Files
pyworker/workers/null/client.py
T
Rob Ballantyne 18974873e5 Add null pyworker for queue-driven autoscaling
A PyWorker that does not forward to any model server. POST /reserve holds
the worker busy until the client disconnects (or the duration cap elapses),
so users with their own job queue can drive Vast autoscaling without
exposing inbound model traffic on the instance.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-11 16:48:52 +01:00

71 lines
2.0 KiB
Python

import argparse
import asyncio
import logging
import os
import sys
from vastai import Serverless
logging.basicConfig(
level=logging.DEBUG,
format="%(asctime)s[%(levelname)-5s] %(message)s",
datefmt="%Y-%m-%d %H:%M:%S",
)
log = logging.getLogger(__file__)
ENDPOINT_NAME = "null-prod"
async def reserve(client: Serverless, *, endpoint_name: str, duration: float) -> dict:
"""Hold a Vast worker open for `duration` seconds (or until we disconnect).
The worker counts itself busy for the lifetime of this call, so the
autoscaler will keep it provisioned. Returning here means the reservation
has ended — either the worker hit its duration cap or the request errored.
"""
endpoint = await client.get_endpoint(name=endpoint_name)
payload = {"duration": duration}
log.info("POST /reserve duration=%ss", duration)
resp = await endpoint.request("/reserve", payload, cost=100)
return resp["response"]
def build_arg_parser() -> argparse.ArgumentParser:
p = argparse.ArgumentParser(description="Vast Null PyWorker demo client")
p.add_argument(
"--endpoint",
default=os.environ.get("VAST_ENDPOINT", ENDPOINT_NAME),
help=f"Vast endpoint name (default: {ENDPOINT_NAME})",
)
p.add_argument(
"--duration",
type=float,
default=60.0,
help="Seconds to hold the worker busy (default: 60)",
)
return p
async def main_async():
args = build_arg_parser().parse_args()
print("=" * 60)
print(f"Reserving 1 worker on endpoint '{args.endpoint}' for {args.duration}s")
print("=" * 60)
try:
async with Serverless() as client:
response = await reserve(
client=client,
endpoint_name=args.endpoint,
duration=args.duration,
)
print(f"Reservation result: {response}")
except Exception as e:
log.error("Error during reservation: %s", e, exc_info=True)
sys.exit(1)
if __name__ == "__main__":
asyncio.run(main_async())