feat(signal_v2-phase3a): kis_client REST + 4 integration tests

KISClient: 분봉 (FHKST03010200) + 호가 (FHKST01010200) async REST.
V1 토큰 파일 (signal_v1/data/kis_token.json) read-only 공유, mtime
캐시. 초당 2회 throttle. exponential retry (max 3, 1s/2s/4s).

4 tests pass.

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

signal_v2/kis_client.py

@@ -0,0 +1,155 @@
+"""KIS REST API client — 분봉 + 호가. V1 토큰 read-only 공유."""
+from __future__ import annotations
+import asyncio
+import json
+import logging
+import time
+from datetime import datetime
+from pathlib import Path
+from zoneinfo import ZoneInfo
+
+import httpx
+
+logger = logging.getLogger(__name__)
+KST = ZoneInfo("Asia/Seoul")
+
+_MAX_ATTEMPTS = 3
+_THROTTLE_INTERVAL = 0.5  # 초당 2회 제한
+
+
+class KISClient:
+    """KIS REST (분봉 + 호가). V1 토큰 파일 read-only."""
+
+    def __init__(
+        self,
+        app_key: str, app_secret: str, account: str, is_virtual: bool,
+        v1_token_path: Path,
+        timeout: float = 10.0,
+    ):
+        self._app_key = app_key
+        self._app_secret = app_secret
+        self._account = account
+        self._is_virtual = is_virtual
+        self._v1_token_path = Path(v1_token_path)
+        self._base_url = (
+            "https://openapivts.koreainvestment.com:29443" if is_virtual
+            else "https://openapi.koreainvestment.com:9443"
+        )
+        self._client = httpx.AsyncClient(timeout=timeout)
+        self._token_cache: tuple[str, float] | None = None  # (token, file_mtime)
+        self._last_throttle_at = 0.0
+
+    async def close(self) -> None:
+        await self._client.aclose()
+
+    def _read_v1_token(self) -> str:
+        if not self._v1_token_path.exists():
+            raise RuntimeError(f"V1 token file missing: {self._v1_token_path}")
+        mtime = self._v1_token_path.stat().st_mtime
+        if self._token_cache and self._token_cache[1] == mtime:
+            return self._token_cache[0]
+        data = json.loads(self._v1_token_path.read_text(encoding="utf-8"))
+        token = data.get("access_token", "")
+        if not token:
+            raise RuntimeError("V1 token file has no access_token")
+        self._token_cache = (token, mtime)
+        return token
+
+    async def _throttle(self) -> None:
+        elapsed = time.monotonic() - self._last_throttle_at
+        if elapsed < _THROTTLE_INTERVAL:
+            await asyncio.sleep(_THROTTLE_INTERVAL - elapsed)
+        self._last_throttle_at = time.monotonic()
+
+    def _common_headers(self, tr_id: str) -> dict[str, str]:
+        token = self._read_v1_token()
+        return {
+            "authorization": f"Bearer {token}",
+            "appkey": self._app_key,
+            "appsecret": self._app_secret,
+            "tr_id": tr_id,
+            "custtype": "P",
+        }
+
+    async def _request_with_retry(
+        self, method: str, path: str, tr_id: str, **kwargs,
+    ) -> dict:
+        url = f"{self._base_url}{path}"
+        headers = self._common_headers(tr_id)
+        for attempt in range(_MAX_ATTEMPTS):
+            await self._throttle()
+            try:
+                response = await self._client.request(
+                    method, url, headers=headers, **kwargs
+                )
+                if response.status_code == 429:
+                    if attempt < _MAX_ATTEMPTS - 1:
+                        await asyncio.sleep(2**attempt)
+                        continue
+                    response.raise_for_status()
+                response.raise_for_status()
+                return response.json()
+            except httpx.TimeoutException:
+                if attempt < _MAX_ATTEMPTS - 1:
+                    await asyncio.sleep(2**attempt)
+                    continue
+                raise
+        raise RuntimeError("retry exhausted")
+
+    async def get_minute_ohlcv(self, ticker: str) -> list[dict]:
+        """현재 시점 직전 30개 1분봉 OHLCV (TR_ID FHKST03010200)."""
+        path = "/uapi/domestic-stock/v1/quotations/inquire-time-itemchartprice"
+        params = {
+            "FID_ETC_CLS_CODE": "",
+            "FID_COND_MRKT_DIV_CODE": "J",
+            "FID_INPUT_ISCD": ticker,
+            "FID_INPUT_HOUR_1": datetime.now(KST).strftime("%H%M%S"),
+            "FID_PW_DATA_INCU_YN": "N",
+        }
+        raw = await self._request_with_retry(
+            "GET", path, tr_id="FHKST03010200", params=params,
+        )
+        output2 = raw.get("output2", [])
+        bars = []
+        for row in output2:
+            try:
+                date = row["stck_bsop_date"]
+                hhmmss = row["stck_cntg_hour"]
+                dt = datetime.strptime(f"{date} {hhmmss}", "%Y%m%d %H%M%S").replace(tzinfo=KST)
+                bars.append({
+                    "datetime": dt.isoformat(),
+                    "open": int(row["stck_oprc"]),
+                    "high": int(row["stck_hgpr"]),
+                    "low": int(row["stck_lwpr"]),
+                    "close": int(row["stck_prpr"]),
+                    "volume": int(row["cntg_vol"]),
+                })
+            except (KeyError, ValueError) as e:
+                logger.warning("skip malformed bar for %s: %r", ticker, e)
+        # KIS returns descending; reverse to ascending (most recent last)
+        bars.reverse()
+        return bars
+
+    async def get_asking_price(self, ticker: str) -> dict:
+        """현재 호가 + 매수/매도 잔량 (TR_ID FHKST01010200)."""
+        path = "/uapi/domestic-stock/v1/quotations/inquire-asking-price-exp-ccn"
+        params = {
+            "FID_COND_MRKT_DIV_CODE": "J",
+            "FID_INPUT_ISCD": ticker,
+        }
+        raw = await self._request_with_retry(
+            "GET", path, tr_id="FHKST01010200", params=params,
+        )
+        output1 = raw.get("output1", {})
+        bid_total = int(output1.get("total_bidp_rsqn", 0))
+        ask_total = int(output1.get("total_askp_rsqn", 0))
+        total = bid_total + ask_total
+        bid_ratio = bid_total / total if total > 0 else 0.0
+        current_price = int(output1.get("stck_prpr", 0))
+        return {
+            "bid_total": bid_total,
+            "ask_total": ask_total,
+            "bid_ratio": bid_ratio,
+            "current_price": current_price,
+            "as_of": datetime.now(KST).isoformat(),
+        }