProfile instance when a User is created."""
    u = kwargs['instance']
    if kwargs['created']:
        UserProfile.objects.get_or_create(
                        user=u, 
                        email_hash=md5.new(u.email).hexdigest())

post_save.connect(create_profile, sender=User)

Answer 2

我想通了 - 但我仍然愿意接受其他答案，稍后再回来查看。我很确定这与我用来获取配置文件的 lambda 函数有关。我是如何在 python shell 中进行的：

>>> from django.contrib.auth.models import User
>>> from apps.pcbuilder.models import PCBuild
>>> from django.shortcuts import get_object_or_404
>>> user = get_object_or_404(User, pk=2)
>>> user
    <User: Trevor>

>>> pcbuild = get_object_or_404(PCBuild, pk=11)
>>> pcbuild
    <PCBuild: StackOverflowBuild>

>>> user.profile.current_build
    # nothing (which is expected as there is nothing 
    # yet in the current_build of this user profile)


# NOTE: I'm creating a new "profile" variable that holds the user profile.

>>> profile = user.profile
>>> profile
    <UserProfile: Trevor>

>>> profile.current_build
    # nothing (which is expected as there is nothing 
    # yet in the current_build of this user profile)

>>> profile.current_build = pcbuild
>>> profile.save()

>>> user.profile.current_build
    <PCBuild: StackOverflowBuild>

    # As you can see, it worked!

我基本上必须将 user.profile 分配给它自己的变量（示例中为 profile），然后在修改变量后保存它而不是用户对象.

看起来有点尴尬，但确实有效。