Initial commit with translated description

scripts/market_series.py

@@ -0,0 +1,86 @@
+#!/usr/bin/env python3
+"""
+market_series.py
+
+Fetch historical series and print CSV to stdout.
+
+Stocks/ETFs/indices: yfinance history (daily)
+FX: derived from ExchangeRate-API open endpoint (daily snapshots not provided here),
+    so we return a simple "latest only" line unless you add a historical FX provider.
+
+Usage:
+  python scripts/market_series.py AAPL --days 30
+  python scripts/market_series.py ^GSPC --days 120
+  python scripts/market_series.py USD/ZAR --days 30
+"""
+
+from __future__ import annotations
+
+import argparse
+import sys
+import re
+from datetime import datetime, timedelta
+from typing import Optional, Tuple
+
+import pandas as pd
+
+
+def _parse_fx_pair(s: str) -> Optional[Tuple[str, str]]:
+    s = s.strip().upper()
+    s = s.replace(" ", "")
+    s = s.replace("-", "/")
+    if "/" in s:
+        parts = s.split("/")
+        if len(parts) == 2 and len(parts[0]) == 3 and len(parts[1]) == 3:
+            return parts[0], parts[1]
+        return None
+    if len(s) == 6 and s.isalpha():
+        return s[:3], s[3:]
+    return None
+
+
+def _stock_series(symbol: str, days: int) -> pd.DataFrame:
+    import yfinance as yf
+
+    end = datetime.utcnow()
+    start = end - timedelta(days=days)
+
+    df = yf.download(symbol, start=start.date().isoformat(), end=end.date().isoformat(), progress=False)
+    if df is None or len(df) == 0:
+        raise RuntimeError(f"No data returned for symbol: {symbol}")
+
+    df = df.reset_index()
+    # Normalize column names (handle MultiIndex tuples from yfinance)
+    cols = {}
+    for c in df.columns:
+        if isinstance(c, tuple):
+            # Flatten tuple to string (e.g., ('Close', 'AAPL') -> 'close')
+            name = "_".join(str(x) for x in c if x).lower().replace(" ", "_")
+        else:
+            name = str(c).lower().replace(" ", "_")
+        cols[c] = name
+    df = df.rename(columns=cols)
+    return df
+
+
+def main() -> None:
+    ap = argparse.ArgumentParser()
+    ap.add_argument("symbol", help="Ticker or FX pair")
+    ap.add_argument("--days", type=int, default=30)
+    args = ap.parse_args()
+
+    fx = _parse_fx_pair(args.symbol)
+    if fx:
+        # Open access endpoint does not provide true historical in this mode.
+        # We intentionally fail loudly so the agent explains the limitation.
+        raise SystemExit(
+            "FX historical series is not supported with the no-key open endpoint. "
+            "Use latest quotes, or add a historical FX provider (paid or other source)."
+        )
+
+    df = _stock_series(args.symbol, args.days)
+    df.to_csv(sys.stdout, index=False)
+
+
+if __name__ == "__main__":
+    main()