feat(stock): apply webai_cache to portfolio/news/screener-preview (SP-A2)

3 endpoint cache 적용 — /api/webai/portfolio, /api/webai/news-sentiment,
/api/stock/screener/run (preview 모드만, auto는 캐시 미적용).
V1+V2 동시 호출도 NAS에서 1회 계산. web-ai 측 SP-A1 캐시와 2-layer로
작동하여 NAS 인바운드 부담 70% 감소 예상.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

stock/app/conftest.py

@@ -0,0 +1,15 @@
+"""Project-level pytest conftest.
+
+SP-A2: autouse fixture that resets all webai_cache TTLCaches between tests
+so screener/portfolio/news cache state does not leak across test cases.
+"""
+import pytest
+from app import webai_cache
+
+
+@pytest.fixture(autouse=True)
+def _reset_webai_cache():
+    webai_cache.PORTFOLIO_CACHE.clear()
+    webai_cache.NEWS_CACHE.clear()
+    webai_cache.SCREENER_CACHE.clear()
+    yield

stock/app/main.py

@@ -25,6 +25,7 @@ from .scraper import fetch_market_news, fetch_major_indices
 from .price_fetcher import get_current_prices, get_current_prices_detail
 from .ai_summarizer import summarize_news, OllamaError
 from .auth import verify_webai_key
+from . import webai_cache
 
 app = FastAPI()
 
@@ -418,8 +419,16 @@ def _augment_portfolio_with_pnl_pct(raw: dict) -> dict:
 
 @app.get("/api/webai/portfolio", dependencies=[Depends(verify_webai_key)])
 def get_webai_portfolio():
-    """web-ai 전용 portfolio (인증 필수, pnl_pct 비율 필드 추가)."""
-    return _augment_portfolio_with_pnl_pct(get_portfolio())
+    """web-ai 전용 portfolio (인증 필수, pnl_pct 비율 필드 추가).
+
+    SP-A2 server-side TTLCache 적용. V1+V2 동시 호출도 NAS에서 1회 계산.
+    """
+    cached = webai_cache.cache_get_portfolio()
+    if cached is not None:
+        return cached
+    result = _augment_portfolio_with_pnl_pct(get_portfolio())
+    webai_cache.cache_set_portfolio(result)
+    return result
 
 
 def _fetch_news_sentiment_dump(date: str | None) -> dict:
@@ -466,8 +475,16 @@ def _fetch_news_sentiment_dump(date: str | None) -> dict:
 
 @app.get("/api/webai/news-sentiment", dependencies=[Depends(verify_webai_key)])
 def get_webai_news_sentiment(date: str | None = None):
-    """web-ai 전용 news sentiment 일별 dump."""
-    return _fetch_news_sentiment_dump(date)
+    """web-ai 전용 news sentiment 일별 dump.
+
+    SP-A2 server-side TTLCache 적용. date 파라미터별로 별도 슬롯.
+    """
+    cached = webai_cache.cache_get_news(date)
+    if cached is not None:
+        return cached
+    result = _fetch_news_sentiment_dump(date)
+    webai_cache.cache_set_news(date, result)
+    return result
 
 
 @app.post("/api/portfolio", status_code=201)

stock/app/screener/router.py

@@ -12,6 +12,7 @@ from fastapi import APIRouter, HTTPException
 
 from . import schemas
 from .registry import NODE_REGISTRY, GATE_REGISTRY
+from .. import webai_cache
 
 
 router = APIRouter(prefix="/api/stock/screener")
@@ -173,6 +174,12 @@ def _persist_run(conn, asof, mode, weights, node_params, gate_params, top_n,
 @router.post("/run", response_model=schemas.RunResponse)
 def post_run(body: schemas.RunRequest):
     from .registry import NODE_REGISTRY as _NR, GATE_REGISTRY as _GR
+    # SP-A2 — preview 모드는 web-ai/frontend 폴링이라 캐시 적용.
+    # auto 모드는 실제 운영 트리거(휴장일 게이트 등)라 캐시 미적용.
+    if body.mode == "preview":
+        cached = webai_cache.cache_get_screener(body.mode, body.top_n, body.weights)
+        if cached is not None:
+            return cached
     started_at = dt.datetime.utcnow().isoformat()
     with _conn() as c:
         asof = _resolve_asof(body.asof, c)
@@ -231,7 +238,7 @@ def post_run(body: schemas.RunRequest):
             top_n=top_n, rows=result.rows, run_id=run_id,
         )
 
-        return schemas.RunResponse(
+        response = schemas.RunResponse(
             asof=asof.isoformat(), mode=body.mode, status="success",
             run_id=run_id, survivors_count=result.survivors_count,
             weights=weights, top_n=top_n,
@@ -239,6 +246,10 @@ def post_run(body: schemas.RunRequest):
             telegram_payload=schemas.TelegramPayload(**payload),
             warnings=result.warnings,
         )
+        # SP-A2 — preview 모드 결과 캐시 저장.
+        if body.mode == "preview":
+            webai_cache.cache_set_screener(body.mode, body.top_n, body.weights, response)
+        return response
 
 
 # ---------- /snapshot/refresh ----------

stock/app/test_webai_cache.py

@@ -0,0 +1,67 @@
+"""SP-A2 — webai_cache module의 cache hit/miss + key 분기 검증."""
+import time
+import pytest
+from app.webai_cache import (
+    PORTFOLIO_CACHE, NEWS_CACHE, SCREENER_CACHE,
+    cache_get_portfolio, cache_set_portfolio,
+    cache_get_news, cache_set_news,
+    cache_get_screener, cache_set_screener,
+    _screener_key,
+)
+
+
+def _clear_all():
+    PORTFOLIO_CACHE.clear()
+    NEWS_CACHE.clear()
+    SCREENER_CACHE.clear()
+
+
+def test_portfolio_cache_miss_then_hit():
+    _clear_all()
+    assert cache_get_portfolio() is None
+    cache_set_portfolio({"holdings": [], "cash": 0})
+    assert cache_get_portfolio() == {"holdings": [], "cash": 0}
+
+
+def test_news_cache_key_by_date():
+    """date가 다르면 별도 캐시 슬롯."""
+    _clear_all()
+    cache_set_news("2026-05-18", {"count": 5})
+    cache_set_news("2026-05-17", {"count": 3})
+    assert cache_get_news("2026-05-18") == {"count": 5}
+    assert cache_get_news("2026-05-17") == {"count": 3}
+    assert cache_get_news("2026-05-16") is None  # not cached
+
+
+def test_news_cache_latest_key_normalized():
+    """date=None은 'latest' 키로 정규화되어 동일 슬롯."""
+    _clear_all()
+    cache_set_news(None, {"count": 9})
+    assert cache_get_news(None) == {"count": 9}
+
+
+def test_screener_key_includes_mode_and_top_n():
+    """screener key는 mode + top_n + weights hash로 분기."""
+    k_preview = _screener_key("preview", 20, None)
+    k_preview_w = _screener_key("preview", 20, {"news": 0.3})
+    k_auto = _screener_key("auto", 20, None)
+    assert k_preview != k_preview_w
+    assert k_preview != k_auto
+
+
+def test_screener_cache_roundtrip():
+    _clear_all()
+    payload = {"asof": "2026-05-18", "survivors_count": 17}
+    cache_set_screener("preview", 20, None, payload)
+    assert cache_get_screener("preview", 20, None) == payload
+    assert cache_get_screener("preview", 20, {"news": 0.3}) is None
+
+
+def test_ttl_expiry_portfolio():
+    """짧은 ttl로 만료 확인 — 직접 시간 조작 대신 TTLCache 내부 동작 신뢰."""
+    from cachetools import TTLCache
+    short = TTLCache(maxsize=1, ttl=0.1)  # 0.1초
+    short["result"] = "x"
+    assert short.get("result") == "x"
+    time.sleep(0.2)
+    assert short.get("result") is None

stock/app/webai_cache.py

@@ -0,0 +1,68 @@
+"""SP-A2 — NAS stock의 /api/webai/* 엔드포인트 in-memory TTLCache.
+
+web-ai 측 캐시(stock_client._TTL)가 miss됐을 때도 NAS에서 같은 데이터를
+KIS·LLM 재호출 없이 즉시 반환하기 위한 2-layer 캐시의 server 측.
+V1+V2가 동시 호출해도 NAS는 1회만 계산.
+
+TTL 정책 (spec §10 SP-A2):
+- portfolio:  120s (web-ai TTL 180s 보다 짧게 — 변경 감지 가능)
+- news:       600s (sentiment는 일 단위)
+- screener:   180s
+"""
+from __future__ import annotations
+
+import hashlib
+import json
+from typing import Any, Optional
+
+from cachetools import TTLCache
+
+
+PORTFOLIO_CACHE: TTLCache = TTLCache(maxsize=1, ttl=120.0)
+NEWS_CACHE: TTLCache = TTLCache(maxsize=10, ttl=600.0)
+SCREENER_CACHE: TTLCache = TTLCache(maxsize=10, ttl=180.0)
+
+
+# ----- portfolio -----
+
+def cache_get_portfolio() -> Optional[Any]:
+    return PORTFOLIO_CACHE.get("result")
+
+
+def cache_set_portfolio(value: Any) -> None:
+    PORTFOLIO_CACHE["result"] = value
+
+
+# ----- news-sentiment -----
+
+def _news_key(date: Optional[str]) -> str:
+    return date if date else "latest"
+
+
+def cache_get_news(date: Optional[str]) -> Optional[Any]:
+    return NEWS_CACHE.get(_news_key(date))
+
+
+def cache_set_news(date: Optional[str], value: Any) -> None:
+    NEWS_CACHE[_news_key(date)] = value
+
+
+# ----- screener -----
+
+def _screener_key(mode: str, top_n: int, weights: Optional[dict]) -> str:
+    """mode + top_n + weights canonical hash. weights 객체 동등성을 키로."""
+    if weights is None:
+        w_repr = "none"
+    else:
+        # canonical: sorted keys → md5 hex (긴 weights도 짧은 키로)
+        canon = json.dumps(weights, sort_keys=True, ensure_ascii=False)
+        w_repr = hashlib.md5(canon.encode("utf-8")).hexdigest()[:12]
+    return f"{mode}:{top_n}:{w_repr}"
+
+
+def cache_get_screener(mode: str, top_n: int, weights: Optional[dict]) -> Optional[Any]:
+    return SCREENER_CACHE.get(_screener_key(mode, top_n, weights))
+
+
+def cache_set_screener(mode: str, top_n: int, weights: Optional[dict], value: Any) -> None:
+    SCREENER_CACHE[_screener_key(mode, top_n, weights)] = value

stock/requirements.txt

@@ -11,4 +11,5 @@ finance-datareader==0.9.110
 lxml==6.1.0
 pytest==8.3.2
 pytest-asyncio==0.24.0
+cachetools>=5.3