AttribueError 与 Django 和 mysql 连接器 python

Question

我在我的 django 数据库中使用 SQLite，我想在我的 Synology NAS 上使用 MariaDb。

我在 Python 3.9.0+ 和 MariaDB 10.3.24 上使用 Django 3.2

我使用 pip 包 mysql-connector-python==8.0.23 作为 mysql 连接器。

DATABASES = {
    'default': {
        'ENGINE': 'mysql.connector.django',
        'NAME': 'energyHomeWeb_django',
        'USER': 'energyHomeWeb',
        'PASSWORD': 'password',
        'HOST': '192.168.1.123',
        'PORT': '3307',
        'OPTIONS': {
            'autocommit': True,
        },
    }
}

当我想启动或迁移我的服务器时，我遇到了这个错误：

      Exception in thread django-main-thread:
Traceback (most recent call last):
  File "/usr/lib/python3.9/threading.py", line 950, in _bootstrap_inner
    self.run()
  File "/usr/lib/python3.9/threading.py", line 888, in run
    self._target(*self._args, **self._kwargs)
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/utils/autoreload.py", line 64, in wrapper
    fn(*args, **kwargs)
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/core/management/commands/runserver.py", line 121, in inner_run
    self.check_migrations()
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/core/management/base.py", line 486, in check_migrations
    executor = MigrationExecutor(connections[DEFAULT_DB_ALIAS])
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/migrations/executor.py", line 18, in __init__
    self.loader = MigrationLoader(self.connection)
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/migrations/loader.py", line 53, in __init__
    self.build_graph()
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/migrations/loader.py", line 220, in build_graph
    self.applied_migrations = recorder.applied_migrations()
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/migrations/recorder.py", line 77, in applied_migrations
    if self.has_table():
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/migrations/recorder.py", line 55, in has_table
    with self.connection.cursor() as cursor:
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/utils/asyncio.py", line 26, in inner
    return func(*args, **kwargs)
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/backends/base/base.py", line 259, in cursor
    return self._cursor()
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/backends/base/base.py", line 235, in _cursor
    self.ensure_connection()
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/utils/asyncio.py", line 26, in inner
    return func(*args, **kwargs)
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/backends/base/base.py", line 219, in ensure_connection
    self.connect()
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/utils/asyncio.py", line 26, in inner
    return func(*args, **kwargs)
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/backends/base/base.py", line 202, in connect
    self.init_connection_state()
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/mysql/connector/django/base.py", line 341, in init_connection_state
    if self.features.is_sql_auto_is_null_enabled:
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/utils/functional.py", line 48, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/django/db/backends/mysql/features.py", line 150, in is_sql_auto_is_null_enabled
    return self.connection.mysql_server_data['sql_auto_is_null']
  File "/home/iomys/.virtualenvs/energyHomeWeb/lib/python3.9/site-packages/mysql/connector/django/base.py", line 290, in __getattr__
    raise AttributeError
AttributeError

我该如何解决这个问题？

PS：我不使用 mysqlclient，因为它不能在我的 virtualenv 上工作，而且我不知道如何让它工作。

Answer 1

引擎不正确

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql', 
        'NAME': 'energyHomeWeb_django',
        'USER': 'energyHomeWeb',
        'PASSWORD': 'password',
        'HOST': '192.168.1.123',
        'PORT': '3307',
        'OPTIONS': {
            'autocommit': True,
        },
    }
}

Answer 2

最后，我将我的 Python 版本更改为 Python 3.8，mysqlclient 可以在 python3.8 上正常工作。

所以我使用了它，它现在可以工作了，但是有了这个配置：

DATABASES = {
'default': {
    'ENGINE': 'django.db.backends.mysql', 
    'NAME': 'energyHomeWeb_django',
    'USER': 'energyHomeWeb',
    'PASSWORD': 'password',
    'HOST': '192.168.1.123',
    'PORT': '3307',
    'OPTIONS': {
        'autocommit': True,
        },
    }
}

Answer 3

我遇到了同样的错误。

pip freeze 的输出

asgiref==3.3.4
asttokens==2.0.4
colorama==0.4.4
Django==3.2
dnspython==1.16.0
executing==0.6.0
icecream==2.1.0
mysql-connector-python==8.0.23
protobuf==3.15.8
Pygments==2.8.1
pytz==2021.1
six==1.15.0
sqlparse==0.4.1

在浏览了源代码后，我通过对文件venv/lib/python3.8/site-packages/mysql/connector/django/base.py做一点小改动解决了这个问题（假设您使用的是 venv 并将您的虚拟环境命名为 venv)

    def __getattr__(self, attr):
        if attr.startswith("mysql_is"):
            return False
        raise AttributeError
    
    # copied from venv/lib/python3.8/site-packages/django/db/backends/mysql/base.py
    # and modified to use with self.cursor() as cursor: (see init_connection_state() )
    @cached_property
    def mysql_server_data(self):
        with self.cursor() as cursor:
            # Select some server variables and test if the time zone
            # definitions are installed. CONVERT_TZ returns NULL if 'UTC'
            # timezone isn't loaded into the mysql.time_zone table.
            cursor.execute("""
                SELECT VERSION(),
                       @@sql_mode,
                       @@default_storage_engine,
                       @@sql_auto_is_null,
                       @@lower_case_table_names,
                       CONVERT_TZ('2001-01-01 01:00:00', 'UTC', 'UTC') IS NOT NULL
            """)
            row = cursor.fetchone()
        return {
            'version': row[0],
            'sql_mode': row[1],
            'default_storage_engine': row[2],
            'sql_auto_is_null': bool(row[3]),
            'lower_case_table_names': bool(row[4]),
            'has_zoneinfo_database': bool(row[5]),
        }

升级到 8.0.24 版本对我来说不是一个选项，因为它会产生另一个错误。