meal-order-manager/src/server/worker.py

"""SQS long-poll consumer. One process per task, not per gunicorn worker."""

from __future__ import annotations

import json
import logging
import os
import signal
import sys
import time

import boto3

from server.jobs import run_job

logger = logging.getLogger(__name__)
logging.basicConfig(level=logging.INFO, stream=sys.stderr)

_running = True


def _stop(_signum, _frame) -> None:
    global _running
    _running = False


def main() -> None:
    signal.signal(signal.SIGTERM, _stop)
    signal.signal(signal.SIGINT, _stop)

    queue_url = os.environ.get("JOBS_QUEUE_URL", "").strip()
    if not queue_url:
        logger.info("JOBS_QUEUE_URL unset; worker idle")
        while _running:
            time.sleep(1)
        return
    sqs = boto3.client("sqs")
    logger.info("Polling jobs queue")
    while _running:
        resp = sqs.receive_message(
            QueueUrl=queue_url,
            MaxNumberOfMessages=1,
            WaitTimeSeconds=20,
            VisibilityTimeout=180,
        )
        for msg in resp.get("Messages", []):
            receipt = msg["ReceiptHandle"]
            try:
                payload = json.loads(msg["Body"])
                result = run_job(payload)
                logger.info("job result %s", result)
                sqs.delete_message(QueueUrl=queue_url, ReceiptHandle=receipt)
            except Exception:
                logger.exception("job failed; leaving message for retry")


if __name__ == "__main__":
    main()