import asyncio import importlib import inspect import re from contextlib import asynccontextmanager from http import HTTPStatus from typing import Optional, Set import fastapi import uvicorn from fastapi import Request from fastapi.exceptions import RequestValidationError from fastapi.middleware.cors import CORSMiddleware from fastapi.responses import JSONResponse, Response, StreamingResponse from prometheus_client import make_asgi_app from starlette.routing import Mount import vllm import vllm.envs as envs from vllm.engine.arg_utils import AsyncEngineArgs from vllm.engine.async_llm_engine import AsyncLLMEngine from vllm.entrypoints.openai.cli_args import make_arg_parser from vllm.entrypoints.openai.protocol import (ChatCompletionRequest, ChatCompletionResponse, CompletionRequest, EmbeddingRequest, ErrorResponse) from vllm.entrypoints.openai.serving_chat import OpenAIServingChat from vllm.entrypoints.openai.serving_completion import OpenAIServingCompletion from vllm.entrypoints.openai.serving_embedding import OpenAIServingEmbedding from vllm.logger import init_logger from vllm.usage.usage_lib import UsageContext from vllm.utils import FlexibleArgumentParser TIMEOUT_KEEP_ALIVE = 5 # seconds openai_serving_chat: OpenAIServingChat openai_serving_completion: OpenAIServingCompletion openai_serving_embedding: OpenAIServingEmbedding logger = init_logger('vllm.entrypoints.openai.api_server') _running_tasks: Set[asyncio.Task] = set() @asynccontextmanager async def lifespan(app: fastapi.FastAPI): async def _force_log(): while True: await asyncio.sleep(10) await engine.do_log_stats() if not engine_args.disable_log_stats: task = asyncio.create_task(_force_log()) _running_tasks.add(task) task.add_done_callback(_running_tasks.remove) yield app = fastapi.FastAPI(lifespan=lifespan) def parse_args(): parser_text = FlexibleArgumentParser( description="vLLM OpenAI-Compatible RESTful API server.") parser = make_arg_parser(parser_text) return parser.parse_args() # Add prometheus asgi middleware to route /metrics requests route = Mount("/metrics", make_asgi_app()) # Workaround for 307 Redirect for /metrics route.path_regex = re.compile('^/metrics(?P.*)$') app.routes.append(route) @app.exception_handler(RequestValidationError) async def validation_exception_handler(_, exc): err = openai_serving_chat.create_error_response(message=str(exc)) return JSONResponse(err.model_dump(), status_code=HTTPStatus.BAD_REQUEST) @app.get("/health") async def health() -> Response: """Health check.""" await openai_serving_chat.engine.check_health() return Response(status_code=200) @app.get("/api/v1/models") async def show_available_models(): models = await openai_serving_chat.show_available_models() return JSONResponse(content=models.model_dump()) @app.get("/version") async def show_version(): ver = {"version": vllm.__version__} return JSONResponse(content=ver) @app.post("/api/v1/chat/completions") async def create_chat_completion(request: ChatCompletionRequest, raw_request: Request): generator = await openai_serving_chat.create_chat_completion( request, raw_request) if isinstance(generator, ErrorResponse): return JSONResponse(content=generator.model_dump(), status_code=generator.code) if request.stream: return StreamingResponse(content=generator, media_type="text/event-stream") else: assert isinstance(generator, ChatCompletionResponse) return JSONResponse(content=generator.model_dump()) @app.post("/api/v1/completions") async def create_completion(request: CompletionRequest, raw_request: Request): generator = await openai_serving_completion.create_completion( request, raw_request) if isinstance(generator, ErrorResponse): return JSONResponse(content=generator.model_dump(), status_code=generator.code) if request.stream: return StreamingResponse(content=generator, media_type="text/event-stream") else: return JSONResponse(content=generator.model_dump()) @app.post("/api/v1/embeddings") async def create_embedding(request: EmbeddingRequest, raw_request: Request): generator = await openai_serving_embedding.create_embedding( request, raw_request) if isinstance(generator, ErrorResponse): return JSONResponse(content=generator.model_dump(), status_code=generator.code) else: return JSONResponse(content=generator.model_dump()) if __name__ == "__main__": args = parse_args() app.add_middleware( CORSMiddleware, allow_origins=args.allowed_origins, allow_credentials=args.allow_credentials, allow_methods=args.allowed_methods, allow_headers=args.allowed_headers, ) if token := envs.VLLM_API_KEY or args.api_key: @app.middleware("http") async def authentication(request: Request, call_next): root_path = "" if args.root_path is None else args.root_path if request.method == "OPTIONS": return await call_next(request) if not request.url.path.startswith(f"{root_path}/v1"): return await call_next(request) if request.headers.get("Authorization") != "Bearer " + token: return JSONResponse(content={"error": "Unauthorized"}, status_code=401) return await call_next(request) for middleware in args.middleware: module_path, object_name = middleware.rsplit(".", 1) imported = getattr(importlib.import_module(module_path), object_name) if inspect.isclass(imported): app.add_middleware(imported) elif inspect.iscoroutinefunction(imported): app.middleware("http")(imported) else: raise ValueError(f"Invalid middleware {middleware}. " f"Must be a function or a class.") logger.info("vLLM API server version %s", vllm.__version__) logger.info("args: %s", args) if args.served_model_name is not None: served_model_names = args.served_model_name else: served_model_names = [args.model] engine_args = AsyncEngineArgs.from_cli_args(args) engine = AsyncLLMEngine.from_engine_args( engine_args, usage_context=UsageContext.OPENAI_API_SERVER) event_loop: Optional[asyncio.AbstractEventLoop] try: event_loop = asyncio.get_running_loop() except RuntimeError: event_loop = None if event_loop is not None and event_loop.is_running(): # If the current is instanced by Ray Serve, # there is already a running event loop model_config = event_loop.run_until_complete(engine.get_model_config()) else: # When using single vLLM without engine_use_ray model_config = asyncio.run(engine.get_model_config()) openai_serving_chat = OpenAIServingChat(engine, model_config, served_model_names, args.response_role, args.lora_modules, args.chat_template) openai_serving_completion = OpenAIServingCompletion( engine, model_config, served_model_names, args.lora_modules) openai_serving_embedding = OpenAIServingEmbedding(engine, model_config, served_model_names) app.root_path = args.root_path uvicorn.run(app, host=args.host, port=args.port, log_level=args.uvicorn_log_level, timeout_keep_alive=TIMEOUT_KEEP_ALIVE, ssl_keyfile=args.ssl_keyfile, ssl_certfile=args.ssl_certfile, ssl_ca_certs=args.ssl_ca_certs, ssl_cert_reqs=args.ssl_cert_reqs)