Files
2026-01-19 10:38:50 +08:00

97 lines
3.0 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
import json
from http import HTTPStatus
from fastapi import APIRouter, Depends, FastAPI, HTTPException, Request
from fastapi.responses import JSONResponse
from vllm.engine.protocol import EngineClient
from vllm.entrypoints.openai.api_server import validate_json_request
from vllm.entrypoints.openai.protocol import (
ErrorResponse,
)
from vllm.entrypoints.serve.elastic_ep.middleware import (
get_scaling_elastic_ep,
set_scaling_elastic_ep,
)
from vllm.logger import init_logger
logger = init_logger(__name__)
def engine_client(request: Request) -> EngineClient:
return request.app.state.engine_client
router = APIRouter()
@router.post(
"/scale_elastic_ep",
dependencies=[Depends(validate_json_request)],
responses={
HTTPStatus.OK.value: {"model": dict},
HTTPStatus.BAD_REQUEST.value: {"model": ErrorResponse},
HTTPStatus.REQUEST_TIMEOUT.value: {"model": ErrorResponse},
HTTPStatus.INTERNAL_SERVER_ERROR.value: {"model": ErrorResponse},
},
)
async def scale_elastic_ep(raw_request: Request):
try:
body = await raw_request.json()
except json.JSONDecodeError as e:
raise HTTPException(status_code=400, detail="Invalid JSON format") from e # noqa: B904
new_data_parallel_size = body.get("new_data_parallel_size")
drain_timeout = body.get("drain_timeout", 120) # Default 2 minutes
if new_data_parallel_size is None:
raise HTTPException(
status_code=400, detail="new_data_parallel_size is required"
)
if not isinstance(new_data_parallel_size, int) or new_data_parallel_size <= 0:
raise HTTPException(
status_code=400,
detail="new_data_parallel_size must be a positive integer",
)
if not isinstance(drain_timeout, int) or drain_timeout <= 0:
raise HTTPException(
status_code=400, detail="drain_timeout must be a positive integer"
)
# Set scaling flag to prevent new requests
set_scaling_elastic_ep(True)
client = engine_client(raw_request)
try:
await client.scale_elastic_ep(new_data_parallel_size, drain_timeout)
return JSONResponse(
{
"message": f"Scaled to {new_data_parallel_size} data parallel engines",
}
)
except TimeoutError as e:
raise HTTPException(
status_code=408,
detail="Scale failed due to request drain timeout "
f"after {drain_timeout} seconds",
) from e
except Exception as e:
logger.error("Scale failed: %s", e)
raise HTTPException(status_code=500, detail="Scale failed") from e
finally:
set_scaling_elastic_ep(False)
@router.post("/is_scaling_elastic_ep")
async def is_scaling_elastic_ep(raw_request: Request):
return JSONResponse({"is_scaling_elastic_ep": get_scaling_elastic_ep()})
def attach_router(app: FastAPI):
app.include_router(router)