LedgerLine/services/notifier/app.py

from contextlib import asynccontextmanager

import asyncio

from fastapi import FastAPI, Request
from fastapi.responses import JSONResponse
from opentelemetry.instrumentation.fastapi import FastAPIInstrumentor
from opentelemetry.instrumentation.sqlalchemy import SQLAlchemyInstrumentor

from common.db import engine
from common.logging_config import configure_logging
from common.redis_client import redis_client
from common.telemetry import setup_telemetry

from . import consumer

SERVICE_NAME = "notifier"
logger = configure_logging(SERVICE_NAME)
setup_telemetry(service_name=SERVICE_NAME)


@asynccontextmanager
async def lifespan(app: FastAPI):
    task = asyncio.create_task(consumer.run())
    yield
    task.cancel()


app = FastAPI(title=SERVICE_NAME, lifespan=lifespan)

FastAPIInstrumentor.instrument_app(
    app,
    excluded_urls="/healthz",
    exclude_spans=["receive", "send"],
)
SQLAlchemyInstrumentor().instrument(engines=[engine.sync_engine])


@app.get("/")
async def root():
    return {"service": SERVICE_NAME, "version": "0.1.0"}


@app.get("/healthz")
async def healthz(request: Request):
    if request.headers.get("X-Ledgerline-Probe") == "chatty-health":
        logger.info("received chatty-health healthz probe from gateway")
    return {"status": "ok", "service": SERVICE_NAME}


@app.get("/readyz")
async def readyz():
    try:
        async with engine.connect() as conn:
            await conn.exec_driver_sql("SELECT 1")
        await redis_client.ping()
    except Exception as exc:
        logger.exception(f"readyz check failed: {exc}")
        return JSONResponse(status_code=503, content={"status": "unavailable"})
    return {"status": "ok"}