python - 自定义用户模型的问题

Question

我半年前只完成了一个教程，这是我从那时起的第一个代码，所以请原谅我知识的缺乏。我试图通过在 Google 中搜索信息来使此代码正常工作，但我陷入了困境。

from django_uuid_pk.fields import UUIDField
from django.db import models
from django.utils import timezone
from django.utils.http import urlquote
from django.utils.translation import ugettext_lazy as _
from django.core.mail import send_mail
from django.contrib.auth.models import AbstractBaseUser, PermissionsMixin
from django.contrib.auth.models import BaseUserManager
from django.core.exceptions import ObjectDoesNotExist


class Avatar(models.Model):
    first_name = models.CharField(_('first name'), max_length=30)
    last_name = models.CharField(_('last name'), max_length=30)
    uuid = UUIDField(unique = True, primary_key = True)
    class Meta:
        unique_together = ('first_name', 'last_name',)

class CustomUserManager(BaseUserManager):

    def _create_user(self, first_name, last_name, uuid, password, email,
                    is_staff, is_superuser, **extra_fields):
        now = timezone.now()
        email = self.normalize_email(email)
        try:
            avatar = Avatar.objects.get(pk=uuid)
        except ObjectDoesNotExist:
            avatar = Avatar.objects.create(uuid=uuid, first_name=first_name, last_name=last_name)

        user = self.model(avatar=avatar, email=email, is_staff=is_staff, is_superuser=is_superuser, **extra_fields)
        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_user(self, first_name, last_name, uuid, password=None, email=None, **extra_fields):
        return self._create_user(first_name, last_name, uuid, password, email, False, False,
                                 **extra_fields)

    def create_superuser(self, first_name, last_name, uuid, password=None, email=None, **extra_fields):
        return self._create_user(first_name, last_name, uuid, password, email, True, True,
                                 **extra_fields)

class CustomUser(AbstractBaseUser, PermissionsMixin):
    avatar = models.ForeignKey('Avatar', unique=True)
    email = models.EmailField(_('email address'), max_length=254, blank=True)
    is_staff = models.BooleanField(_('staff status'), default=False)
    is_active = models.BooleanField(_('active'), default=True)
    date_joined = models.DateTimeField(_('date joined'), default=timezone.now)

    objects = CustomUserManager()

    USERNAME_FIELD = 'avatar'

    class Meta:
        verbose_name = _('user')
        verbose_name_plural = _('users')

        def get_short_name(self):
            return self.avatar.first_name

当我尝试通过命令在 shell 中创建用户时:

CustomUser.objects.create_user('Philip', 'Philips', 'f86cff00-2076-11e4-8c21-0800200c9a66', '123456')

我收到错误:

IntegrityError: UNIQUE constraint failed: myproject_accounts_customuser.avatar_id

Answer 1

您在 CustomUser 模型中的 avatar 字段上有 unique=True。但在您的自定义管理器中您有以下代码:

    try:
        avatar = Avatar.objects.get(pk=uuid)
    except ObjectDoesNotExist:
        avatar = Avatar.objects.create(uuid=uuid, first_name=first_name, last_name=last_name)

如果具有该 uuid 的头像存在，您将获得一个头像对象，django 将尝试使用该对象创建用户。但由于头像是唯一的，如果数据库中存在具有该头像的用户，您将收到 IntegrityError。如果头像对象已经存在，如果您需要独特的行为，您应该在这个地方引发自定义异常。如果没有，请删除 unique=True。