Repository · 禁业务逻辑

规则

Repo 内只能有 ORM 调用与字段映射。任何 if / for 业务判断都属于"业务逻辑下沉"，必须搬到 Service。

反例 → 正例

# ❌ Repo 写业务规则
class PresentationRepo:
    async def find_owned_publishable(self, owner_id: UUID) -> list[Presentation]:
        items = await Presentation.filter(owner_id=owner_id).all()
        # 业务判断：什么算 "publishable"
        return [p for p in items if p.slide_count >= 5 and p.theme_id is not None]

# ✅ Repo 只提供查询能力，业务判断在 Service
class PresentationRepo:
    async def find_by_owner_with_min_slides(
        self,
        owner_id: UUID,
        *,
        min_slides: int = 0,
        require_theme: bool = False,
    ) -> list[Presentation]:
        q = Presentation.filter(owner_id=owner_id, slide_count__gte=min_slides)
        if require_theme:
            q = q.filter(theme_id__isnull=False)
        return await q.all()

class PresentationService:
    async def list_publishable(self, owner_id: UUID) -> list[Presentation]:
        # 业务定义 "publishable" = slide_count >= 5 AND has theme
        return await self.repo.find_by_owner_with_min_slides(
            owner_id, min_slides=5, require_theme=True,
        )

差别：业务规则"什么算 publishable"在 Service，Repo 只提供原子查询能力。

哪些算业务规则

Repo 允许做的"业务无关"过滤

# ✅ 通用查询参数
async def find_by_owner(
    self,
    owner_id: UUID,
    *,
    limit: int = 20,
    offset: int = 0,
    order_by: str = "-created_at",
    include_deleted: bool = False,    # 软删除 — 是技术细节而非业务
) -> list[Presentation]: ...

包含 / 排除软删除是技术约束，不算业务。

自检

• [ ] Repo 方法体内无 if / for 业务判断？
• [ ] 业务定义（什么叫"completed"、"publishable"）在 Service？
• [ ] Repo 提供"参数化"的原子查询能力，让 Service 组合？

相关

• 父：./index.md
• 兄弟：crud-contract.md