Fix code quality issues and add health check endpoints

- Fix duplicate function name bug in controller.py where `worker_api_get_status`
  was defined twice, causing the test_connection endpoint to shadow the worker
  status endpoint
- Fix PEP 8 violation: use `is None` instead of `== None` in model_worker.py
- Fix type comparison: use `isinstance()` instead of `type() ==` in
  openai_api_server.py for better Pythonic style
- Add `/health` endpoint to both controller and openai_api_server for load
  balancer and orchestration system compatibility

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: yurekami

fastchat/serve/controller.py

@@ -346,10 +346,16 @@ async def worker_api_get_status(request: Request):
 
 
 @app.get("/test_connection")
-async def worker_api_get_status(request: Request):
+async def test_connection(request: Request):
     return "success"
 
 
+@app.get("/health")
+async def health_check():
+    """Health check endpoint for load balancers and orchestration systems."""
+    return {"status": "ok"}
+
+
 def create_controller():
     parser = argparse.ArgumentParser()
     parser.add_argument("--host", type=str, default="localhost")

fastchat/serve/model_worker.py

@@ -90,7 +90,7 @@ def __init__(
             debug=debug,
         )
         self.device = device
-        if self.tokenizer.pad_token == None:
+        if self.tokenizer.pad_token is None:
             self.tokenizer.pad_token = self.tokenizer.eos_token
         self.context_len = get_context_length(self.model.config)
         self.generate_stream_func = get_generate_stream_function(self.model, model_path)

fastchat/serve/openai_api_server.py

@@ -304,7 +304,7 @@ async def get_gen_params(
             if msg_role == "system":
                 conv.set_system_message(message["content"])
             elif msg_role == "user":
-                if type(message["content"]) == list:
+                if isinstance(message["content"], list):
                     image_list = [
                         item["image_url"]["url"]
                         for item in message["content"]
@@ -394,6 +394,12 @@ async def get_conv(model_name: str, worker_addr: str):
     return conv_template
 
 
+@app.get("/health")
+async def health_check():
+    """Health check endpoint for load balancers and orchestration systems."""
+    return {"status": "ok"}
+
+
 @app.get("/v1/models", dependencies=[Depends(check_api_key)])
 async def show_available_models():
     controller_address = app_settings.controller_address