"""FastAPI 依赖：源库 / 目标库会话。"""
from collections.abc import Iterator

from sqlalchemy.orm import Session

from app.core.database import SourceSessionLocal, TargetSessionLocal


def get_source_db() -> Iterator[Session]:
    """FastAPI 依赖：源库（只读）会话。"""
    db = SourceSessionLocal()
    try:
        yield db
    finally:
        db.close()


def get_target_db() -> Iterator[Session]:
    """FastAPI 依赖：目标库会话。"""
    db = TargetSessionLocal()
    try:
        yield db
    finally:
        db.close()