document-management/backend/migrations/env.py

"""Alembic运行环境。"""

from __future__ import annotations

import os
from logging.config import fileConfig

from alembic import context
from sqlalchemy import engine_from_config, pool

from dms.config import load_dms_config
from dms.extensions import db
import dms.models  # noqa: F401


config = context.config
if config.config_file_name is not None:
    fileConfig(config.config_file_name)

# 连接串优先级：环境变量 > alembic.ini > load_dms_config默认值。
# 环境变量最高优先，保证测试（conftest注入测试库）不会被ini中的真实地址劫持。
url = (
    os.environ.get("DMS_DATABASE_URL", "").strip()
    or (config.get_main_option("sqlalchemy.url") or "").strip()
    or load_dms_config()["SQLALCHEMY_DATABASE_URI"]
)
config.set_main_option("sqlalchemy.url", url.replace("%", "%%"))
target_metadata = db.metadata


def run_migrations_offline() -> None:
    context.configure(
        url=config.get_main_option("sqlalchemy.url"),
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
        compare_type=True,
        compare_server_default=True,
    )
    with context.begin_transaction():
        context.run_migrations()


def run_migrations_online() -> None:
    connectable = engine_from_config(
        config.get_section(config.config_ini_section, {}),
        prefix="sqlalchemy.",
        poolclass=pool.NullPool,
        isolation_level="READ COMMITTED",
        connect_args={"init_command": "SET time_zone = '+00:00'"},
    )
    with connectable.connect() as connection:
        context.configure(
            connection=connection,
            target_metadata=target_metadata,
            compare_type=True,
            compare_server_default=True,
        )
        with context.begin_transaction():
            context.run_migrations()


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