beanie 迁移命令抛出 ModuleNotFoundError 即使我将 __init__.py 文件放在各自的目录中

Question

我正在研究 beanie 迁移 文档。从

models.py

文件（如

from app.models.users import User

）导入我的文档时，vs code 不会显示任何错误。但是当我运行

beanie migrate

命令时，它会抛出一条引用消息：

ModuleNotFoundError: No module named app

。我在创建相应目录时放置了

__init__.py

文件。 FastAPI 与它运行良好。

以下是migrations.py文件的编写方式：

from app.models.users import User

class Forward:
    ...


class Backward:
    ...

这是我运行的命令：

beanie migrate -uri 'mongodb://user:pass@host' -db db -p relative/path/to/migrations/directory/

这是我执行后得到的：

Building migration list
Traceback (most recent call last):
  File "/home/alexpy/Desktop/backend/env/bin/beanie", line 8, in <module>
    sys.exit(migrations())
  File "/home/alexpy/Desktop/backend/env/lib/python3.10/site-packages/click/core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
  File "/home/alexpy/Desktop/backend/env/lib/python3.10/site-packages/click/core.py", line 1078, in main
    rv = self.invoke(ctx)
  File "/home/alexpy/Desktop/backend/env/lib/python3.10/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/alexpy/Desktop/backend/env/lib/python3.10/site-packages/click/core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/alexpy/Desktop/backend/env/lib/python3.10/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
  File "/home/alexpy/Desktop/backend/env/lib/python3.10/site-packages/beanie/executors/migrate.py", line 200, in migrate
    asyncio.run(run_migrate(settings))
  File "/usr/lib/python3.10/asyncio/runners.py", line 44, in run
    return loop.run_until_complete(main)
  File "/usr/lib/python3.10/asyncio/base_events.py", line 649, in run_until_complete
    return future.result()
  File "/home/alexpy/Desktop/backend/env/lib/python3.10/site-packages/beanie/executors/migrate.py", line 110, in run_migrate
    root = await MigrationNode.build(settings.path)
  File "/home/alexpy/Desktop/backend/env/lib/python3.10/site-packages/beanie/migrations/runner.py", line 222, in build
    ).load_module((path / name).stem)
  File "<frozen importlib._bootstrap_external>", line 548, in _check_name_wrapper
  File "<frozen importlib._bootstrap_external>", line 1063, in load_module
  File "<frozen importlib._bootstrap_external>", line 888, in load_module
  File "<frozen importlib._bootstrap>", line 290, in _load_module_shim
  File "<frozen importlib._bootstrap>", line 719, in _load
  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 "/home/alexpy/Desktop/backend/app/migrations/20240901100154_users_alter_name.py", line 1, in <module>
    from app.models.users import User
ModuleNotFoundError: No module named 'app'

 - List item

这是我的文件层次结构的样子：

app/
├── __init__.py
├── models/
│   ├── __init__.py
│   └── users.py
├── migrations/
│   ├── __init__.py
│   └── 202409011004_user_0001.py
└── main.py

我还研究了迁移示例文件。在那里，文档类在迁移文件中被重写。 每次需要迁移时，是否都需要重写migrations.py 文件中的模型类？

Answer 1

您可以尝试在运行命令时临时设置 PYTHONPATH：

PYTHONPATH=/home/alexpy/Desktop/backend/app beanie migrate -uri 'mongodb://user:pass@host' -db db -p app/migrations/

或者，您可以永久设置 PYTHONPATH。

作为解决方法，您还可以考虑在迁移文件中使用相对导入。例如：

from ..models.users import User