Python 尽管单元测试功能正常，Authtoken迁移仍不工作

我正在为我们的django项目添加内容。一切进展顺利，我为令牌身份验证添加了迁移和单元测试：

# Migration
from django.db import migrations


def create_missing_tokens(apps, schema_editor):
    """
    Tokens were added in 0002_auto_20160226_1747, we thus need to populate
    the tokens table for existing users
    """
    Token = apps.get_model('authtoken', 'Token')
    User = apps.get_model('accounts', 'CustomUser')
    for user in User.objects.all():
        Token.objects.get_or_create(user=user)


class Migration(migrations.Migration):

    dependencies = [
        # depends on authtoken migration
        ('accounts', '0003_subscription_max_updates_per_day'),
        ('authtoken', '0002_auto_20160226_1747'), # latest migration in the authtoken package
    ]
    operations = [
        migrations.RunPython(create_missing_tokens, reverse_code=migrations.RunPython.noop),
    ]

这非常有效，但当我实际运行迁移时，我得到了以下信息：

django.db.utils.IntegrityError:重复的键值违反了唯一性 约束“authtoken\u token\u pkey”详细信息：键（Key）=（）已存在 存在

下面是我所说的“实际运行迁移”的一些伪代码：

我无法理解使用

Token.objects.get\u或\u create（user=user）

的迁移如何获得重复的密钥？任何帮助都将不胜感激

  Applying accounts.0004_create_tokens...Traceback (most recent call last):
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 538, in get_or_create
    return self.get(**kwargs), False
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 408, in get
    self.model._meta.object_name
__fake__.DoesNotExist: Token matching query does not exist.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
psycopg2.errors.UniqueViolation: duplicate key value violates unique constraint "authtoken_token_pkey"
DETAIL:  Key (key)=() already exists.


The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "manage.py", line 15, in <module>
    execute_from_command_line(sys.argv)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
    utility.execute()
  File "/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 323, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 364, in execute
    output = self.handle(*args, **options)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 83, in wrapped
    res = handle_func(*args, **kwargs)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/commands/migrate.py", line 234, in handle
    fake_initial=fake_initial,
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 117, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 147, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 245, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/migration.py", line 124, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/operations/special.py", line 190, in database_forwards
    self.code(from_state.apps, schema_editor)
  File "/code/accounts/migrations/0004_create_tokens.py", line 12, in create_missing_tokens
    Token.objects.get_or_create(user=user)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 541, in get_or_create
    return self._create_object_from_params(kwargs, params)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 583, in _create_object_from_params
    raise e
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 575, in _create_object_from_params
    obj = self.create(**params)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 422, in create
    obj.save(force_insert=True, using=self.db)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/base.py", line 741, in save
    force_update=force_update, update_fields=update_fields)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/base.py", line 779, in save_base
    force_update, using, update_fields,
  File "/usr/local/lib/python3.6/site-packages/django/db/models/base.py", line 870, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/base.py", line 908, in _do_insert
    using=using, raw=raw)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 1186, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/sql/compiler.py", line 1335, in execute_sql
    cursor.execute(sql, params)
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 99, in execute
    return super().execute(sql, params)
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 67, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 76, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/usr/local/lib/python3.6/site-packages/django/db/utils.py", line 89, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
django.db.utils.IntegrityError: duplicate key value violates unique constraint "authtoken_token_pkey"
DETAIL:  Key (key)=() already exists.

---

令牌的密钥通常由其
save（）
方法生成。当您手动生成令牌时，这很好，但在迁移中，您通过
应用程序引用模型。get_model（）

所以现在的情况是，令牌是用空键生成的。第一个可以工作，但之后会产生此错误，因为密钥不是唯一的

一个简单的解决方法是将DRF用于生成密钥的代码复制到迁移中。像这样的方法应该会奏效：

for user in User.objects.using(db_alias).all():
    key = binascii.hexlify(os.urandom(20)).decode()
    Token.objects.using(db_alias).get_or_create(user=user, key=key)

你的
CustomUser
类是什么样子的？我猜你的数据库在你设置东西的时候，不知怎么的被占用了。你试过打开shell并检查现有的
令牌
对象吗？@Ben更新了这个问题，谢谢你的关注。我怀疑
username=None
是个问题。但我没有任何结论性的答案。我想我也会这样看：1。AUTH_USER_MODEL='accounts.CustomUser'，2。安装的应用程序安装正确，3。确保
python manage.py drf\u create\u令牌
有效
django.db.utils.IntegrityError: duplicate key value violates unique constraint "authtoken_token_pkey"
DETAIL:  Key (key)=() already exists.

  Applying accounts.0004_create_tokens...Traceback (most recent call last):
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 538, in get_or_create
    return self.get(**kwargs), False
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 408, in get
    self.model._meta.object_name
__fake__.DoesNotExist: Token matching query does not exist.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
psycopg2.errors.UniqueViolation: duplicate key value violates unique constraint "authtoken_token_pkey"
DETAIL:  Key (key)=() already exists.


The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "manage.py", line 15, in <module>
    execute_from_command_line(sys.argv)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
    utility.execute()
  File "/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 323, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 364, in execute
    output = self.handle(*args, **options)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 83, in wrapped
    res = handle_func(*args, **kwargs)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/commands/migrate.py", line 234, in handle
    fake_initial=fake_initial,
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 117, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 147, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 245, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/migration.py", line 124, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/usr/local/lib/python3.6/site-packages/django/db/migrations/operations/special.py", line 190, in database_forwards
    self.code(from_state.apps, schema_editor)
  File "/code/accounts/migrations/0004_create_tokens.py", line 12, in create_missing_tokens
    Token.objects.get_or_create(user=user)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 541, in get_or_create
    return self._create_object_from_params(kwargs, params)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 583, in _create_object_from_params
    raise e
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 575, in _create_object_from_params
    obj = self.create(**params)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 422, in create
    obj.save(force_insert=True, using=self.db)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/base.py", line 741, in save
    force_update=force_update, update_fields=update_fields)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/base.py", line 779, in save_base
    force_update, using, update_fields,
  File "/usr/local/lib/python3.6/site-packages/django/db/models/base.py", line 870, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/base.py", line 908, in _do_insert
    using=using, raw=raw)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/query.py", line 1186, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/usr/local/lib/python3.6/site-packages/django/db/models/sql/compiler.py", line 1335, in execute_sql
    cursor.execute(sql, params)
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 99, in execute
    return super().execute(sql, params)
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 67, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 76, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/usr/local/lib/python3.6/site-packages/django/db/utils.py", line 89, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/usr/local/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
django.db.utils.IntegrityError: duplicate key value violates unique constraint "authtoken_token_pkey"
DETAIL:  Key (key)=() already exists.


class CustomUser(AbstractUser):
    """
    Replace username by email as required and unique.
    """
    is_alphanumeric_or_dash = RegexValidator(r'^[0-9a-zA-Z\-]*$', 'Only alphanumeric and "-" characters are allowed.')

    # Hide username
    username = None

    # Overidde other fields
    email = models.EmailField(_('email address'), unique=True)
    first_name = models.CharField(_('first name'),
                                  max_length=100,
                                  blank=True,
                                  validators=[is_alphanumeric_or_dash])
    last_name = models.CharField(_('last name'),
                                 max_length=100,
                                 blank=True,
                                 validators=[is_alphanumeric_or_dash])

    # /!\ At some point, user should have a default subcription /!\
    subscription = models.ForeignKey(Subscription, on_delete=models.PROTECT, blank=True, null=True)
    # some other fields, but nothing special...
    USERNAME_FIELD = 'email'
    # Override the UserManager with our custom one (for objects creation)
    objects = CustomUserManager()

for user in User.objects.using(db_alias).all():
    key = binascii.hexlify(os.urandom(20)).decode()
    Token.objects.using(db_alias).get_or_create(user=user, key=key)