import httpx from fastapi import FastAPI, Request from fastapi.responses import JSONResponse from pydantic import BaseModel from common.http import downstream_client from common.logging_config import configure_logging from common.redis_client import redis_client from common.settings import settings from . import chaos from .scoring import score SERVICE_NAME = "fraud" logger = configure_logging(SERVICE_NAME) app = FastAPI(title=SERVICE_NAME) class ScoreRequest(BaseModel): account_id: str holder_name: str category_id: int | None = None amount_minor: int request_id: str = "unknown" @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: 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"} @app.post("/internal/score") async def score_transaction(body: ScoreRequest): logger.info(f"scoring account {body.account_id} request_id={body.request_id}") await redis_client.incr("fraud:calls_total") if await chaos.blocking_event_loop_enabled(): logger.info(f"blocking_event_loop chaos engaged for request_id={body.request_id}") chaos.synchronous_cpu_work() async with downstream_client(body.request_id) as client: try: resp = await client.post( f"{settings.sanctions_url}/internal/lookup", json={"holder_name": body.holder_name, "request_id": body.request_id}, ) except httpx.TimeoutException: logger.exception(f"sanctions lookup timed out for request_id={body.request_id}") return JSONResponse(status_code=504, content={"error": "sanctions lookup timed out"}) except httpx.RequestError as exc: logger.exception(f"sanctions lookup failed for request_id={body.request_id}: {exc}") return JSONResponse(status_code=502, content={"error": "sanctions lookup failed"}) if resp.status_code >= 300: logger.info(f"sanctions returned {resp.status_code} for request_id={body.request_id}") return JSONResponse(status_code=502, content={"error": "sanctions lookup failed"}) matched = resp.json().get("matched", False) risk_score = score(body.category_id, matched) return {"risk_score": risk_score, "matched": matched}