Files
tgex-backend/shared/postgres/postgres_helper.py
Artem Tsyrulnikov 3800c72662 init
2025-11-08 19:10:40 +03:00

118 lines
3.6 KiB
Python

import logging
from collections.abc import AsyncGenerator
from contextlib import asynccontextmanager
from pathlib import Path
import pydantic
from sqlalchemy import text
from sqlalchemy.ext.asyncio import (
AsyncEngine,
AsyncSession,
async_sessionmaker,
create_async_engine,
)
class DatabaseConfig(pydantic.BaseModel):
URL: pydantic.PostgresDsn
ECHO: bool = False
ECHO_POOL: bool = False
POOL_SIZE: int = 50
MAX_OVERFLOW: int = 10
class DatabaseHelper:
def __init__(self, config: DatabaseConfig, migrations_path: str = 'migration/versions') -> None:
self.config = config
self.migrations_path = migrations_path
self.engine: AsyncEngine | None = None
self.session_factory: async_sessionmaker[AsyncSession] | None = None
async def connect(self) -> None:
if self.engine is not None:
logging.warning('Database already connected')
return
self.engine = create_async_engine(
url=str(self.config.URL),
echo=self.config.ECHO,
echo_pool=self.config.ECHO_POOL,
pool_size=self.config.POOL_SIZE,
max_overflow=self.config.MAX_OVERFLOW,
)
self.session_factory = async_sessionmaker(
bind=self.engine,
autoflush=False,
autocommit=False,
expire_on_commit=False,
)
await self.ping()
await self._check_migrations()
logging.info('Database initialized')
async def ping(self) -> None:
try:
async with self.session_getter() as session:
await session.execute(text('SELECT 1'))
except Exception as e:
logging.error(f'Database ping failed: {e}')
async def close(self) -> None:
if self.engine is None:
logging.warning('Database already closed')
return
await self.engine.dispose()
self.engine = None
self.session_factory = None
logging.info('Database closed')
@asynccontextmanager
async def session_getter(self) -> AsyncGenerator[AsyncSession]:
"""Контекстный менеджер для получения сессии"""
if self.session_factory is None:
raise RuntimeError('Database not connected. Call connect() first.')
async with self.session_factory() as session:
yield session
async def _check_migrations(self) -> None:
migrations_dir = Path(self.migrations_path)
if not migrations_dir.exists():
return
latest_file = next(
(
f
for f in sorted(migrations_dir.glob('*.py'), reverse=True)
if f.name != '__init__.py'
),
None,
)
if not latest_file:
return
latest_version = latest_file.stem.split('_')[0]
async with self.session_getter() as session:
result = await session.execute(
text(
"SELECT EXISTS (SELECT FROM information_schema.tables WHERE table_name = 'alembic_version')"
)
)
if not result.scalar():
logging.error('Migrations not applied. Run: alembic upgrade head')
return
result = await session.execute(text('SELECT version_num FROM alembic_version'))
current_version = result.scalar()
if current_version != latest_version:
logging.warning(
f'Database version {current_version} is outdated (latest: {latest_version}). Run: alembic upgrade head'
)