[feat] add disable_chat_template in chat api as a substitute for previous raw_request (#3020)

* [feat] add disable_chat_template in chat api as a substitute for previous raw_request

* [fix] pre-commit code check

fastdeploy/engine/request.py

@@ -60,6 +60,7 @@ class Request:
         preprocess_end_time: Optional[float] = None,
         multimodal_inputs: Optional[dict] = None,
         multimodal_data: Optional[dict] = None,
+        disable_chat_template: bool = False,
         disaggregate_info: Optional[dict] = None,
         draft_token_ids: Optional[list[int]] = None,
         guided_json: Optional[Any] = None,
@@ -87,6 +88,7 @@ class Request:
         self.arrival_time = arrival_time
         self.preprocess_start_time = preprocess_start_time
         self.preprocess_end_time = preprocess_end_time
+        self.disable_chat_template = disable_chat_template
         self.disaggregate_info = disaggregate_info
 
         # speculative method in disaggregate-mode
@@ -136,6 +138,7 @@ class Request:
             preprocess_end_time=d.get("preprocess_end_time"),
             multimodal_inputs=d.get("multimodal_inputs"),
             multimodal_data=d.get("multimodal_data"),
+            disable_chat_template=d.get("disable_chat_template"),
             disaggregate_info=d.get("disaggregate_info"),
             draft_token_ids=d.get("draft_token_ids"),
             guided_json=d.get("guided_json", None),
@@ -180,6 +183,7 @@ class Request:
             "preprocess_end_time": self.preprocess_end_time,
             "multimodal_inputs": self.multimodal_inputs,
             "multimodal_data": self.multimodal_data,
+            "disable_chat_template": self.disable_chat_template,
             "disaggregate_info": self.disaggregate_info,
             "draft_token_ids": self.draft_token_ids,
             "enable_thinking": self.enable_thinking,

fastdeploy/entrypoints/openai/protocol.py

@@ -483,6 +483,7 @@ class ChatCompletionRequest(BaseModel):
     extra_body: Optional[dict] = None
     return_token_ids: Optional[bool] = False
     prompt_token_ids: Optional[List[int]] = None
+    disable_chat_template: Optional[bool] = False
 
     response_format: Optional[AnyResponseFormat] = None
     guided_json: Optional[Union[str, dict, BaseModel]] = None
@@ -531,6 +532,11 @@ class ChatCompletionRequest(BaseModel):
         else:
             assert len(self.messages) > 0
 
+        # If disable_chat_template is set, then the first message in messages will be used as the prompt.
+        if self.disable_chat_template:
+            req_dict["prompt"] = req_dict["messages"][0]["content"]
+            del req_dict["messages"]
+
         guided_json_object = None
         if self.response_format is not None:
             if self.response_format.type == "json_object":

test/ci_use/EB_Lite/test_EB_Lite_serving.py

@@ -662,3 +662,37 @@ def test_streaming_completion_with_prompt_token_ids(openai_client, capsys):
         else:
             assert hasattr(chunk.usage, "prompt_tokens")
             assert chunk.usage.prompt_tokens == 9
+
+
+def test_non_streaming_chat_completion_disable_chat_template(openai_client, capsys):
+    """
+    Test disable_chat_template option in chat functionality with the local service.
+    """
+    enabled_response = openai_client.chat.completions.create(
+        model="default",
+        messages=[{"role": "user", "content": "Hello, how are you?"}],
+        max_tokens=10,
+        temperature=0.0,
+        top_p=0,
+        extra_body={"disable_chat_template": False},
+        stream=False,
+    )
+    assert hasattr(enabled_response, "choices")
+    assert len(enabled_response.choices) > 0
+
+    # from fastdeploy.input.ernie_tokenizer import ErnieBotTokenizer
+    # tokenizer = ErnieBotTokenizer.from_pretrained("PaddlePaddle/ERNIE-4.5-0.3B-Paddle", trust_remote_code=True)
+    # prompt = tokenizer.apply_chat_template([{"role": "user", "content": "Hello, how are you?"}], tokenize=False)
+    prompt = "<|begin_of_sentence|>User: Hello, how are you?\nAssistant: "
+    disabled_response = openai_client.chat.completions.create(
+        model="default",
+        messages=[{"role": "user", "content": prompt}],
+        max_tokens=10,
+        temperature=0,
+        top_p=0,
+        extra_body={"disable_chat_template": True},
+        stream=False,
+    )
+    assert hasattr(disabled_response, "choices")
+    assert len(disabled_response.choices) > 0
+    assert enabled_response.choices[0].message.content == disabled_response.choices[0].message.content