Fix model name included in responses (#24663)

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

tests/entrypoints/openai/test_chat.py

@@ -12,7 +12,7 @@ import pytest_asyncio
 import regex as re
 import requests
 import torch
-from openai import BadRequestError, OpenAI
+from openai import BadRequestError
 
 from ...utils import RemoteOpenAIServer
 
@@ -968,59 +968,6 @@ async def test_long_seed(client: openai.AsyncOpenAI):
                 or "less_than_equal" in exc_info.value.message)
 
 
-@pytest.mark.asyncio
-async def test_http_chat_no_model_name_with_curl(server: RemoteOpenAIServer):
-    url = f"http://localhost:{server.port}/v1/chat/completions"
-    headers = {
-        "Content-Type": "application/json",
-    }
-    data = {
-        # model_name is avoided here.
-        "messages": [{
-            "role": "system",
-            "content": "You are a helpful assistant."
-        }, {
-            "role": "user",
-            "content": "what is 1+1?"
-        }],
-        "max_tokens":
-        5
-    }
-
-    response = requests.post(url, headers=headers, json=data)
-    response_data = response.json()
-    print(response_data)
-    assert response_data.get("model") == MODEL_NAME
-    choice = response_data.get("choices")[0]
-    message = choice.get("message")
-    assert message is not None
-    content = message.get("content")
-    assert content is not None
-    assert len(content) > 0
-
-
-@pytest.mark.asyncio
-async def test_http_chat_no_model_name_with_openai(server: RemoteOpenAIServer):
-    openai_api_key = "EMPTY"
-    openai_api_base = f"http://localhost:{server.port}/v1"
-
-    client = OpenAI(
-        api_key=openai_api_key,
-        base_url=openai_api_base,
-    )
-    messages = [
-        {
-            "role": "user",
-            "content": "Hello, vLLM!"
-        },
-    ]
-    response = client.chat.completions.create(
-        model="",  # empty string
-        messages=messages,
-    )
-    assert response.model == MODEL_NAME
-
-
 @pytest.mark.asyncio
 async def test_invocations(server: RemoteOpenAIServer,
                            client: openai.AsyncOpenAI):

tests/entrypoints/openai/test_serving_chat.py

@@ -213,8 +213,12 @@ async def test_gpt_oss_multi_turn_chat(gptoss_client: OpenAI,
 
 
 MODEL_NAME = "openai-community/gpt2"
+MODEL_NAME_SHORT = "gpt2"
 CHAT_TEMPLATE = "Dummy chat template for testing {}"
-BASE_MODEL_PATHS = [BaseModelPath(name=MODEL_NAME, model_path=MODEL_NAME)]
+BASE_MODEL_PATHS = [
+    BaseModelPath(name=MODEL_NAME, model_path=MODEL_NAME),
+    BaseModelPath(name=MODEL_NAME_SHORT, model_path=MODEL_NAME_SHORT)
+]
 
 
 @dataclass
@@ -270,6 +274,42 @@ def test_async_serving_chat_init():
     assert serving_completion.chat_template == CHAT_TEMPLATE
 
 
+@pytest.mark.asyncio
+async def test_serving_chat_returns_correct_model_name():
+    mock_engine = MagicMock(spec=MQLLMEngineClient)
+    mock_engine.get_tokenizer.return_value = get_tokenizer(MODEL_NAME)
+    mock_engine.errored = False
+
+    models = OpenAIServingModels(engine_client=mock_engine,
+                                 base_model_paths=BASE_MODEL_PATHS,
+                                 model_config=MockModelConfig())
+    serving_chat = OpenAIServingChat(mock_engine,
+                                     MockModelConfig(),
+                                     models,
+                                     response_role="assistant",
+                                     chat_template=CHAT_TEMPLATE,
+                                     chat_template_content_format="auto",
+                                     request_logger=None)
+    messages = [{"role": "user", "content": "what is 1+1?"}]
+
+    async def return_model_name(*args):
+        return args[3]
+
+    serving_chat.chat_completion_full_generator = return_model_name
+
+    # Test that full name is returned when short name is requested
+    req = ChatCompletionRequest(model=MODEL_NAME_SHORT, messages=messages)
+    assert await serving_chat.create_chat_completion(req) == MODEL_NAME
+
+    # Test that full name is returned when empty string is specified
+    req = ChatCompletionRequest(model="", messages=messages)
+    assert await serving_chat.create_chat_completion(req) == MODEL_NAME
+
+    # Test that full name is returned when no model is specified
+    req = ChatCompletionRequest(messages=messages)
+    assert await serving_chat.create_chat_completion(req) == MODEL_NAME
+
+
 @pytest.mark.asyncio
 async def test_serving_chat_should_set_correct_max_tokens():
     mock_engine = MagicMock(spec=MQLLMEngineClient)

vllm/entrypoints/openai/serving_chat.py

@@ -186,7 +186,7 @@ class OpenAIServingChat(OpenAIServing):
             lora_request = self._maybe_get_adapters(
                 request, supports_default_mm_loras=True)
 
-            model_name = self._get_model_name(request.model, lora_request)
+            model_name = self.models.model_name(lora_request)
 
             tokenizer = await self.engine_client.get_tokenizer(lora_request)
 

vllm/entrypoints/openai/serving_classification.py

@@ -146,7 +146,7 @@ class ServingClassification(ClassificationMixin):
         request: ClassificationRequest,
         raw_request: Request,
     ) -> Union[ClassificationResponse, ErrorResponse]:
-        model_name = self._get_model_name(request.model)
+        model_name = self.models.model_name()
         request_id = (f"{self.request_id_prefix}-"
                       f"{self._base_request_id(raw_request)}")
 

vllm/entrypoints/openai/serving_completion.py

@@ -232,7 +232,7 @@ class OpenAIServingCompletion(OpenAIServing):
 
         result_generator = merge_async_iterators(*generators)
 
-        model_name = self._get_model_name(request.model, lora_request)
+        model_name = self.models.model_name(lora_request)
         num_prompts = len(engine_prompts)
 
         # Similar to the OpenAI API, when n != best_of, we do not stream the

vllm/entrypoints/openai/serving_embedding.py

@@ -599,7 +599,7 @@ class OpenAIServingEmbedding(EmbeddingMixin):
         See https://platform.openai.com/docs/api-reference/embeddings/create
         for the API specification. This API mimics the OpenAI Embedding API.
         """
-        model_name = self._get_model_name(request.model)
+        model_name = self.models.model_name()
         request_id = (
             f"{self.request_id_prefix}-"
             f"{self._base_request_id(raw_request, request.request_id)}")

vllm/entrypoints/openai/serving_engine.py

@@ -980,17 +980,6 @@ class OpenAIServing:
             return True
         return self.models.is_base_model(model_name)
 
-    def _get_model_name(
-        self,
-        model_name: Optional[str] = None,
-        lora_request: Optional[LoRARequest] = None,
-    ) -> str:
-        if lora_request:
-            return lora_request.lora_name
-        if not model_name:
-            return self.models.base_model_paths[0].name
-        return model_name
-
 
 def clamp_prompt_logprobs(
     prompt_logprobs: Union[PromptLogprobs,

vllm/entrypoints/openai/serving_pooling.py

@@ -91,7 +91,7 @@ class OpenAIServingPooling(OpenAIServing):
         if error_check_ret is not None:
             return error_check_ret
 
-        model_name = self._get_model_name(request.model)
+        model_name = self.models.model_name()
 
         request_id = f"pool-{self._base_request_id(raw_request)}"
         created_time = int(time.time())

vllm/entrypoints/openai/serving_responses.py

@@ -237,7 +237,7 @@ class OpenAIServingResponses(OpenAIServing):
 
         try:
             lora_request = self._maybe_get_adapters(request)
-            model_name = self._get_model_name(request.model, lora_request)
+            model_name = self.models.model_name(lora_request)
             tokenizer = await self.engine_client.get_tokenizer(lora_request)
 
             if self.use_harmony:

vllm/entrypoints/openai/serving_score.py

@@ -353,7 +353,7 @@ class ServingScores(OpenAIServing):
                 final_res_batch,
                 request_id,
                 created_time,
-                self._get_model_name(request.model),
+                self.models.model_name(),
             )
         except asyncio.CancelledError:
             return self.create_error_response("Client disconnected")
@@ -399,7 +399,7 @@ class ServingScores(OpenAIServing):
             return self.request_output_to_rerank_response(
                 final_res_batch,
                 request_id,
-                self._get_model_name(request.model),
+                self.models.model_name(),
                 documents,
                 top_n,
             )