Files
microdao-daarion/services/market-data-service/app/consumers/print.py
Apple c50843933f feat: market-data-service for SenpAI trading agent
New service: real-time market data collection with unified event model.

Architecture:
- Domain events: TradeEvent, QuoteEvent, BookL2Event, HeartbeatEvent
- Provider interface: MarketDataProvider ABC with connect/subscribe/stream/close
- Async EventBus with fan-out to multiple consumers

Providers:
- BinanceProvider: public WebSocket (trades + bookTicker), no API key needed,
  auto-reconnect with exponential backoff, heartbeat timeout detection
- AlpacaProvider: IEX real-time data + paper trading auth,
  dry-run mode when no keys configured (heartbeats only)

Consumers:
- StorageConsumer: SQLite (via SQLAlchemy async) + JSONL append-only log
- MetricsConsumer: Prometheus counters, latency histograms, events/sec gauge
- PrintConsumer: sampled structured logging (1/100 events)

CLI: python -m app run --provider binance --symbols BTCUSDT,ETHUSDT
HTTP: /health, /metrics (Prometheus), /latest?symbol=XXX

Tests: 19/19 passed (Binance parse, Alpaca parse, bus smoke tests)

Config: pydantic-settings + .env, all secrets via environment variables.
Co-authored-by: Cursor <cursoragent@cursor.com>
2026-02-09 11:19:00 -08:00

60 lines
1.8 KiB
Python

"""
PrintConsumer: structured debug logging (sampled).
"""
from __future__ import annotations
import logging
from app.config import settings
from app.domain.events import Event, EventType
logger = logging.getLogger(__name__)
class PrintConsumer:
"""
Logs 1 out of every N events for debugging.
Always logs heartbeats and first event per symbol.
"""
def __init__(self, sample_rate: int | None = None) -> None:
self._sample_rate = sample_rate or settings.log_sample_rate
self._count = 0
self._seen_symbols: set[str] = set()
async def handle(self, event: Event) -> None:
self._count += 1
symbol = getattr(event, "symbol", None)
# Always log heartbeats
if event.event_type == EventType.HEARTBEAT:
logger.info(
"event.heartbeat",
extra={"provider": event.provider},
)
return
# Always log first event for a new symbol
force_log = False
if symbol and symbol not in self._seen_symbols:
self._seen_symbols.add(symbol)
force_log = True
# Sample
if force_log or self._count % self._sample_rate == 0:
extra = {
"provider": event.provider,
"type": event.event_type.value,
"symbol": symbol or "?",
"n": self._count,
}
if event.event_type == EventType.TRADE:
extra["price"] = getattr(event, "price", None)
extra["size"] = getattr(event, "size", None)
elif event.event_type == EventType.QUOTE:
extra["bid"] = getattr(event, "bid", None)
extra["ask"] = getattr(event, "ask", None)
logger.info("event.sample", extra=extra)