Alembic 不使用 asyncio 初始化

Question

我无法运行：*alembic revision --autogenerate -m "initial revision 导致面对：

File "/home/me/PycharmProjects/vpnbot_via_dialog/migration/env.py", line 7, in <module>
  from sqlalchemy.ext.asyncio import AsyncAttrs, async_sessionmaker, create_async_engine

ImportError: cannot import name 'AsyncAttrs' from 'sqlalchemy.ext.asyncio' (/usr/lib/python3/dist-packages/sqlalchemy/ext/asyncio/__init__.py

Alembic 1.13.3
sqlalchemy 2.0.35
python 3.12

env.py代码：

import asyncio
from logging.config import fileConfig

from sqlalchemy import pool
from sqlalchemy.engine import Connection
from sqlalchemy.ext.asyncio import async_engine_from_config
from sqlalchemy.ext.asyncio import AsyncAttrs, async_sessionmaker, create_async_engine


from alembic import context
from bot.db.database import Base, DATABASE_URL
from bot.db.models import Users, Configs, Servers

# this is the Alembic Config object, which provides
# access to the values within the .ini file in use.
config = context.config
config.set_main_option("sqlalchemy.url",DATABASE_URL)
# Interpret the config file for Python logging.
# This line sets up loggers basically.
if config.config_file_name is not None:
    fileConfig(config.config_file_name)

# add your model's MetaData object here
# for 'autogenerate' support
# from myapp import mymodel
# target_metadata = mymodel.Base.metadata
target_metadata = Base.metadata

# other values from the config, defined by the needs of env.py,
# can be acquired:
# my_important_option = config.get_main_option("my_important_option")
# ... etc.


def run_migrations_offline() -> None:
    """Run migrations in 'offline' mode.

    This configures the context with just a URL
    and not an Engine, though an Engine is acceptable
    here as well.  By skipping the Engine creation
    we don't even need a DBAPI to be available.

    Calls to context.execute() here emit the given string to the
    script output.

    """
    url = config.get_main_option("sqlalchemy.url")
    context.configure(
        url=url,
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
    )

    with context.begin_transaction():
        context.run_migrations()


def do_run_migrations(connection: Connection) -> None:
    context.configure(connection=connection, target_metadata=target_metadata)

    with context.begin_transaction():
        context.run_migrations()


async def run_async_migrations() -> None:
    """In this scenario we need to create an Engine
    and associate a connection with the context.

    """

    connectable = async_engine_from_config(
        config.get_section(config.config_ini_section, {}),
        prefix="sqlalchemy",
        poolclass=pool.NullPool,
    )

    async with connectable.connect() as connection:
        await connection.run_sync(do_run_migrations)

    await connectable.dispose()


def run_migrations_online() -> None:
    """Run migrations in 'online' mode."""

    asyncio.run(run_async_migrations())


if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()

数据库.py代码：

from datetime import datetime
import asyncio

from sqlalchemy import ARRAY, ForeignKey
from sqlalchemy.dialects.postgresql import array
from sqlalchemy.orm import  declarative_base, Mapped, relationship
from sqlalchemy.ext.asyncio import AsyncAttrs, async_sessionmaker, create_async_engine
from sqlalchemy.testing.schema import mapped_column

from bot.config.config import settings


DATABASE_URL = settings.get_db_url()

engine = create_async_engine(url=DATABASE_URL)
async_session_maker = async_sessionmaker(engine, expire_on_commit=False)

# Base class for models
class Base(AsyncAttrs, declarative_base()):
    __abstract__ = True

仅尝试重新安装 libs、python env（假设操作系统存在问题）。谷歌无法提供帮助。

此命令 (**) 必须创建一个包含对数据库架构的更改的转换文件（Python 脚本）。如果在当前数据库中使用 SQLAlchemy 模型发现更改，它们将在此文件的架构中列出。初次修改是第一次修改方案。
但它抛出错误。

Answer 1

答案是：Alembic：alembic修订显示导入错误之后我还添加了“。”到 env.py def run_async_migrations() 中的前缀 =“sqlalchemy”。