feat(notify): 站内通知补齐完成、到期逾期与知识事件

backend/app/services/notify.py

@@ -15,8 +15,11 @@ from __future__ import annotations
 import uuid
 from collections.abc import Iterable
 
+from sqlalchemy import select
+from sqlalchemy.dialects.postgresql import insert as pg_insert
 from sqlalchemy.ext.asyncio import AsyncSession
 
+from ..models import Member
 from ..models_ticket import Notification
 
 TICKET_STATUS_CN = {
@@ -48,6 +51,7 @@ async def notify(
     title: str,
     body: str = "",
     actor_id: uuid.UUID | None = None,
+    dedupe_key: str | None = None,
 ) -> int:
     """给若干人各写一条通知，返回实际写入条数。
 
@@ -67,7 +71,55 @@ async def notify(
                 item_id=item_id,
                 title=title[:120],
                 body=body[:300],
+                dedupe_key=dedupe_key,
             )
         )
         count += 1
     return count
+
+
+async def notify_once(
+    session: AsyncSession,
+    *,
+    ws_id: uuid.UUID,
+    user_id: uuid.UUID | None,
+    kind: str,
+    item_id: uuid.UUID | None,
+    title: str,
+    body: str = "",
+    dedupe_key: str,
+    actor_id: uuid.UUID | None = None,
+) -> bool:
+    """写一条带幂等键的通知；已经写过就跳过，返回是否真的写入。
+
+    后台提醒循环会反复扫同一批任务，靠 `dedupe_key` 的唯一索引把重复挡在数据库层，
+    比"先查再插"少一次竞态。提醒本身不是业务事实，丢了不致命，重复才烦人。
+    """
+    if user_id is None or user_id == actor_id:
+        return False
+    result = await session.execute(
+        pg_insert(Notification)
+        .values(
+            workspace_id=ws_id,
+            user_id=user_id,
+            kind=kind,
+            item_id=item_id,
+            title=title[:120],
+            body=body[:300],
+            dedupe_key=dedupe_key,
+        )
+        .on_conflict_do_nothing()
+    )
+    return result.rowcount > 0
+
+
+async def workspace_admins(session: AsyncSession, ws_id: uuid.UUID) -> list[uuid.UUID]:
+    """工作区里能"发布/把关"的人：owner + admin，只算正常成员。"""
+    rows = await session.execute(
+        select(Member.user_id).where(
+            Member.workspace_id == ws_id,
+            Member.status == "active",
+            Member.role.in_(("owner", "admin")),
+        )
+    )
+    return [row[0] for row in rows]