[Bug fix] Add /model_info endpoint to mini_lb (sgl-project#14535)

Author: alisonshao

sgl-model-gateway/bindings/python/sglang_router/mini_lb.py

@@ -341,16 +341,15 @@ async def get_server_info():
         }
 
 
-@app.get("/get_model_info")
-async def get_model_info():
+async def _get_model_info_impl():
     if not lb or not lb.prefill_urls:
         raise HTTPException(
             status_code=HTTPStatus.SERVICE_UNAVAILABLE,
             detail="There is no server registered",
         )
 
     target_server_url = lb.prefill_urls[0]
-    endpoint_url = f"{target_server_url}/get_model_info"
+    endpoint_url = f"{target_server_url}/model_info"
 
     async with aiohttp.ClientSession() as session:
         try:
@@ -375,6 +374,16 @@ async def get_model_info():
             )
 
 
+@app.get("/model_info")
+async def model_info():
+    return await _get_model_info_impl()
+
+
+@app.get("/get_model_info")
+async def get_model_info():
+    return await _get_model_info_impl()
+
+
 @app.post("/generate")
 async def handle_generate_request(request_data: dict):
     prefill_server, bootstrap_port, decode_server = lb.select_pair()