增加k线图

backend/app/kline_store.py

@@ -0,0 +1,93 @@
+"""日 K 线：优先 SQLite 本地库，不足或过期再请求币安。"""
+
+import logging
+from datetime import datetime
+
+from .binance import binance_client
+from .config import settings
+from .db import get_daily_klines_from_db, get_kline_meta, save_daily_klines
+from .exceptions import BinanceRateLimitedError
+
+logger = logging.getLogger(__name__)
+
+
+def _is_db_fresh(symbol: str, min_bars: int) -> bool:
+    meta = get_kline_meta(symbol)
+    if not meta or meta.get("bar_count", 0) < min_bars:
+        return False
+    try:
+        last_fetch = datetime.fromisoformat(meta["last_fetch_at"])
+    except ValueError:
+        return False
+    age = (datetime.now() - last_fetch).total_seconds()
+    return age < settings.chart_cache_minutes * 60
+
+
+async def sync_daily_klines(symbol: str, limit: int | None = None) -> list[dict]:
+    """从币安拉取并写入本地库。"""
+    sym = symbol.upper()
+    n = min(limit or settings.chart_kline_limit, 1500)
+    candles = await binance_client.get_daily_klines(sym, n)
+    save_daily_klines(sym, candles)
+    logger.info("Saved %d daily klines for %s to DB", len(candles), sym)
+    return candles
+
+
+async def get_daily_candles(
+    symbol: str,
+    limit: int | None = None,
+    force_refresh: bool = False,
+) -> tuple[list[dict], str]:
+    """
+    返回 (candles, source)。
+    source: db | db_stale | binance
+    """
+    sym = symbol.upper().strip()
+    n = min(limit or settings.chart_kline_limit, 1500)
+    min_bars = min(n, 50)
+
+    if not force_refresh and _is_db_fresh(sym, min_bars):
+        candles = get_daily_klines_from_db(sym, n)
+        if len(candles) >= min_bars:
+            return candles, "db"
+
+    stored = get_daily_klines_from_db(sym, n)
+    if binance_client.is_rate_limited():
+        if stored:
+            logger.warning("Rate limited, serve stale DB klines for %s", sym)
+            return stored, "db_stale"
+        raise BinanceRateLimitedError(binance_client.rate_limit_remaining_sec(), sym)
+
+    try:
+        candles = await sync_daily_klines(sym, n)
+        return candles, "binance"
+    except BinanceRateLimitedError:
+        if stored:
+            return stored, "db_stale"
+        raise
+    except Exception:
+        if stored:
+            return stored, "db_stale"
+        raise
+
+
+async def prefetch_symbols(symbols: list[str]) -> None:
+    """后台预拉 Top 币种日 K 入库（串行，避免 418）。"""
+    seen: set[str] = set()
+    for raw in symbols:
+        sym = raw.upper().strip()
+        if not sym or sym in seen or not sym.endswith("USDT"):
+            continue
+        seen.add(sym)
+        if _is_db_fresh(sym, min(50, settings.chart_kline_limit)):
+            continue
+        if binance_client.is_rate_limited():
+            logger.warning("Prefetch stopped — rate limited")
+            break
+        try:
+            await sync_daily_klines(sym)
+        except BinanceRateLimitedError:
+            logger.warning("Prefetch rate limited at %s", sym)
+            break
+        except Exception as e:
+            logger.warning("Prefetch %s failed: %s", sym, e)