Django - MySQL 集成 Mac M1 Max

Question

I'm relatively new to Django and working on a project. I was about to makemigrations and got the following trace:

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

From what I could gather, from the "NameError: name '_mysql' is not defined error. I had also installed "pip3 install mysqlclient" prior to making migrations. That did not solve the issue.

My settings.py for my db connection is as follows:

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'"   
        }   
    }   
}

I believe that my parameters are correct.

1. Installed mysqlclient via pip3

2. Verfied mysql configuration in settings.py file for django app

3. Googled Stacktrace posted for missing elements.

4. I noticed the following, error might be related to the following:

   ImportError: dlopen(/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/MySQLdb/_mysql.cpython-310-darwin.so, 0x0002): Library not loaded: @rpath/libmysqlclient.21.dylib Referenced from: <1F087C56-18D4-3EC9-8718-BEA0A3ECBAE8> /Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/site-packages/MySQLdb/_mysql.cpython-310-darwin.so Reason: tried: '/System/Volumes/Preboot/Cryptexes/OS@rpath/libmysqlclient.21.dylib' (no such file), '/usr/lib/libmysqlclient.21.dylib' (no such file, not in dyld cache)

Therefore, tried to create a symlink as root:

ln -s /usr/local/mysql-8.0.31-macos12-arm64/lib/libmysqlclient.21.dylib /usr/lib/libmysqlclient.21.dylib

Answer 1

I was able to fix the issue. The issue stemmed from the fact that Django was looking for the following file: "libmysqlclient.21.dylib" in the wrong location. The relative path found in "_mysql.cpython-310-darwin.so" was set to the correct absolute path which on my system is found at "/usr/local/mysql-8.0.31-macos12-arm64/lib/libmysqlclient.21.dylib"

Command used was:

install_name_tool -change @rpath/libmysqlclient.21.dylib /usr/local/mysql-8.0.31-macos12-arm64/lib/libmysqlclient.21.dylib _mysql.cpython-310-darwin.so