Initial commit: MyMidas personal finance tracker

Full-stack self-hosted finance app with FastAPI backend and React frontend.

Features:
- Accounts, transactions, budgets, investments with GBP base currency
- CSV import with auto-detection for 10 UK bank formats
- ML predictions: spending forecast, net worth projection, Monte Carlo
- 7 selectable themes (Obsidian, Arctic, Midnight, Vault, Terminal, Synthwave, Ledger)
- Receipt/document attachments on transactions (JPEG, PNG, WebP, PDF)
- AES-256-GCM field encryption, RS256 JWT, TOTP 2FA, RLS, audit log
- Encrypted nightly backups + key rotation script
- Mobile-responsive layout with bottom nav

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/services/price_feed_service.py

@@ -0,0 +1,116 @@
+"""
+Live price fetching: yfinance for stocks/ETFs, CoinGecko for crypto.
+Falls back gracefully — never raises, always returns None on failure.
+"""
+import asyncio
+from datetime import date, datetime, timezone, timedelta
+from decimal import Decimal
+from typing import Any
+
+import structlog
+
+logger = structlog.get_logger()
+
+
+async def _run_sync(fn, *args):
+    loop = asyncio.get_event_loop()
+    return await loop.run_in_executor(None, fn, *args)
+
+
+def _fetch_yahoo(symbol: str) -> dict | None:
+    try:
+        import yfinance as yf
+        ticker = yf.Ticker(symbol)
+        info = ticker.fast_info
+        price = getattr(info, "last_price", None) or getattr(info, "regularMarketPrice", None)
+        prev = getattr(info, "previous_close", None)
+        if price is None:
+            return None
+        change_24h = None
+        if prev and prev > 0:
+            change_24h = round((price - prev) / prev * 100, 4)
+        return {
+            "price": Decimal(str(round(price, 8))),
+            "change_24h": Decimal(str(change_24h)) if change_24h is not None else None,
+            "currency": (getattr(info, "currency", None) or "USD").upper(),
+            "name": getattr(info, "long_name", None) or symbol,
+            "exchange": getattr(info, "exchange", None),
+        }
+    except Exception as exc:
+        logger.warning("yahoo_fetch_failed", symbol=symbol, error=str(exc))
+        return None
+
+
+def _fetch_coingecko(coin_id: str) -> dict | None:
+    try:
+        import requests
+        r = requests.get(
+            f"https://api.coingecko.com/api/v3/simple/price",
+            params={"ids": coin_id, "vs_currencies": "usd,gbp", "include_24hr_change": "true"},
+            timeout=10,
+        )
+        r.raise_for_status()
+        data = r.json().get(coin_id, {})
+        if not data:
+            return None
+        return {
+            "price": Decimal(str(data.get("gbp", data.get("usd", 0)))),
+            "change_24h": Decimal(str(round(data.get("gbp_24h_change", 0), 4))),
+            "currency": "GBP",
+            "name": coin_id,
+        }
+    except Exception as exc:
+        logger.warning("coingecko_fetch_failed", coin_id=coin_id, error=str(exc))
+        return None
+
+
+def _fetch_yahoo_history(symbol: str, days: int = 365) -> list[dict]:
+    try:
+        import yfinance as yf
+        ticker = yf.Ticker(symbol)
+        hist = ticker.history(period=f"{days}d", interval="1d")
+        rows = []
+        for ts, row in hist.iterrows():
+            rows.append({
+                "date": ts.date(),
+                "open": Decimal(str(round(float(row["Open"]), 8))),
+                "high": Decimal(str(round(float(row["High"]), 8))),
+                "low": Decimal(str(round(float(row["Low"]), 8))),
+                "close": Decimal(str(round(float(row["Close"]), 8))),
+                "volume": Decimal(str(int(row.get("Volume", 0) or 0))),
+            })
+        return rows
+    except Exception as exc:
+        logger.warning("yahoo_history_failed", symbol=symbol, error=str(exc))
+        return []
+
+
+async def fetch_price(symbol: str, data_source: str, data_source_id: str | None) -> dict | None:
+    if data_source == "coingecko":
+        return await _run_sync(_fetch_coingecko, data_source_id or symbol.lower())
+    return await _run_sync(_fetch_yahoo, symbol)
+
+
+async def fetch_history(symbol: str, days: int = 365) -> list[dict]:
+    return await _run_sync(_fetch_yahoo_history, symbol, days)
+
+
+def search_yahoo(query: str) -> list[dict]:
+    try:
+        import yfinance as yf
+        ticker = yf.Ticker(query)
+        info = ticker.fast_info
+        price = getattr(info, "last_price", None)
+        if price:
+            return [{
+                "symbol": query.upper(),
+                "name": getattr(info, "long_name", None) or query.upper(),
+                "type": "stock",
+                "currency": (getattr(info, "currency", None) or "USD").upper(),
+                "exchange": getattr(info, "exchange", None),
+                "data_source": "yahoo_finance",
+                "data_source_id": None,
+            }]
+    except Exception:
+        pass
+    return []