fix: fixes for pr review comments

* remove unused import
* fix FastAPI app route accumulation
* remove duplicate error handler
* add types for response_model

Signed-off-by: Mark Sturdevant <mark.sturdevant@ibm.com>

Author: markstur

cli/serve/app.py

@@ -8,7 +8,7 @@
 
 import typer
 import uvicorn
-from fastapi import FastAPI, Request
+from fastapi import FastAPI
 from fastapi.responses import JSONResponse
 
 from .models import (
@@ -79,13 +79,6 @@ async def endpoint(request: ChatCompletionRequest):
                 ],
                 object="chat.completion",  # type: ignore
             )  # type: ignore
-        except AttributeError as e:
-            # Handle missing 'value' attribute or other attribute errors
-            return create_openai_error_response(
-                status_code=500,
-                message=f"Internal server error: {e!s}",
-                error_type="server_error",
-            )
         except ValueError as e:
             # Handle validation errors or invalid input
             return create_openai_error_response(
@@ -94,7 +87,7 @@ async def endpoint(request: ChatCompletionRequest):
                 error_type="invalid_request_error",
             )
         except Exception as e:
-            # Catch-all for any other unexpected errors
+            # Catch-all for any unexpected errors (including AttributeError)
             return create_openai_error_response(
                 status_code=500,
                 message=f"Internal server error: {e!s}",
@@ -121,7 +114,7 @@ def serve(
         route_path,
         make_chat_endpoint(module),
         methods=["POST"],
-        response_model=None,  # Allow both ChatCompletion and error responses
+        response_model=ChatCompletion | OpenAIErrorResponse,
     )
     typer.echo(f"Serving {route_path} at http://{host}:{port}")
     uvicorn.run(app, host=host, port=port)

test/cli/test_serve_errors.py

@@ -3,9 +3,10 @@
 from unittest.mock import Mock
 
 import pytest
+from fastapi import FastAPI
 from fastapi.testclient import TestClient
 
-from cli.serve.app import app, make_chat_endpoint
+from cli.serve.app import make_chat_endpoint
 from cli.serve.models import ChatCompletionRequest, ChatMessage
 
 
@@ -61,11 +62,10 @@ def sample_request():
 @pytest.mark.unit
 def test_successful_completion(mock_module_success, sample_request):
     """Test successful chat completion."""
+    app = FastAPI()
     endpoint = make_chat_endpoint(mock_module_success)
-    client = TestClient(app)
-
-    # Add the endpoint to the app
     app.add_api_route("/test/completions", endpoint, methods=["POST"])
+    client = TestClient(app)
 
     response = client.post("/test/completions", json=sample_request.model_dump())
 
@@ -80,10 +80,10 @@ def test_successful_completion(mock_module_success, sample_request):
 @pytest.mark.unit
 def test_attribute_error_handling(mock_module_attribute_error, sample_request):
     """Test handling of AttributeError (e.g., missing 'value' attribute)."""
+    app = FastAPI()
     endpoint = make_chat_endpoint(mock_module_attribute_error)
-    client = TestClient(app)
-
     app.add_api_route("/test/attribute-error", endpoint, methods=["POST"])
+    client = TestClient(app)
 
     response = client.post("/test/attribute-error", json=sample_request.model_dump())
 
@@ -97,10 +97,10 @@ def test_attribute_error_handling(mock_module_attribute_error, sample_request):
 @pytest.mark.unit
 def test_value_error_handling(mock_module_value_error, sample_request):
     """Test handling of ValueError (validation errors)."""
+    app = FastAPI()
     endpoint = make_chat_endpoint(mock_module_value_error)
-    client = TestClient(app)
-
     app.add_api_route("/test/value-error", endpoint, methods=["POST"])
+    client = TestClient(app)
 
     response = client.post("/test/value-error", json=sample_request.model_dump())
 
@@ -115,10 +115,10 @@ def test_value_error_handling(mock_module_value_error, sample_request):
 @pytest.mark.unit
 def test_generic_error_handling(mock_module_generic_error, sample_request):
     """Test handling of generic exceptions."""
+    app = FastAPI()
     endpoint = make_chat_endpoint(mock_module_generic_error)
-    client = TestClient(app)
-
     app.add_api_route("/test/generic-error", endpoint, methods=["POST"])
+    client = TestClient(app)
 
     response = client.post("/test/generic-error", json=sample_request.model_dump())