Initial MVP for QA asset backend

hy_qa_asset_backend/backend/app/database.py

@@ -0,0 +1,49 @@
+from collections.abc import Generator
+
+from sqlalchemy import create_engine
+from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker
+
+from app.config import get_settings
+
+
+class Base(DeclarativeBase):
+    pass
+
+
+settings = get_settings()
+connect_args = {"check_same_thread": False} if settings.resolved_database_url.startswith("sqlite") else {}
+engine = create_engine(settings.resolved_database_url, connect_args=connect_args, future=True)
+SessionLocal = sessionmaker(bind=engine, autoflush=False, autocommit=False, future=True)
+
+
+def get_db() -> Generator[Session, None, None]:
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()
+
+
+def init_db() -> None:
+    from app import models
+
+    Base.metadata.create_all(bind=engine)
+    with SessionLocal() as db:
+        if not db.query(models.User).first():
+            db.add(
+                models.User(
+                    name="默认审核员",
+                    email="reviewer@example.local",
+                    role=models.UserRole.reviewer,
+                )
+            )
+        defaults = {
+            "risk_policy": "AI 只做初筛，未审核内容不能进入标准问答库或可调用库。",
+            "mock_mode": "true" if settings.mock_mode else "false",
+        }
+        for key, value in defaults.items():
+            exists = db.query(models.SystemSetting).filter(models.SystemSetting.key == key).first()
+            if not exists:
+                db.add(models.SystemSetting(key=key, value=value, description="系统内置非敏感配置"))
+        db.commit()
+