freedakgmail
41 lines
982 B
Python
41 lines
982 B
Python
"""数据库引擎与会话管理。"""
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from __future__ import annotations
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from collections.abc import Iterator
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from sqlalchemy import create_engine
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from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker
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from app.config import get_settings
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class Base(DeclarativeBase):
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"""所有 ORM 模型的基类。"""
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_engine = None
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_SessionLocal: sessionmaker[Session] | None = None
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def get_engine():
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global _engine
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if _engine is None:
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settings = get_settings()
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_engine = create_engine(settings.database_url, pool_pre_ping=True, future=True)
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return _engine
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def get_sessionmaker() -> sessionmaker[Session]:
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global _SessionLocal
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if _SessionLocal is None:
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_SessionLocal = sessionmaker(bind=get_engine(), expire_on_commit=False)
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return _SessionLocal
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def get_session() -> Iterator[Session]:
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"""FastAPI 依赖注入用的会话生成器。"""
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sm = get_sessionmaker()
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with sm() as session:
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yield session
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