[Frontend] Add --log-level option to api server (#4377)

vllm/entrypoints/api_server.py

@@ -100,6 +100,7 @@ if __name__ == "__main__":
         type=str,
         default=None,
         help="FastAPI root_path when app is behind a path based routing proxy")
+    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)
@@ -110,7 +111,7 @@ if __name__ == "__main__":
     uvicorn.run(app,
                 host=args.host,
                 port=args.port,
-                log_level="debug",
+                log_level=args.log_level,
                 timeout_keep_alive=TIMEOUT_KEEP_ALIVE,
                 ssl_keyfile=args.ssl_keyfile,
                 ssl_certfile=args.ssl_certfile,