perf(kline): update detail chart with latest row

backend/app/api/kline.py

@@ -459,51 +459,54 @@ def _attach_ext(resp: dict, repo, symbol: str, ext_columns: Optional[str]) -> di
     return resp
 
 
-def _maybe_inject_live_candle(request: Request, symbol: str, rows: list[dict], asset_type: str = "stock") -> list[dict]:
-    """如果有当日实时 enriched 数据, 用实时数据生成今日蜡烛并追加/覆盖。
+def _latest_live_candle(
+    request: Request,
+    symbol: str,
+    asset_type: str = "stock",
+    *,
+    refresh_asset: bool = True,
+) -> dict | None:
+    """从内存缓存读取单只标的的当日实时 enriched 行。"""
 
-    stock 走 QuoteService 的股票实时缓存; etf 走 ETF enriched 缓存 (开启实时 ETF
-    拉取时为盘中数据, 否则为磁盘最新日, 由下方"非今日不注入"守卫自然跳过)。
-    """
     if asset_type == "stock":
         qs = getattr(request.app.state, "quote_service", None)
         if not qs:
-            return rows
+            return None
         df_today, enriched_date = qs.get_enriched_today()
     elif asset_type == "etf":
-        df_today, enriched_date = request.app.state.repo.get_enriched_latest_asset("etf")
+        df_today, enriched_date = request.app.state.repo.get_enriched_latest_asset(
+            "etf", refresh=refresh_asset,
+        )
     else:
-        return rows
+        return None
     if df_today.is_empty():
-        return rows
+        return None
 
-    # 非交易日（周末/假日）缓存的行情日期 != 今天，跳过注入避免产生重复蜡烛
+    # 非交易日(周末/假日)缓存日期 != 今天, 跳过注入避免产生重复蜡烛
     if not enriched_date or enriched_date != date.today():
-        return rows
+        return None
 
     # 查找该 symbol 的实时 enriched 行
     import polars as pl
     try:
         q = df_today.filter(pl.col("symbol") == symbol).to_dicts()
         if not q:
-            return rows
+            return None
         q = q[0]
-    except Exception:  # noqa: BLE001
-        return rows
+    except Exception:
+        return None
 
     close_price = q.get("close")
     if not close_price or close_price <= 0:
-        return rows
+        return None
 
-    today_str = str(enriched_date)
-
-    # enriched 行已包含 OHLCV + 全套指标, 直接用它
-    # 修复: API 在非交易时段可能返回 open/high/low=0, 用 close 填充避免异常蜡烛
+    # 沿用完整日K接口原有的实时行投影, 避免增量接口形成第二套字段契约。
+    # API 在非交易时段可能返回 open/high/low=0, 用 close 填充避免异常蜡烛。
     raw_open = q.get("open")
     raw_high = q.get("high")
     raw_low = q.get("low")
-    live_row: dict = {
-        "date": today_str,
+    live_row = {
+        "date": str(enriched_date),
         "symbol": symbol,
         "open": raw_open if raw_open and raw_open > 0 else close_price,
         "high": raw_high if raw_high and raw_high > 0 else close_price,
@@ -514,7 +517,6 @@ def _maybe_inject_live_candle(request: Request, symbol: str, rows: list[dict], a
         "change_pct": q.get("change_pct"),
         "is_live": True,
     }
-    # 补上 enriched 的技术指标字段
     for key in ("ma5", "ma10", "ma20", "ma30", "ma60",
                 "macd_dif", "macd_dea", "macd_hist",
                 "kdj_k", "kdj_d", "kdj_j",
@@ -523,11 +525,19 @@ def _maybe_inject_live_candle(request: Request, symbol: str, rows: list[dict], a
                 "atr_14", "vol_ratio_5d"):
         if key in q and q[key] is not None:
             live_row[key] = q[key]
+    return live_row
+
+
+def _maybe_inject_live_candle(request: Request, symbol: str, rows: list[dict], asset_type: str = "stock") -> list[dict]:
+    """如果有当日实时 enriched 数据, 用实时数据生成今日蜡烛并追加/覆盖。"""
+    live_row = _latest_live_candle(request, symbol, asset_type)
+    if live_row is None:
+        return rows
 
     # 如果已有今天的 enriched 行, 覆盖; 否则追加
     found = False
-    for i, r in enumerate(rows):
-        if str(r.get("date")) == today_str:
+    for r in rows:
+        if str(r.get("date")) == live_row["date"]:
             r.update(live_row)
             found = True
             break
@@ -538,6 +548,22 @@ def _maybe_inject_live_candle(request: Request, symbol: str, rows: list[dict], a
     return rows
 
 
+@router.get("/daily/latest")
+def get_daily_latest(
+    request: Request,
+    symbol: str = Query(..., description="标的代码,如 000001.SZ"),
+):
+    """返回内存中的当日单行 K 线, 供详情页实时增量更新。"""
+    repo = request.app.state.repo
+    asset_type = repo.resolve_asset_type(symbol)
+    row = _latest_live_candle(request, symbol, asset_type, refresh_asset=False)
+    return {
+        "symbol": symbol,
+        "row": row,
+        "source": "live" if row is not None else "none",
+    }
+
+
 class DailyBatchRequest:
     """批量日K请求。"""
     symbols: list[str]

backend/tests/test_kline_daily_latest.py

@@ -0,0 +1,140 @@
+"""个股详情日 K 最新行接口测试。"""
+from __future__ import annotations
+
+from datetime import date, timedelta
+
+import polars as pl
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+from app.api.kline import router
+
+
+class _FakeQuoteService:
+    def __init__(self, frame: pl.DataFrame, trade_date: date | None) -> None:
+        self._frame = frame
+        self._trade_date = trade_date
+
+    def get_enriched_today(self):
+        return self._frame, self._trade_date
+
+
+class _FakeRepo:
+    def __init__(
+        self,
+        asset_type: str = "stock",
+        latest_asset: tuple[pl.DataFrame, date | None] | None = None,
+    ) -> None:
+        self.asset_type = asset_type
+        self.latest_asset = latest_asset
+        self.latest_asset_calls = 0
+        self.latest_asset_refresh: bool | None = None
+
+    def resolve_asset_type(self, symbol: str) -> str:
+        return self.asset_type
+
+    def get_enriched_latest_asset(self, asset_type: str, refresh: bool = True):
+        self.latest_asset_calls += 1
+        self.latest_asset_refresh = refresh
+        if self.latest_asset is not None:
+            return self.latest_asset
+        raise AssertionError("stock latest row must use QuoteService's memory cache")
+
+
+def _client(
+    frame: pl.DataFrame,
+    trade_date: date | None,
+    *,
+    asset_type: str = "stock",
+    latest_asset: tuple[pl.DataFrame, date | None] | None = None,
+) -> tuple[TestClient, _FakeRepo]:
+    repo = _FakeRepo(asset_type, latest_asset)
+    app = FastAPI()
+    app.include_router(router)
+    app.state.repo = repo
+    app.state.quote_service = _FakeQuoteService(frame, trade_date)
+    return TestClient(app), repo
+
+
+def _live_frame() -> pl.DataFrame:
+    return pl.DataFrame({
+        "symbol": ["600000.SH"],
+        "date": [date.today()],
+        "open": [10.0],
+        "high": [10.8],
+        "low": [9.9],
+        "close": [10.6],
+        "volume": [123_456.0],
+        "amount": [1_234_560.0],
+        "ma5": [10.2],
+        "signal_limit_up": [False],
+    })
+
+
+def test_daily_latest_returns_only_current_memory_row() -> None:
+    client, repo = _client(_live_frame(), date.today())
+
+    response = client.get("/api/kline/daily/latest", params={"symbol": "600000.SH"})
+
+    assert response.status_code == 200
+    body = response.json()
+    assert body["symbol"] == "600000.SH"
+    assert body["source"] == "live"
+    assert body["row"] == {
+        "symbol": "600000.SH",
+        "date": date.today().isoformat(),
+        "open": 10.0,
+        "high": 10.8,
+        "low": 9.9,
+        "close": 10.6,
+        "volume": 123_456.0,
+        "amount": 1_234_560.0,
+        "change_pct": None,
+        "ma5": 10.2,
+        "is_live": True,
+    }
+    assert repo.latest_asset_calls == 0
+
+
+def test_daily_latest_returns_none_for_stale_cache() -> None:
+    client, _ = _client(_live_frame(), date.today() - timedelta(days=1))
+
+    response = client.get("/api/kline/daily/latest", params={"symbol": "600000.SH"})
+
+    assert response.status_code == 200
+    assert response.json() == {
+        "symbol": "600000.SH",
+        "row": None,
+        "source": "none",
+    }
+
+
+def test_daily_latest_returns_none_when_symbol_is_missing() -> None:
+    client, _ = _client(_live_frame(), date.today())
+
+    response = client.get("/api/kline/daily/latest", params={"symbol": "600001.SH"})
+
+    assert response.status_code == 200
+    assert response.json() == {
+        "symbol": "600001.SH",
+        "row": None,
+        "source": "none",
+    }
+
+
+def test_daily_latest_uses_etf_enriched_cache() -> None:
+    etf = _live_frame().with_columns(pl.lit("510300.SH").alias("symbol"))
+    client, repo = _client(
+        pl.DataFrame(),
+        None,
+        asset_type="etf",
+        latest_asset=(etf, date.today()),
+    )
+
+    response = client.get("/api/kline/daily/latest", params={"symbol": "510300.SH"})
+
+    assert response.status_code == 200
+    assert response.json()["row"]["close"] == 10.6
+    assert response.json()["source"] == "live"
+    assert repo.latest_asset_calls == 1
+    assert repo.latest_asset_refresh is False