51 lines
1.4 KiB
Python
51 lines
1.4 KiB
Python
"""
|
|
Database engine/session management.
|
|
|
|
Uses SQLAlchemy so the storage backend is a config change, not a code
|
|
change. Today DB_URL points at a local SQLite file. When you're ready
|
|
to move to the MariaDB LXC, set DB_URL in .env to something like:
|
|
|
|
mysql+pymysql://user:[email protected]:3306/order_manager
|
|
|
|
and install PyMySQL (pip install pymysql). Nothing else in the app
|
|
needs to change.
|
|
"""
|
|
from __future__ import annotations
|
|
|
|
from sqlalchemy import create_engine
|
|
from sqlalchemy.orm import sessionmaker, Session
|
|
|
|
from app import config
|
|
from app.models import Base
|
|
|
|
_engine = None
|
|
_SessionLocal = None
|
|
|
|
|
|
def get_engine():
|
|
global _engine
|
|
if _engine is None:
|
|
db_url = config.get("DB_URL", config.DEFAULT_DB_URL)
|
|
connect_args = {}
|
|
if db_url.startswith("sqlite"):
|
|
# allow use across the QThread worker and the UI thread
|
|
connect_args = {"check_same_thread": False}
|
|
_engine = create_engine(db_url, connect_args=connect_args, future=True)
|
|
return _engine
|
|
|
|
|
|
def get_session_factory():
|
|
global _SessionLocal
|
|
if _SessionLocal is None:
|
|
_SessionLocal = sessionmaker(bind=get_engine(), future=True, expire_on_commit=False)
|
|
return _SessionLocal
|
|
|
|
|
|
def init_db() -> None:
|
|
"""Create tables that don't exist yet. Safe to call every startup."""
|
|
Base.metadata.create_all(get_engine())
|
|
|
|
|
|
def get_session() -> Session:
|
|
return get_session_factory()()
|