[Frontend] Complete OpenAI render delegation

tests/entrypoints/openai/chat_completion/test_chat_error.py

@@ -111,7 +111,7 @@ async def _fake_preprocess_chat(*args, **kwargs):
             [{"prompt_token_ids": [1, 2, 3]}],
         )
 
-    serving_chat.openai_serving_render._preprocess_chat = AsyncMock(
+    serving_chat.openai_serving_render.preprocess_chat = AsyncMock(
         side_effect=_fake_preprocess_chat
     )
     return serving_chat

tests/entrypoints/openai/test_serving_responses.py

@@ -159,6 +159,7 @@ async def serving_responses_instance(self):
         instance = OpenAIServingResponses(
             engine_client=engine_client,
             models=models,
+            openai_serving_render=MagicMock(),
             request_logger=None,
             chat_template=None,
             chat_template_content_format="auto",
@@ -245,6 +246,7 @@ async def serving_responses_instance(self):
         instance = OpenAIServingResponses(
             engine_client=engine_client,
             models=models,
+            openai_serving_render=MagicMock(),
             request_logger=None,
             chat_template=None,
             chat_template_content_format="auto",
@@ -308,6 +310,7 @@ def get_vocab(self):
     serving = OpenAIServingResponses(
         engine_client=engine_client,
         models=models,
+        openai_serving_render=MagicMock(),
         request_logger=None,
         chat_template=None,
         chat_template_content_format="auto",
@@ -607,6 +610,7 @@ def _make_serving_instance_with_reasoning():
     serving = OpenAIServingResponses(
         engine_client=engine_client,
         models=models,
+        openai_serving_render=MagicMock(),
         request_logger=None,
         chat_template=None,
         chat_template_content_format="auto",

vllm/entrypoints/openai/api_server.py

@@ -46,6 +46,7 @@
 from vllm.entrypoints.serve.elastic_ep.middleware import (
     ScalingMiddleware,
 )
+from vllm.entrypoints.serve.render.serving import OpenAIServingRender
 from vllm.entrypoints.serve.tokenize.serving import OpenAIServingTokenization
 from vllm.entrypoints.utils import (
     cli_env_setup,
@@ -365,9 +366,27 @@ async def init_app_state(
         lora_modules=lora_modules,
     )
     await state.openai_serving_models.init_static_loras()
+
+    state.openai_serving_render = OpenAIServingRender(
+        model_config=engine_client.model_config,
+        renderer=engine_client.renderer,
+        io_processor=engine_client.io_processor,
+        model_registry=state.openai_serving_models.registry,
+        request_logger=request_logger,
+        chat_template=resolved_chat_template,
+        chat_template_content_format=args.chat_template_content_format,
+        trust_request_chat_template=args.trust_request_chat_template,
+        enable_auto_tools=args.enable_auto_tool_choice,
+        exclude_tools_when_tool_choice_none=args.exclude_tools_when_tool_choice_none,
+        tool_parser=args.tool_call_parser,
+        default_chat_template_kwargs=args.default_chat_template_kwargs,
+        log_error_stack=args.log_error_stack,
+    )
+
     state.openai_serving_tokenization = OpenAIServingTokenization(
         engine_client,
         state.openai_serving_models,
+        state.openai_serving_render,
         request_logger=request_logger,
         chat_template=resolved_chat_template,
         chat_template_content_format=args.chat_template_content_format,

vllm/entrypoints/openai/engine/serving.py

@@ -4,7 +4,7 @@
 import contextlib
 import json
 import time
-from collections.abc import AsyncGenerator, Callable, Mapping, Sequence
+from collections.abc import AsyncGenerator, Callable, Mapping
 from dataclasses import dataclass, field
 from http import HTTPStatus
 from typing import Any, ClassVar, Generic, Protocol, TypeAlias, TypeVar
@@ -22,9 +22,7 @@
 from vllm.config import ModelConfig
 from vllm.engine.protocol import EngineClient
 from vllm.entrypoints.chat_utils import (
-    ChatCompletionMessageParam,
     ChatTemplateContentFormatOption,
-    ConversationMessage,
 )
 from vllm.entrypoints.logger import RequestLogger
 from vllm.entrypoints.openai.chat_completion.protocol import (
@@ -43,19 +41,9 @@
     GenerationError,
 )
 from vllm.entrypoints.openai.models.serving import OpenAIServingModels
-from vllm.entrypoints.openai.responses.context import (
-    ConversationContext,
-    HarmonyContext,
-    ParsableContext,
-    StreamingHarmonyContext,
-)
 from vllm.entrypoints.openai.responses.protocol import (
-    ResponseInputOutputItem,
     ResponsesRequest,
 )
-from vllm.entrypoints.openai.responses.utils import (
-    construct_input_messages,
-)
 from vllm.entrypoints.openai.speech_to_text.protocol import (
     TranscriptionRequest,
     TranscriptionResponse,
@@ -82,26 +70,22 @@
     TokenizeCompletionRequest,
     TokenizeResponse,
 )
-from vllm.entrypoints.utils import create_error_response, get_max_tokens
+from vllm.entrypoints.utils import create_error_response
 from vllm.exceptions import VLLMValidationError
 from vllm.inputs.data import (
     ProcessorInputs,
     PromptType,
-    SingletonPrompt,
     TokensPrompt,
-    token_inputs,
 )
 from vllm.logger import init_logger
 from vllm.logprobs import Logprob, PromptLogprobs
 from vllm.lora.request import LoRARequest
 from vllm.outputs import CompletionOutput, PoolingRequestOutput, RequestOutput
 from vllm.pooling_params import PoolingParams
-from vllm.renderers import ChatParams, TokenizeParams, merge_kwargs
+from vllm.renderers import ChatParams, TokenizeParams
 from vllm.renderers.inputs.preprocess import (
     extract_prompt_components,
     extract_prompt_len,
-    parse_model_prompt,
-    prompt_to_seq,
 )
 from vllm.sampling_params import BeamSearchParams, SamplingParams
 from vllm.tokenizers import TokenizerLike
@@ -116,7 +100,6 @@
     collect_from_async_generator,
     merge_async_iterators,
 )
-from vllm.utils.mistral import is_mistral_tokenizer
 
 logger = init_logger(__name__)
 
@@ -823,109 +806,6 @@ def _prepare_extra_chat_template_kwargs(
         # Apply server defaults first, then request kwargs override.
         return default_chat_template_kwargs | request_chat_template_kwargs
 
-    async def _preprocess_completion(
-        self,
-        request: RendererRequest,
-        prompt_input: str | list[str] | list[int] | list[list[int]] | None,
-        prompt_embeds: bytes | list[bytes] | None,
-    ) -> list[ProcessorInputs]:
-        prompts = list[SingletonPrompt | bytes]()
-        if prompt_embeds is not None:  # embeds take higher priority
-            prompts.extend(prompt_to_seq(prompt_embeds))
-        if prompt_input is not None:
-            prompts.extend(prompt_to_seq(prompt_input))
-
-        return await self._preprocess_cmpl(request, prompts)
-
-    async def _preprocess_cmpl(
-        self,
-        request: RendererRequest,
-        prompts: Sequence[PromptType | bytes],
-    ) -> list[ProcessorInputs]:
-        renderer = self.renderer
-        model_config = self.model_config
-
-        parsed_prompts = [
-            (
-                prompt
-                if isinstance(prompt, bytes)
-                else parse_model_prompt(model_config, prompt)
-            )
-            for prompt in prompts
-        ]
-        tok_params = request.build_tok_params(model_config)
-
-        return await renderer.render_cmpl_async(
-            parsed_prompts,
-            tok_params,
-            prompt_extras={
-                k: v
-                for k in ("mm_processor_kwargs", "cache_salt")
-                if (v := getattr(request, k, None)) is not None
-            },
-        )
-
-    async def _preprocess_chat(
-        self,
-        request: RendererChatRequest,
-        messages: list[ChatCompletionMessageParam],
-        default_template: str | None,
-        default_template_content_format: ChatTemplateContentFormatOption,
-        default_template_kwargs: dict[str, Any] | None,
-        tool_dicts: list[dict[str, Any]] | None = None,
-        tool_parser: Callable[[TokenizerLike], ToolParser] | None = None,
-    ) -> tuple[list[ConversationMessage], list[ProcessorInputs]]:
-        renderer = self.renderer
-
-        default_template_kwargs = merge_kwargs(
-            default_template_kwargs,
-            dict(
-                tools=tool_dicts,
-                tokenize=is_mistral_tokenizer(renderer.tokenizer),
-            ),
-        )
-
-        mm_config = self.model_config.multimodal_config
-
-        tok_params = request.build_tok_params(self.model_config)
-        chat_params = request.build_chat_params(
-            default_template, default_template_content_format
-        ).with_defaults(
-            default_template_kwargs,
-            default_media_io_kwargs=(mm_config.media_io_kwargs if mm_config else None),
-            default_mm_processor_kwargs=getattr(request, "mm_processor_kwargs", None),
-        )
-
-        (conversation,), (engine_prompt,) = await renderer.render_chat_async(
-            [messages],
-            chat_params,
-            tok_params,
-            prompt_extras={
-                k: v
-                for k in ("mm_processor_kwargs", "cache_salt")
-                if (v := getattr(request, k, None)) is not None
-            },
-        )
-
-        # tool parsing is done only if a tool_parser has been set and if
-        # tool_choice is not "none" (if tool_choice is "none" but a tool_parser
-        # is set, we want to prevent parsing a tool_call hallucinated by the LLM
-        if tool_parser is not None:
-            tool_choice = getattr(request, "tool_choice", "none")
-            if tool_choice != "none":
-                if not isinstance(request, ChatCompletionRequest | ResponsesRequest):
-                    msg = (
-                        "Tool usage is only supported for Chat Completions API "
-                        "or Responses API requests."
-                    )
-                    raise NotImplementedError(msg)
-
-                # TODO: Update adjust_request to accept ResponsesRequest
-                tokenizer = renderer.get_tokenizer()
-                request = tool_parser(tokenizer).adjust_request(request=request)  # type: ignore[arg-type]
-
-        return conversation, [engine_prompt]
-
     def _extract_prompt_components(self, prompt: PromptType | ProcessorInputs):
         return extract_prompt_components(self.model_config, prompt)
 
@@ -935,109 +815,6 @@ def _extract_prompt_text(self, prompt: ProcessorInputs):
     def _extract_prompt_len(self, prompt: ProcessorInputs):
         return extract_prompt_len(self.model_config, prompt)
 
-    async def _render_next_turn(
-        self,
-        request: ResponsesRequest,
-        messages: list[ResponseInputOutputItem],
-        tool_dicts: list[dict[str, Any]] | None,
-        tool_parser: Callable[[TokenizerLike], ToolParser] | None,
-        chat_template: str | None,
-        chat_template_content_format: ChatTemplateContentFormatOption,
-    ):
-        new_messages = construct_input_messages(
-            request_input=messages,
-        )
-
-        _, engine_prompts = await self._preprocess_chat(
-            request,
-            new_messages,
-            default_template=chat_template,
-            default_template_content_format=chat_template_content_format,
-            default_template_kwargs=None,
-            tool_dicts=tool_dicts,
-            tool_parser=tool_parser,
-        )
-        return engine_prompts
-
-    async def _generate_with_builtin_tools(
-        self,
-        request_id: str,
-        engine_prompt: ProcessorInputs,
-        sampling_params: SamplingParams,
-        context: ConversationContext,
-        lora_request: LoRARequest | None = None,
-        priority: int = 0,
-        trace_headers: Mapping[str, str] | None = None,
-    ):
-        max_model_len = self.model_config.max_model_len
-
-        orig_priority = priority
-        sub_request = 0
-        while True:
-            # Ensure that each sub-request has a unique request id.
-            sub_request_id = f"{request_id}_{sub_request}"
-
-            self._log_inputs(
-                sub_request_id,
-                engine_prompt,
-                params=sampling_params,
-                lora_request=lora_request,
-            )
-
-            generator = self.engine_client.generate(
-                engine_prompt,
-                sampling_params,
-                sub_request_id,
-                lora_request=lora_request,
-                trace_headers=trace_headers,
-                priority=priority,
-            )
-
-            async for res in generator:
-                context.append_output(res)
-                # NOTE(woosuk): The stop condition is handled by the engine.
-                yield context
-
-            if not context.need_builtin_tool_call():
-                # The model did not ask for a tool call, so we're done.
-                break
-
-            # Call the tool and update the context with the result.
-            tool_output = await context.call_tool()
-            context.append_tool_output(tool_output)
-
-            # TODO: uncomment this and enable tool output streaming
-            # yield context
-
-            # Create inputs for the next turn.
-            # Render the next prompt token ids and update sampling_params.
-            if isinstance(context, (HarmonyContext, StreamingHarmonyContext)):
-                token_ids = context.render_for_completion()
-                engine_prompt = token_inputs(token_ids)
-
-                sampling_params.max_tokens = max_model_len - len(token_ids)
-            elif isinstance(context, ParsableContext):
-                (engine_prompt,) = await self._render_next_turn(
-                    context.request,
-                    context.parser.response_messages,
-                    context.tool_dicts,
-                    context.tool_parser_cls,
-                    context.chat_template,
-                    context.chat_template_content_format,
-                )
-
-                sampling_params.max_tokens = get_max_tokens(
-                    max_model_len,
-                    context.request.max_output_tokens,
-                    self._extract_prompt_len(engine_prompt),
-                    self.default_sampling_params,  # type: ignore
-                    self.override_max_tokens,  # type: ignore
-                )
-
-            # OPTIMIZATION
-            priority = orig_priority - 1
-            sub_request += 1
-
     def _log_inputs(
         self,
         request_id: str,