unshackle/unshackle/core/api/download_worker.py
2026-01-03 18:02:26 +02:00

103 lines
3.2 KiB
Python

"""Standalone worker process entry point for executing download jobs."""
from __future__ import annotations
import json
import logging
import sys
import traceback
from pathlib import Path
from typing import Any, Dict
from .download_manager import _perform_download
log = logging.getLogger("download_worker")
def _read_payload(path: Path) -> Dict[str, Any]:
with path.open("r", encoding="utf-8") as handle:
return json.load(handle)
def _write_result(path: Path, payload: Dict[str, Any]) -> None:
path.parent.mkdir(parents=True, exist_ok=True)
with path.open("w", encoding="utf-8") as handle:
json.dump(payload, handle)
def main(argv: list[str]) -> int:
if len(argv) not in [3, 4]:
print(
"Usage: python -m unshackle.core.api.download_worker <payload_path> <result_path> [progress_path]",
file=sys.stderr,
)
return 2
payload_path = Path(argv[1])
result_path = Path(argv[2])
progress_path = Path(argv[3]) if len(argv) > 3 else None
result: Dict[str, Any] = {}
exit_code = 0
try:
payload = _read_payload(payload_path)
job_id = payload["job_id"]
service = payload["service"]
title_id = payload["title_id"]
params = payload.get("parameters", {})
log.info(f"Worker starting job {job_id} ({service}:{title_id})")
def progress_callback(progress_data: Dict[str, Any]) -> None:
"""Write progress updates to file for main process to read."""
if progress_path:
try:
log.info(f"Writing progress update: {progress_data}")
_write_result(progress_path, progress_data)
log.info(f"Progress update written to {progress_path}")
except Exception as e:
log.error(f"Failed to write progress update: {e}")
output_files = _perform_download(
job_id, service, title_id, params, cancel_event=None, progress_callback=progress_callback
)
result = {"status": "success", "output_files": output_files}
except Exception as exc: # noqa: BLE001 - capture for parent process
from unshackle.core.api.errors import categorize_exception
exit_code = 1
tb = traceback.format_exc()
log.error(f"Worker failed with error: {exc}")
api_error = categorize_exception(
exc,
context={
"service": payload.get("service") if "payload" in locals() else None,
"title_id": payload.get("title_id") if "payload" in locals() else None,
"job_id": payload.get("job_id") if "payload" in locals() else None,
},
)
result = {
"status": "error",
"message": str(exc),
"error_details": api_error.message,
"error_code": api_error.error_code.value,
"traceback": tb,
}
finally:
try:
_write_result(result_path, result)
except Exception as exc: # noqa: BLE001 - last resort logging
log.error(f"Failed to write worker result file: {exc}")
return exit_code
if __name__ == "__main__":
sys.exit(main(sys.argv))