Mac M1 Max下Django集成MySQL执行makemigrations报错求助

我是Django新手，执行python3 manage.py makemigrations时触发报错，核心错误是ImportError：无法加载libmysqlclient.21.dylib库，后续引发NameError: name '_mysql' is not defined。已完成以下操作但未解决：

• 通过pip3 install mysqlclient安装了依赖
• 验证settings.py数据库配置无误
• 尝试创建软链接ln -s /usr/local/mysql-8.0.31-macos12-arm64/lib/libmysqlclient.21.dylib /usr/lib/libmysqlclient.21.dylib

报错栈信息 #

demoproject lamidotijjo$ python3 manage.py makemigrations
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/MySQLdb/__init__.py", line 18, in <module>
    from . import _mysql
ImportError: dlopen(/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/MySQLdb/_mysql.cpython-310-darwin.so, 0x0002): Library not loaded: /opt/homebrew/opt/mysql/lib/libmysqlclient.21.dylib
  Referenced from: <D6AC4B91-4AA0-31A5-AA10-DE3277524713> /Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/MySQLdb/_mysql.cpython-310-darwin.so
  Reason: tried: '/opt/homebrew/opt/mysql/lib/libmysqlclient.21.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/opt/homebrew/opt/mysql/lib/libmysqlclient.21.dylib' (no such file), '/opt/homebrew/opt/mysql/lib/libmysqlclient.21.dylib' (no such file), '/usr/lib/libmysqlclient.21.dylib' (no such file, not in dyld cache)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/lamidotijjo/Python/Django/demoproject/manage.py", line 22, in <module>
    main()
  File "/Users/lamidotijjo/Python/Django/demoproject/manage.py", line 18, in main
    execute_from_command_line(sys.argv)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/core/management/__init__.py", line 446, in execute_from_command_line
    utility.execute()
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/core/management/__init__.py", line 420, in execute
    django.setup()
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/__init__.py", line 24, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/apps/registry.py", line 116, in populate
    app_config.import_models()
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/apps/config.py", line 269, in import_models
    self.models_module = import_module(models_module_name)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 688, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 883, in exec_module
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/contrib/auth/models.py", line 3, in <module>
    from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/contrib/auth/base_user.py", line 49, in <module>
    class AbstractBaseUser(models.Model):
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/db/models/base.py", line 141, in __new__
    new_class.add_to_class("_meta", Options(meta, app_label))
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/db/models/base.py", line 369, in add_to_class
    value.contribute_to_class(cls, name)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/db/models/options.py", line 231, in contribute_to_class
    self.db_table, connection.ops.max_name_length()
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/utils/connection.py", line 15, in __getattr__
    return getattr(self._connections[self._alias], item)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/utils/connection.py", line 62, in __getitem__
    conn = self.create_connection(alias)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/db/utils.py", line 193, in create_connection
    backend = load_backend(db["ENGINE"])
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/db/utils.py", line 113, in load_backend
    return import_module("%s.base" % backend_name)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/django/db/backends/mysql/base.py", line 15, in <module>
    import MySQLdb as Database
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/MySQLdb/__init__.py", line 24, in <module>
    version_info, _mysql.version_info, _mysql.__file__
NameError: name '_mysql' is not defined

settings.py数据库配置 #

DATABASES = {   
    'default': {   
        'ENGINE': 'django.db.backends.mysql',   
        'NAME': 'mydatabase',   
        'USER': 'root',   
        'PASSWORD': '',   
        'HOST': '127.0.0.1',   
        'PORT': '3306',   
        'OPTIONS': {   
            'init_command': "SET sql_mode='STRICT_TRANS_TABLES'"   
        }   
    }   
}

解决步骤 #

1. 确认MySQL库文件路径

先验证本地MySQL库文件是否存在：

ls /usr/local/mysql-8.0.31-macos12-arm64/lib/

确认输出中包含libmysqlclient.21.dylib。

2. 临时设置环境变量

直接在终端执行以下命令，临时指定库文件路径：

export DYLD_LIBRARY_PATH="/usr/local/mysql-8.0.31-macos12-arm64/lib:$DYLD_LIBRARY_PATH"

然后重新运行python3 manage.py makemigrations测试。

3. 永久配置环境变量

如果临时生效，可将配置写入shell配置文件：

• zsh用户：编辑~/.zshrc，添加上述export命令，执行source ~/.zshrc生效
• bash用户：编辑~/.bash_profile或~/.bashrc，添加后执行source命令生效

4. 重新编译安装mysqlclient（推荐）

卸载现有mysqlclient，编译时指定MySQL路径：

pip3 uninstall mysqlclient -y
pip3 install mysqlclient --global-option=build_ext --global-option="-L/usr/local/mysql-8.0.31-macos12-arm64/lib" --global-option="-I/usr/local/mysql-8.0.31-macos12-arm64/include"

5. 正确创建软链接

因为mysqlclient期望从/opt/homebrew/opt/mysql/lib/加载库，直接链接到该路径：

sudo mkdir -p /opt/homebrew/opt/mysql/lib/
sudo ln -s /usr/local/mysql-8.0.31-macos12-arm64/lib/libmysqlclient.21.dylib /opt/homebrew/opt/mysql/lib/libmysqlclient.21.dylib

内容的提问来源于stack exchange，提问作者Ubuntuer