feat(analytics): C1 扫描器——fetched_at 水位增量/迟到免疫/幂等/全量回填

Co-Authored-By: Claude Code <noreply@anthropic.com>

yunke-server/tests/test_sensitive.py

@@ -3,8 +3,9 @@ from __future__ import annotations
 
 import datetime as dt
 
+from app.analytics.sensitive import scanner
 from app.analytics.sensitive import words as words_svc
-from app.db.models import Message
+from app.db.models import Message, SensitiveHit, SensitiveScanState
 
 
 async def test_create_and_duplicate(make_client):
@@ -92,3 +93,97 @@ async def test_api_create_empty_word_409(make_client):
     r = await client.post("/api/analytics/sensitive/words",
                           json={"word": "   "})
     assert r.status_code == 409
+
+
+# ---------------------------------------------------------------- C1 scanner
+
+def _msg(msg_id, text, fetched, ts=1756900000000, talker="t1"):
+    return Message(msg_id=msg_id, channel="wechat", owner_account_id="wx1",
+                   talker_id=talker, timestamp=ts, is_send=False, type="text",
+                   text=text, fetched_at=fetched)
+
+
+async def test_scan_incremental_and_idempotent(make_client):
+    async def seed(session):
+        f1 = dt.datetime(2026, 9, 4, 10, 0)
+        session.add(_msg("m1", "聊聊私单", f1))
+        session.add(_msg("m2", "正常", f1))
+        await words_svc.create_word(session, word="私单")
+        await session.commit()
+        r1 = await scanner.run_incremental(session)
+        await session.commit()
+        assert r1["hits"] == 1
+        assert r1["new_watermark"] == f1
+        r2 = await scanner.run_incremental(session)  # 再跑:水位之后无新行
+        await session.commit()
+        assert r2["hits"] == 0
+        from sqlalchemy import func, select
+
+        n = (await session.execute(
+            select(func.count()).select_from(SensitiveHit)
+        )).scalar_one()
+        assert n == 1  # 幂等不重复
+
+    await make_client(seed)
+
+
+async def test_late_arriving_history_scanned(make_client):
+    """迟到数据:timestamp 很老但 fetched_at 新 → 必须被扫到(P2 水位设计)。"""
+    async def seed(session):
+        old = dt.datetime(2026, 9, 1, 8, 0)
+        session.add(_msg("m_old", "历史私单消息", old))
+        await words_svc.create_word(session, word="私单")
+        await session.commit()
+        r1 = await scanner.run_incremental(session)
+        await session.commit()
+        assert r1["hits"] == 1
+        # 迟到行:timestamp 很老(fetched_at 现在)
+        session.add(_msg("m_late", "迟到的私单", dt.datetime(2026, 9, 4, 12, 0),
+                         ts=1767000000000))
+        await session.commit()
+        r2 = await scanner.run_incremental(session)
+        await session.commit()
+        assert r2["hits"] == 1  # 按 fetched_at 水位,迟到历史不漏
+
+    await make_client(seed)
+
+
+async def test_single_char_like_fallback(make_client):
+    async def seed(session):
+        session.add(_msg("m1", "坑爹", dt.datetime(2026, 9, 4, 10, 0)))
+        await words_svc.create_word(session, word="坑")  # 单字
+        await session.commit()
+        r = await scanner.run_incremental(session)
+        await session.commit()
+        assert r["hits"] == 1  # 单字走 LIKE 子串,增量行少语义精确
+
+    await make_client(seed)
+
+
+async def test_disposition_preserved(make_client):
+    """重扫已处置行不覆盖 disposition。"""
+    async def seed(session):
+        session.add(_msg("m1", "私单", dt.datetime(2026, 9, 4, 10, 0)))
+        await words_svc.create_word(session, word="私单")
+        await session.commit()
+        await scanner.run_incremental(session)
+        await session.commit()
+        from sqlalchemy import select
+
+        hit = (await session.execute(
+            select(SensitiveHit)
+        )).scalars().one()
+        hit.disposition = "false_positive"
+        await session.commit()
+        # 重扫同词同消息(水位回拨模拟)
+        st = await session.get(SensitiveScanState, "message_text")
+        st.last_fetched_at = None
+        await session.commit()
+        await scanner.run_incremental(session)
+        await session.commit()
+        hit2 = (await session.execute(
+            select(SensitiveHit)
+        )).scalars().one()
+        assert hit2.disposition == "false_positive"
+
+    await make_client(seed)