Revert "add best_of and use_beam_search for completions interface" (#2401)

Author: merrymercy

fastchat/protocol/api_protocol.py

@@ -150,7 +150,7 @@ class CompletionResponse(BaseModel):
     created: int = Field(default_factory=lambda: int(time.time()))
     model: str
     choices: List[CompletionResponseChoice]
-    usage: Union[UsageInfo, List[UsageInfo]]
+    usage: UsageInfo
 
 
 class CompletionResponseStreamChoice(BaseModel):

fastchat/protocol/openai_api_protocol.py

@@ -151,13 +151,11 @@ class CompletionRequest(BaseModel):
     presence_penalty: Optional[float] = 0.0
     frequency_penalty: Optional[float] = 0.0
     user: Optional[str] = None
-    use_beam_search: Optional[bool] = False
-    best_of: Optional[int] = None
 
 
 class CompletionResponseChoice(BaseModel):
     index: int
-    text: Union[str, List[str]]
+    text: str
     logprobs: Optional[int] = None
     finish_reason: Optional[Literal["stop", "length"]] = None
 

fastchat/serve/openai_api_server.py

@@ -241,9 +241,6 @@ async def get_gen_params(
     max_tokens: Optional[int],
     echo: Optional[bool],
     stop: Optional[Union[str, List[str]]],
-    best_of: Optional[int] = None,
-    n: Optional[int] = 1,
-    use_beam_search: Optional[bool] = None,
 ) -> Dict[str, Any]:
     conv = await get_conv(model_name, worker_addr)
     conv = Conversation(
@@ -290,11 +287,6 @@ async def get_gen_params(
         "stop_token_ids": conv.stop_token_ids,
     }
 
-    if best_of is not None:
-        gen_params.update({"n": n, "best_of": best_of})
-    if use_beam_search is not None:
-        gen_params.update({"use_beam_search": use_beam_search})
-
     new_stop = set()
     _add_to_set(stop, new_stop)
     _add_to_set(conv.stop_str, new_stop)
@@ -502,18 +494,12 @@ async def create_completion(request: CompletionRequest):
                 max_tokens=request.max_tokens,
                 echo=request.echo,
                 stop=request.stop,
-                best_of=request.best_of,
-                n=request.n,
-                use_beam_search=request.use_beam_search,
             )
             for i in range(request.n):
                 content = asyncio.create_task(
                     generate_completion(gen_params, worker_addr)
                 )
                 text_completions.append(content)
-                # when use with best_of, only need send one request
-                if request.best_of:
-                    break
 
         try:
             all_tasks = await asyncio.gather(*text_completions)
@@ -533,18 +519,9 @@ async def create_completion(request: CompletionRequest):
                     finish_reason=content.get("finish_reason", "stop"),
                 )
             )
-            idx = 0
-            while True:
-                info = content["usage"]
-                if isinstance(info, list):
-                    info = info[idx]
-
-                task_usage = UsageInfo.parse_obj(info)
-
-                for usage_key, usage_value in task_usage.dict().items():
-                    setattr(usage, usage_key, getattr(usage, usage_key) + usage_value)
-                idx += 1
-                break
+            task_usage = UsageInfo.parse_obj(content["usage"])
+            for usage_key, usage_value in task_usage.dict().items():
+                setattr(usage, usage_key, getattr(usage, usage_key) + usage_value)
 
         return CompletionResponse(
             model=request.model, choices=choices, usage=UsageInfo.parse_obj(usage)

fastchat/serve/vllm_worker.py

@@ -18,7 +18,6 @@
 from vllm.sampling_params import SamplingParams
 from vllm.utils import random_uuid
 
-from fastchat.constants import ErrorCode, SERVER_ERROR_MSG
 from fastchat.serve.model_worker import (
     BaseModelWorker,
     logger,
@@ -75,9 +74,6 @@ async def generate_stream(self, params):
         if self.tokenizer.eos_token_id is not None:
             stop_token_ids.append(self.tokenizer.eos_token_id)
         echo = params.get("echo", True)
-        use_beam_search = params.get("use_beam_search", False)
-        best_of = params.get("best_of", None)
-        n = params.get("n", 1)
 
         # Handle stop_str
         stop = set()
@@ -94,51 +90,27 @@ async def generate_stream(self, params):
         top_p = max(top_p, 1e-5)
         if temperature <= 1e-5:
             top_p = 1.0
-        try:
-            sampling_params = SamplingParams(
-                n=n,
-                temperature=temperature,
-                top_p=top_p,
-                use_beam_search=use_beam_search,
-                stop=list(stop),
-                max_tokens=max_new_tokens,
-                best_of=best_of,
-            )
-
-            results_generator = engine.generate(context, sampling_params, request_id)
-
-            async for request_output in results_generator:
-                prompt = request_output.prompt
-                prompt_tokens = len(request_output.prompt_token_ids)
-                output_usage = []
-                for out in request_output.outputs:
-                    completion_tokens = len(out.token_ids)
-                    total_tokens = prompt_tokens + completion_tokens
-                    output_usage.append(
-                        {
-                            "prompt_tokens": prompt_tokens,
-                            "completion_tokens": completion_tokens,
-                            "total_tokens": total_tokens,
-                        }
-                    )
-
-                if echo:
-                    text_outputs = [
-                        prompt + output.text for output in request_output.outputs
-                    ]
-                else:
-                    text_outputs = [output.text for output in request_output.outputs]
-
-                if sampling_params.best_of is None:
-                    text_outputs = [" ".join(text_outputs)]
-                ret = {"text": text_outputs, "error_code": 0, "usage": output_usage}
-                yield (json.dumps(ret) + "\0").encode()
-        except (ValueError, RuntimeError) as e:
-            ret = {
-                "text": f"{e}",
-                "error_code": ErrorCode.PARAM_OUT_OF_RANGE,
-                "usage": {},
-            }
+        sampling_params = SamplingParams(
+            n=1,
+            temperature=temperature,
+            top_p=top_p,
+            use_beam_search=False,
+            stop=list(stop),
+            max_tokens=max_new_tokens,
+        )
+        results_generator = engine.generate(context, sampling_params, request_id)
+
+        async for request_output in results_generator:
+            prompt = request_output.prompt
+            if echo:
+                text_outputs = [
+                    prompt + output.text for output in request_output.outputs
+                ]
+            else:
+                text_outputs = [output.text for output in request_output.outputs]
+            text_outputs = " ".join(text_outputs)
+            # Note: usage is not supported yet
+            ret = {"text": text_outputs, "error_code": 0, "usage": {}}
             yield (json.dumps(ret) + "\0").encode()
 
     async def generate(self, params):