Files
OpenFin/backend/services/option_chain.py
OpenSquared b0b7f9bfda feat: option
2026-07-18 22:04:43 +02:00

126 lines
4.5 KiB
Python

"""
Real option chain fetcher for the Strategy Builder — reuses the same yfinance
proxy/resolution logic as iv_engine.py (futures/indices → optionable ETFs).
"""
import logging
import math
from datetime import date, datetime
from typing import Any, Dict, List, Optional
import yfinance as yf
from services.iv_engine import _resolve_ticker, _get_current_price
logger = logging.getLogger(__name__)
def _num(v: Any, default: float = 0.0) -> float:
try:
f = float(v)
return default if math.isnan(f) else f
except (TypeError, ValueError):
return default
def _rows_from_df(df) -> List[Dict[str, Any]]:
rows = []
for _, r in df.iterrows():
bid = _num(r.get("bid"))
ask = _num(r.get("ask"))
rows.append({
"strike": _num(r.get("strike")),
"bid": bid,
"ask": ask,
"mid": round((bid + ask) / 2, 4) if (bid > 0 and ask > 0) else _num(r.get("lastPrice")),
"last": _num(r.get("lastPrice")),
"iv": _num(r.get("impliedVolatility")),
"open_interest": int(_num(r.get("openInterest"))),
"volume": int(_num(r.get("volume"))),
})
return sorted(rows, key=lambda x: x["strike"])
def get_chain_slice(symbol: str, target_days: int = 8, n_expiries: int = 3) -> Dict[str, Any]:
"""
Fetch the real option chain for `symbol` — yfinance by default, with an automatic
Saxo fallback for instruments yfinance can't handle (FX/futures options).
Dispatch: a Saxo-formatted symbol (exchange suffix, e.g. "OG:xcme") goes straight to
Saxo; otherwise yfinance is tried first (unchanged, proven path for stocks/ETFs), and
only falls back to Saxo if yfinance fails AND a Saxo connection is available.
"""
if ":" in symbol:
from services.saxo_client import get_chain_slice_saxo
return get_chain_slice_saxo(symbol, target_days, n_expiries)
try:
return _get_chain_slice_yfinance(symbol, target_days, n_expiries)
except ValueError:
from services import saxo_auth
from services.saxo_client import get_chain_slice_saxo
if saxo_auth.get_status().get("connected"):
try:
return get_chain_slice_saxo(symbol, target_days, n_expiries)
except Exception as e:
logger.debug(f"[OptionChain] Saxo fallback failed for {symbol}: {e}")
raise
def _get_chain_slice_yfinance(symbol: str, target_days: int = 8, n_expiries: int = 3) -> Dict[str, Any]:
"""
Fetch the real option chain for `symbol` around a target horizon (days).
Returns the `n_expiries` expirations closest to target_days, each with
normalized calls/puts rows (strike, bid, ask, mid, last, iv, open_interest, volume).
"""
proxy = _resolve_ticker(symbol)
t = yf.Ticker(proxy)
spot = _get_current_price(t)
if not spot:
raise ValueError(f"Impossible d'obtenir le prix spot pour {symbol} ({proxy})")
expirations = t.options
if not expirations:
raise ValueError(f"Aucune chaîne d'options disponible pour {symbol} ({proxy})")
today = date.today()
dated = sorted(
expirations,
key=lambda e: abs((datetime.strptime(e, "%Y-%m-%d").date() - today).days - target_days),
)[:max(1, n_expiries)]
expiries_out = []
for exp in dated:
try:
chain = t.option_chain(exp)
days_to_expiry = (datetime.strptime(exp, "%Y-%m-%d").date() - today).days
expiries_out.append({
"expiry_date": exp,
"days_to_expiry": days_to_expiry,
"calls": _rows_from_df(chain.calls),
"puts": _rows_from_df(chain.puts),
})
except Exception as e:
logger.debug(f"[OptionChain] {proxy} {exp}: {e}")
if not expiries_out:
raise ValueError(f"Aucune chaîne exploitable pour {symbol} ({proxy})")
return {
"symbol": symbol.upper(),
"proxy": proxy,
"spot": round(float(spot), 4),
"expiries": expiries_out,
}
def find_quote(chain_slice: Dict[str, Any], expiry_date: str, strike: float, option_type: str) -> Optional[Dict[str, Any]]:
"""Look up a single contract's quote row within a previously fetched chain slice."""
for exp in chain_slice["expiries"]:
if exp["expiry_date"] != expiry_date:
continue
rows = exp["calls"] if option_type == "call" else exp["puts"]
for row in rows:
if abs(row["strike"] - strike) < 1e-6:
return row
return None