trading/shared/fundamentals/cache.py
2026-02-23 21:49:31 +00:00

99 lines
4.1 KiB
Python

"""DB-backed cache for fundamental data."""
from __future__ import annotations
import logging
from datetime import datetime, timezone, timedelta
from sqlalchemy import select
from sqlalchemy.ext.asyncio import async_sessionmaker
from shared.fundamentals.base import FundamentalsProvider
from shared.schemas.trading import FundamentalsSnapshot
from shared.models.fundamentals import Fundamentals
logger = logging.getLogger(__name__)
class CachedFundamentalsProvider:
"""Wraps a FundamentalsProvider with DB-backed caching."""
def __init__(
self,
provider: FundamentalsProvider,
session_factory: async_sessionmaker,
cache_ttl_hours: int = 24,
) -> None:
self._provider = provider
self._session_factory = session_factory
self._cache_ttl = timedelta(hours=cache_ttl_hours)
async def fetch(self, ticker: str) -> FundamentalsSnapshot | None:
cached = await self._load_from_db(ticker)
if cached is not None:
age = datetime.now(timezone.utc) - cached.fetched_at.replace(tzinfo=timezone.utc)
if age < self._cache_ttl:
logger.debug("Cache hit for %s (age=%s)", ticker, age)
return cached
logger.debug("Cache stale for %s (age=%s), refreshing", ticker, age)
result = await self._provider.fetch(ticker)
if result is not None:
await self._save_to_db(result)
return result
async def _load_from_db(self, ticker: str) -> FundamentalsSnapshot | None:
try:
async with self._session_factory() as session:
stmt = select(Fundamentals).where(Fundamentals.ticker == ticker)
row = (await session.execute(stmt)).scalar_one_or_none()
if row is None:
return None
return FundamentalsSnapshot(
ticker=row.ticker,
eps_ttm=row.eps_ttm,
pe_ratio=row.pe_ratio,
peg_ratio=row.peg_ratio,
revenue_growth_yoy=row.revenue_growth_yoy,
profit_margin=row.profit_margin,
debt_to_equity=row.debt_to_equity,
market_cap=row.market_cap,
fetched_at=row.fetched_at,
)
except Exception:
logger.exception("Failed to load fundamentals from DB for %s", ticker)
return None
async def _save_to_db(self, snapshot: FundamentalsSnapshot) -> None:
try:
async with self._session_factory() as session:
stmt = select(Fundamentals).where(Fundamentals.ticker == snapshot.ticker)
existing = (await session.execute(stmt)).scalar_one_or_none()
if existing:
existing.eps_ttm = snapshot.eps_ttm
existing.pe_ratio = snapshot.pe_ratio
existing.peg_ratio = snapshot.peg_ratio
existing.revenue_growth_yoy = snapshot.revenue_growth_yoy
existing.profit_margin = snapshot.profit_margin
existing.debt_to_equity = snapshot.debt_to_equity
existing.market_cap = snapshot.market_cap
existing.fetched_at = snapshot.fetched_at
else:
row = Fundamentals(
ticker=snapshot.ticker,
eps_ttm=snapshot.eps_ttm,
pe_ratio=snapshot.pe_ratio,
peg_ratio=snapshot.peg_ratio,
revenue_growth_yoy=snapshot.revenue_growth_yoy,
profit_margin=snapshot.profit_margin,
debt_to_equity=snapshot.debt_to_equity,
market_cap=snapshot.market_cap,
fetched_at=snapshot.fetched_at,
)
session.add(row)
await session.commit()
logger.debug("Saved fundamentals for %s to DB", snapshot.ticker)
except Exception:
logger.exception("Failed to save fundamentals for %s to DB", snapshot.ticker)