您好我检查了有关我的答案的所有问题，但没有找到解决方案。今天我更改了我的CustomUser模型然后停止工作。我想，我失败了一件事，当django向我询问有关datefield的默认值时，我添加＆＃34;＆＃34; （空字符串），但我不确定。
我尝试删除所有数据库表并再次迁移，尝试删除所有迁移但仍然无法工作
我的模特：
class UserManager(BaseUserManager):
def create_user(self, username, email, password=None):
if not email:
raise ValueError('You must set email ')
if not username:
raise ValueError('User must have username')
user = self.model( username=username,
email=self.normalize_email(email),
)
user.set_password(password)
user.save(using=self._db)
return user
def create_superuser(self, username, email, password):
user = self.create_user(username=username, email=email, password=password)
user.is_admin = True
user.is_superuser = True
user.save(using=self._db)
return user
class CustomUser(AbstractBaseUser, PermissionsMixin):
alphanumeric = RegexValidator(r'^[0-9a-zA-Z]*$', message='Only alphanumeric characters are allowed.')
username = models.CharField(unique=True, max_length=30, validators= [alphanumeric])
email = models.EmailField(
'Email',
max_length=255,
unique=True,
db_index=True
)
avatar = models.ImageField(
'Avatar',
blank=True,
upload_to='user/avatar',
default='user/default.jpg'
)
firstname = models.CharField(
'First name',
max_length=40,
blank=True,
)
lastname = models.CharField(
'Last name',
max_length=40,
blank=True,
)
date_of_birth = models.DateField(
'Date of birth',
null=True,
blank=True,
)
register_date = models.DateField(
'Register date',
auto_now_add=True,
null=True,
blank=True,
)
is_active = models.BooleanField(
'Active',
default=True
)
is_admin = models.BooleanField(
'Superuser',
default=False
)
def age(self):
x = date.today()
if self.date_of_birth.year is None:
return ''
else:
return x.year - self.date_of_birth.year
@property
def is_staff(self):
return self.is_admin
def get_short_name(self):
return self.email
def __str__(self):
return self.email
def has_perm(self, perm, obj=None):
return True
def has_module_perms(self, app_label):
return True
USERNAME_FIELD = 'email'
REQUIRED_FIELDS = ['username']
objects = UserManager()
class Meta:
verbose_name = 'User'
verbose_name_plural = 'Users'
我的服务器日志：
正在运行迁移：
Rendering model states... DONE
Applying admin.0001_initial... OK
Applying sessions.0001_initial... OK
Applying users.0008_auto_20151104_1042...Traceback (most recent call last):
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/core/management/__init__.py", line 338, in execute_from_command_line
utility.execute()
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/core/management/__init__.py", line 330, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/core/management/base.py", line 393, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/core/management/base.py", line 444, in execute
output = self.handle(*args, **options)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/core/management/commands/migrate.py", line 222, in handle
executor.migrate(targets, plan, fake=fake, fake_initial=fake_initial)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/migrations/executor.py", line 110, in migrate
self.apply_migration(states[migration], migration, fake=fake, fake_initial=fake_initial)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/migrations/executor.py", line 148, in apply_migration
state = migration.apply(state, schema_editor)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/migrations/migration.py", line 115, in apply
operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/migrations/operations/fields.py", line 201, in database_forwards
schema_editor.alter_field(from_model, from_field, to_field)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/backends/base/schema.py", line 484, in alter_field
old_db_params, new_db_params, strict)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/backends/base/schema.py", line 567, in _alter_field
new_default = self.effective_default(new_field)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/backends/base/schema.py", line 211, in effective_default
default = field.get_db_prep_save(default, self.connection)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/models/fields/__init__.py", line 710, in get_db_prep_save
prepared=False)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/models/fields/__init__.py", line 1322, in get_db_prep_value
value = self.get_prep_value(value)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/models/fields/__init__.py", line 1317, in get_prep_value
return self.to_python(value)
File "/home/ivan/diabetes_django/venv/lib/python3.4/site-packages/django/db/models/fields/__init__.py", line 1287, in to_python
params={'value': value},
django.core.exceptions.ValidationError: ["'' value has an invalid date format. It must be in YYYY-MM-DD format."]
答案 0 :(得分：1)
django.core.exceptions.ValidationError: ["'' value has an invalid date format. It must be in YYYY-MM-DD format."]
如错误消息所示，空字符串是日期的无效值。您可以提供所需格式的字符串，例如"2015-11-04"，或使用python＆＃39; s date，例如date.today()。
但是，我有点担心迁移中的迁移0008发生了这种变化。更改为现有项目中的自定义用户非常棘手（请参阅warning in the docs）。如果删除所有用户迁移并重新创建它们，那么它应该从头开始创建模型，而不是要求默认日期。