[Frontend] Reapply "Factor out code for running uvicorn" (#7095)

vllm/entrypoints/api_server.py

@@ -5,21 +5,23 @@ For production use, we recommend using our OpenAI compatible server.
 We are also not going to accept PRs modifying this file, please
 change `vllm/entrypoints/openai/api_server.py` instead.
 """
-
+import asyncio
 import json
 import ssl
-from typing import AsyncGenerator
+from argparse import Namespace
+from typing import Any, AsyncGenerator, Optional
 
-import uvicorn
 from fastapi import FastAPI, Request
 from fastapi.responses import JSONResponse, Response, StreamingResponse
 
 from vllm.engine.arg_utils import AsyncEngineArgs
 from vllm.engine.async_llm_engine import AsyncLLMEngine
+from vllm.entrypoints.launcher import serve_http
 from vllm.logger import init_logger
 from vllm.sampling_params import SamplingParams
 from vllm.usage.usage_lib import UsageContext
 from vllm.utils import FlexibleArgumentParser, random_uuid
+from vllm.version import __version__ as VLLM_VERSION
 
 logger = init_logger("vllm.entrypoints.api_server")
 
@@ -81,6 +83,53 @@ async def generate(request: Request) -> Response:
     return JSONResponse(ret)
 
 
+def build_app(args: Namespace) -> FastAPI:
+    global app
+
+    app.root_path = args.root_path
+    return app
+
+
+async def init_app(
+    args: Namespace,
+    llm_engine: Optional[AsyncLLMEngine] = None,
+) -> FastAPI:
+    app = build_app(args)
+
+    global engine
+
+    engine_args = AsyncEngineArgs.from_cli_args(args)
+    engine = (llm_engine
+              if llm_engine is not None else AsyncLLMEngine.from_engine_args(
+                  engine_args, usage_context=UsageContext.API_SERVER))
+
+    return app
+
+
+async def run_server(args: Namespace,
+                     llm_engine: Optional[AsyncLLMEngine] = None,
+                     **uvicorn_kwargs: Any) -> None:
+    logger.info("vLLM API server version %s", VLLM_VERSION)
+    logger.info("args: %s", args)
+
+    app = await init_app(args, llm_engine)
+
+    shutdown_task = await serve_http(
+        app,
+        host=args.host,
+        port=args.port,
+        log_level=args.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,
+        **uvicorn_kwargs,
+    )
+
+    await shutdown_task
+
+
 if __name__ == "__main__":
     parser = FlexibleArgumentParser()
     parser.add_argument("--host", type=str, default=None)
@@ -105,25 +154,5 @@ if __name__ == "__main__":
     parser.add_argument("--log-level", type=str, default="debug")
     parser = AsyncEngineArgs.add_cli_args(parser)
     args = parser.parse_args()
-    engine_args = AsyncEngineArgs.from_cli_args(args)
-    engine = AsyncLLMEngine.from_engine_args(
-        engine_args, usage_context=UsageContext.API_SERVER)
 
-    app.root_path = args.root_path
-
-    logger.info("Available routes are:")
-    for route in app.routes:
-        if not hasattr(route, 'methods'):
-            continue
-        methods = ', '.join(route.methods)
-        logger.info("Route: %s, Methods: %s", route.path, methods)
-
-    uvicorn.run(app,
-                host=args.host,
-                port=args.port,
-                log_level=args.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)
+    asyncio.run(run_server(args))