import asyncio import base64 import json import time import uuid from collections.abc import AsyncGenerator, AsyncIterator, Callable, Sequence from datetime import datetime, timedelta, timezone from io import BytesIO from typing import TYPE_CHECKING, Any, Final, Optional, cast import jinja2 import torch from fastapi import Request from PIL import Image from pydantic import TypeAdapter from vllm.renderers import RendererLike from vllm_omni.entrypoints.async_omni import AsyncOmni from vllm_omni.inputs.data import OmniDiffusionSamplingParams, OmniTextPrompt try: import soundfile except ImportError: soundfile = None from openai.types.chat.chat_completion_audio import ChatCompletionAudio as OpenAIChatCompletionAudio from vllm.entrypoints.chat_utils import ( ChatCompletionMessageParam, ChatTemplateContentFormatOption, ConversationMessage, get_history_tool_calls_cnt, make_tool_call_id, ) from vllm.entrypoints.openai.chat_completion.protocol import ( ChatCompletionNamedToolChoiceParam, ChatCompletionRequest, ChatCompletionResponse, ChatCompletionResponseChoice, ChatCompletionResponseStreamChoice, ChatCompletionStreamResponse, ChatMessage, ) from vllm.entrypoints.openai.chat_completion.serving import OpenAIServingChat from vllm.entrypoints.openai.engine.protocol import ( DeltaFunctionCall, DeltaMessage, DeltaToolCall, ErrorInfo, ErrorResponse, FunctionCall, FunctionDefinition, PromptTokenUsageInfo, RequestResponseMetadata, ToolCall, UsageInfo, ) from vllm.entrypoints.openai.engine.serving import ChatLikeRequest, clamp_prompt_logprobs from vllm.entrypoints.openai.parser.harmony_utils import ( get_streamable_parser_for_assistant, parse_chat_output, ) from vllm.entrypoints.openai.responses.protocol import ResponsesRequest from vllm.entrypoints.openai.utils import maybe_filter_parallel_tool_calls from vllm.entrypoints.utils import should_include_usage from vllm.inputs.data import PromptType, TokensPrompt from vllm.logger import init_logger from vllm.outputs import RequestOutput from vllm.renderers.hf import ( resolve_chat_template_content_format, ) from vllm.renderers.hf import ( safe_apply_chat_template as apply_hf_chat_template, ) from vllm.renderers.mistral import ( safe_apply_chat_template as apply_mistral_chat_template, ) from vllm.sampling_params import SamplingParams from vllm.tokenizers import TokenizerLike from vllm.tokenizers.mistral import ( MistralTokenizer, maybe_serialize_tool_calls, truncate_tool_call_ids, validate_request_params, ) from vllm.tool_parsers import ToolParser from vllm.tool_parsers.mistral_tool_parser import MistralToolCall from vllm.transformers_utils.tokenizer import AnyTokenizer from vllm.utils.collection_utils import as_list, is_list_of from vllm_omni.entrypoints.chat_utils import parse_chat_messages_futures from vllm_omni.entrypoints.openai.audio_utils_mixin import AudioMixin from vllm_omni.entrypoints.openai.protocol import OmniChatCompletionStreamResponse from vllm_omni.entrypoints.openai.protocol.audio import AudioResponse, CreateAudio from vllm_omni.lora.request import LoRARequest from vllm_omni.lora.utils import stable_lora_int_id from vllm_omni.outputs import OmniRequestOutput if TYPE_CHECKING: from vllm_omni.entrypoints.async_omni_diffusion import AsyncOmniDiffusion logger = init_logger(__name__) class OmniOpenAIServingChat(OpenAIServingChat, AudioMixin): """OpenAI-compatible chat serving for both LLM and Diffusion models. This class extends OpenAIServingChat to support: - Standard LLM chat completions - Diffusion model image generation via chat interface For diffusion mode, use the `for_diffusion` class method to create an instance. """ # Diffusion mode attributes _diffusion_mode: bool = False _diffusion_engine: Optional["AsyncOmniDiffusion"] = None _diffusion_model_name: str = "" @classmethod def for_diffusion( cls, diffusion_engine: "AsyncOmniDiffusion", model_name: str, ) -> "OmniOpenAIServingChat": """Create a chat serving instance for diffusion models. Args: diffusion_engine: The async diffusion engine model_name: Name of the model being served Returns: OmniOpenAIServingChat instance configured for diffusion mode Note: Request-level parameters (num_inference_steps, guidance_scale, seed, height, width, num_frames, fps, etc.) are passed per-request via the API. """ instance = cls.__new__(cls) instance._diffusion_mode = True instance._diffusion_engine = diffusion_engine instance._diffusion_model_name = model_name return instance async def create_chat_completion( self, request: ChatCompletionRequest, raw_request: Request | None = None, ) -> AsyncGenerator[str, None] | ChatCompletionResponse | ErrorResponse: """ Chat Completion API similar to OpenAI's API. See https://platform.openai.com/docs/api-reference/chat/create for the API specification. This API mimics the OpenAI Chat Completion API. For diffusion models, this generates images and returns them in a chat completion response format. """ # Handle diffusion mode if self._diffusion_mode: return await self._create_diffusion_chat_completion(request, raw_request) error_check_ret = await self._check_model(request) if error_check_ret is not None: logger.error("Error with model %s", error_check_ret) return error_check_ret # If the engine is dead, raise the engine's DEAD_ERROR. # This is required for the streaming case, where we return a # success status before we actually start generating text :). if self.engine_client.errored: raise self.engine_client.dead_error try: lora_request = self._maybe_get_adapters(request, supports_default_mm_loras=True) model_name = self.models.model_name(lora_request) renderer = self.renderer tokenizer = renderer.get_tokenizer() if tokenizer is None: tokenizer = await self.engine_client.get_tokenizer() tool_parser = self.tool_parser if isinstance(tokenizer, MistralTokenizer): # because of issues with pydantic we need to potentially # re-serialize the tool_calls field of the request # for more info: see comment in `maybe_serialize_tool_calls` maybe_serialize_tool_calls(request) truncate_tool_call_ids(request) validate_request_params(request) # Check if tool parsing is unavailable (common condition) tool_parsing_unavailable = ( tool_parser is None and not isinstance(tokenizer, MistralTokenizer) and not self.use_harmony ) # Validate tool_choice when tool parsing is required but unavailable if tool_parsing_unavailable and request.tool_choice not in ( None, "none", ): if request.tool_choice == "auto" and not self.enable_auto_tools: # for hf tokenizers, "auto" tools requires # --enable-auto-tool-choice and --tool-call-parser return self.create_error_response( '"auto" tool choice requires --enable-auto-tool-choice and --tool-call-parser to be set' ) elif request.tool_choice != "auto": # "required" or named tool requires tool parser return self.create_error_response( f'tool_choice="{request.tool_choice}" requires --tool-call-parser to be set' ) if request.tools is None or (request.tool_choice == "none" and self.exclude_tools_when_tool_choice_none): tool_dicts = None else: tool_dicts = [tool.model_dump() for tool in request.tools] if not self.use_harmony: error_check_ret = self._validate_chat_template( request_chat_template=request.chat_template, chat_template_kwargs=request.chat_template_kwargs, trust_request_chat_template=self.trust_request_chat_template, ) if error_check_ret is not None: return error_check_ret chat_template_kwargs = request.chat_template_kwargs or {} chat_template_kwargs.update(reasoning_effort=request.reasoning_effort) ( conversation, request_prompts, engine_prompts, ) = await self._preprocess_chat( request, renderer, request.messages, chat_template=request.chat_template or self.chat_template, chat_template_content_format=self.chat_template_content_format, add_generation_prompt=request.add_generation_prompt, continue_final_message=request.continue_final_message, tool_dicts=tool_dicts, documents=getattr(request, "documents", None), chat_template_kwargs=chat_template_kwargs, default_chat_template_kwargs=self.default_chat_template_kwargs, tool_parser=tool_parser, add_special_tokens=request.add_special_tokens, ) else: should_include_tools = tool_dicts is not None conversation, engine_prompts = self._make_request_with_harmony(request, should_include_tools) request_prompts = [engine_prompt.get("prompt_token_ids", []) for engine_prompt in engine_prompts] except (ValueError, TypeError, RuntimeError, jinja2.TemplateError) as e: logger.exception("Error in preprocessing prompt inputs") return self.create_error_response(f"{e} {e.__cause__}") request_id = f"chatcmpl-{self._base_request_id(raw_request, request.request_id)}" request_metadata = RequestResponseMetadata(request_id=request_id) if raw_request: raw_request.state.request_metadata = request_metadata output_modalities = getattr(request, "modalities", self.engine_client.output_modalities) request.modalities = ( output_modalities if output_modalities is not None else self.engine_client.output_modalities ) # Schedule the request and get the result generator. generators: list[AsyncGenerator[RequestOutput, None]] = [] try: for i, engine_prompt in enumerate(engine_prompts): if hasattr(request, "sampling_params_list"): sampling_params_list = self._to_sampling_params_list(request.sampling_params_list) else: # Use standard OpenAI API parameters for comprehension stage sampling_params_list = self._build_sampling_params_list_from_request(request) self._log_inputs( request_id, request_prompts[i], params_list=sampling_params_list, lora_request=lora_request, ) generator = self.engine_client.generate( prompt=engine_prompt, request_id=request_id, sampling_params_list=sampling_params_list, output_modalities=output_modalities, ) generators.append(generator) except ValueError as e: return self.create_error_response(e) assert len(generators) == 1 (result_generator,) = generators # Streaming response if request.stream: return self.chat_completion_stream_generator( request, result_generator, request_id, model_name, conversation, tokenizer, request_metadata, ) try: return await self.chat_completion_full_generator( request, result_generator, request_id, model_name, conversation, tokenizer, request_metadata, ) except ValueError as e: return self.create_error_response(e) async def _preprocess_chat( self, request: ChatLikeRequest | ResponsesRequest, renderer: RendererLike, messages: list[ChatCompletionMessageParam], chat_template: str | None, chat_template_content_format: ChatTemplateContentFormatOption, add_generation_prompt: bool = True, continue_final_message: bool = False, tool_dicts: list[dict[str, Any]] | None = None, documents: list[dict[str, str]] | None = None, chat_template_kwargs: dict[str, Any] | None = None, default_chat_template_kwargs: dict[str, Any] | None = None, tool_parser: Callable[[TokenizerLike], ToolParser] | None = None, add_special_tokens: bool = False, ) -> tuple[ list[ConversationMessage], Sequence[PromptType], list[TokensPrompt], ]: model_config = self.model_config tokenizer = renderer.get_tokenizer() if renderer is not None else None if tokenizer is None or isinstance(tokenizer, MistralTokenizer): resolved_content_format = ( chat_template_content_format if chat_template_content_format != "auto" else "string" ) else: resolved_content_format = resolve_chat_template_content_format( chat_template, tool_dicts, chat_template_content_format, tokenizer, model_config=model_config, ) # OMNI: Updated for vLLM v0.15.0 API - resolve_items() returns (mm_data, mm_uuids) tuple conversation, mm_future = parse_chat_messages_futures( messages, model_config, content_format=resolved_content_format, mm_processor_kwargs=getattr(request, "mm_processor_kwargs", None), ) # Merge default_chat_template_kwargs with request-provided kwargs # Request kwargs take precedence over defaults merged_kwargs = self._prepare_extra_chat_template_kwargs( chat_template_kwargs, default_chat_template_kwargs, ) _chat_template_kwargs: dict[str, Any] = dict( chat_template=chat_template, add_generation_prompt=add_generation_prompt, continue_final_message=continue_final_message, tools=tool_dicts, documents=documents, ) _chat_template_kwargs.update(merged_kwargs) request_prompt: str | list[int] if tokenizer is None: request_prompt = "placeholder" elif isinstance(tokenizer, MistralTokenizer): request_prompt = apply_mistral_chat_template( tokenizer, messages=messages, **_chat_template_kwargs, ) else: hf_chat_template_kwargs = dict(_chat_template_kwargs) hf_chat_template_kwargs.pop("tools", None) hf_chat_template_kwargs.pop("chat_template", None) request_prompt = apply_hf_chat_template( model_config=model_config, tokenizer=tokenizer, conversation=conversation, tools=tool_dicts, chat_template=chat_template, tokenize=False, **hf_chat_template_kwargs, ) # OMNI: Await the combined future to get both mm_data and mm_uuids mm_data, mm_uuids = await mm_future # 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 should_parse_tools = tool_parser is not None and ( hasattr(request, "tool_choice") and request.tool_choice != "none" ) if should_parse_tools: if not isinstance(request, ChatCompletionRequest): msg = "Tool usage is only supported for Chat Completions API" raise NotImplementedError(msg) request = tool_parser(tokenizer).adjust_request( # type: ignore request=request ) if tokenizer is None: assert isinstance(request_prompt, str), ( "Prompt has to be a string", "when the tokenizer is not initialised", ) prompt_inputs = TokensPrompt(prompt=request_prompt, prompt_token_ids=[1]) elif isinstance(request_prompt, str): prompt_inputs = await self._tokenize_prompt_input_async( request, tokenizer, request_prompt, add_special_tokens=add_special_tokens, ) else: # For MistralTokenizer assert is_list_of(request_prompt, int), "Prompt has to be either a string or a list of token ids" prompt_inputs = TokensPrompt( prompt=tokenizer.decode(request_prompt), prompt_token_ids=request_prompt, ) engine_prompt = TokensPrompt(prompt_token_ids=prompt_inputs["prompt_token_ids"]) if mm_data is not None: engine_prompt["multi_modal_data"] = mm_data if mm_uuids is not None: engine_prompt["multi_modal_uuids"] = mm_uuids mm_processor_kwargs = getattr(request, "mm_processor_kwargs", None) if mm_processor_kwargs is not None: engine_prompt["mm_processor_kwargs"] = mm_processor_kwargs if hasattr(request, "cache_salt") and request.cache_salt is not None: engine_prompt["cache_salt"] = request.cache_salt return conversation, [request_prompt], [engine_prompt] def _to_sampling_params_list(self, sampling_params_list: list[dict]) -> list[SamplingParams]: final_sampling_params_list = [] for sampling_params in sampling_params_list: if isinstance(sampling_params, dict): final_sampling_params_list.append(SamplingParams(**sampling_params)) elif isinstance(sampling_params, SamplingParams): final_sampling_params_list.append(sampling_params) else: raise ValueError(f"Invalid sampling params: {sampling_params}") return final_sampling_params_list def _get_comprehension_stage_index(self) -> int: for idx, stage in enumerate(self.engine_client.stage_list): if stage.is_comprehension: return idx raise ValueError("No comprehension stage (is_comprehension=True) found in stage_list") # OpenAI API standard sampling parameters that can be safely overridden. # These are the most commonly used parameters with compatible types # between ChatCompletionRequest and SamplingParams. # Users who need more control can use sampling_params_list in extra_body. _OPENAI_SAMPLING_FIELDS: set[str] = { "temperature", "top_p", "max_tokens", "seed", "stop", "frequency_penalty", "presence_penalty", } def _apply_request_overrides( self, default_params: SamplingParams, request: ChatCompletionRequest, ) -> SamplingParams: """Clone default params and override with user-provided request values. Starts with YAML defaults and only overrides fields that the user explicitly provided (non-None values) in the request. Args: default_params: Default SamplingParams from stage config YAML. request: The chat completion request containing user-provided values. Returns: New SamplingParams with YAML defaults overridden by request values. """ params = default_params.clone() for field_name in self._OPENAI_SAMPLING_FIELDS: value = getattr(request, field_name, None) if value is not None: setattr(params, field_name, value) return params def _build_sampling_params_list_from_request( self, request: ChatCompletionRequest, ) -> list[SamplingParams]: """Build sampling_params_list using standard OpenAI API parameters. For the comprehension stage, starts with YAML defaults and overrides with user-provided request values. For other stages, uses cloned YAML defaults. This approach ensures all YAML defaults (including seed, detokenize, etc.) are preserved while allowing users to override specific parameters. Args: request: The chat completion request containing OpenAI API parameters. Returns: List of SamplingParams, one for each stage. """ default_params_list = self.engine_client.default_sampling_params_list comprehension_idx = self._get_comprehension_stage_index() sampling_params_list = [] for idx, default_params in enumerate(default_params_list): if isinstance(default_params, dict): default_params = SamplingParams(**default_params) if idx == comprehension_idx: params = self._apply_request_overrides(default_params, request) sampling_params_list.append(params) else: # For other stages, clone default params sampling_params_list.append(default_params.clone()) return sampling_params_list def _log_inputs( self, request_id: str, inputs: PromptType, params_list: list[SamplingParams] | None, lora_request: LoRARequest | None, ) -> None: if self.request_logger is None: return prompt, prompt_token_ids, prompt_embeds = None, None, None if isinstance(inputs, str): prompt = inputs elif isinstance(inputs, list): prompt_token_ids = inputs else: prompt = getattr(inputs, "prompt", None) prompt_token_ids = getattr(inputs, "prompt_token_ids", None) logger.info( "Received request %s: prompt: %r, params_list: %s, prompt_token_ids: %s, prompt_embeds shape: %s, lora_request: %s.", # noqa: E501 request_id, prompt, params_list, prompt_token_ids, prompt_embeds.shape if prompt_embeds is not None else None, lora_request, ) async def chat_completion_stream_generator( self, request: ChatCompletionRequest, result_generator: AsyncIterator[RequestOutput], request_id: str, model_name: str, conversation: list[ConversationMessage], tokenizer: AnyTokenizer, request_metadata: RequestResponseMetadata, ): created_time = int(time.time()) chunk_object_type: Final = "chat.completion.chunk" first_iteration_dict = {} assert hasattr(request, "modalities") and request.modalities is not None, ( "Streaming request must specify output modalities" ) for modality in request.modalities: first_iteration_dict[modality] = True # Send response for each token for each request.n (index) num_choices = 1 if request.n is None else request.n previous_num_tokens = [0] * num_choices finish_reason_sent = [False] * num_choices num_prompt_tokens = 0 num_cached_tokens = None if self.use_harmony: harmony_parsers = [get_streamable_parser_for_assistant() for _ in range(num_choices)] harmony_tools_streamed = [False] * num_choices tools_streamed = [False] * num_choices if isinstance(request.tool_choice, ChatCompletionNamedToolChoiceParam): tool_choice_function_name = request.tool_choice.function.name else: tool_choice_function_name = None # Determine whether tools are in use with "auto" tool choice tool_choice_auto = not tool_choice_function_name and self._should_stream_with_auto_tool_parsing(request) all_previous_token_ids: list[list[int]] | None function_name_returned = [False] * num_choices if self.tool_call_id_type == "kimi_k2": history_tool_call_cnt = get_history_tool_calls_cnt(conversation) else: history_tool_call_cnt = 0 # Always track previous_texts for comprehensive output logging previous_texts = [""] * num_choices # Only one of these will be used, thus previous_texts and # all_previous_token_ids will not be used twice in the same iteration. if tool_choice_auto or self.reasoning_parser: # These are only required in "auto" tool choice case all_previous_token_ids = [[]] * num_choices # For reasoning parser and tool call all enabled added_content_delta_arr = [False] * num_choices reasoning_end_arr = [False] * num_choices else: all_previous_token_ids = None try: if self.reasoning_parser: chat_template_kwargs = self._prepare_extra_chat_template_kwargs( request.chat_template_kwargs, self.default_chat_template_kwargs, ) reasoning_parser = self.reasoning_parser( tokenizer, chat_template_kwargs=chat_template_kwargs, # type: ignore ) except RuntimeError as e: logger.exception("Error in reasoning parser creation.") data = self.create_streaming_error_response(e) yield f"data: {data}\n\n" yield "data: [DONE]\n\n" return # Prepare the tool parser if it's needed try: if tool_choice_auto and self.tool_parser: tool_parsers: list[ToolParser | None] = [self.tool_parser(tokenizer)] * num_choices else: tool_parsers = [None] * num_choices except Exception as e: logger.exception("Error in tool parser creation.") data = self.create_streaming_error_response(e) yield f"data: {data}\n\n" yield "data: [DONE]\n\n" return stream_options = request.stream_options include_usage, include_continuous_usage = should_include_usage(stream_options, self.enable_force_include_usage) try: async for omni_res in result_generator: final_output_type = omni_res.final_output_type res = omni_res.request_output if final_output_type not in first_iteration_dict: logger.warning(f"final output type: {final_output_type} is not needed by the request") continue if res.prompt_token_ids is not None: num_prompt_tokens = len(res.prompt_token_ids) if res.encoder_prompt_token_ids is not None: num_prompt_tokens += len(res.encoder_prompt_token_ids) # Initialize role before conditional blocks to avoid UnboundLocalError # when handling audio/image responses role = self.get_chat_request_role(request) # We need to do it here, because if there are exceptions in # the result_generator, it needs to be sent as the FIRST # response (by the try...catch). if first_iteration_dict[final_output_type] and final_output_type == "text": num_cached_tokens = res.num_cached_tokens # Send first response for each choice with role # NOTE: num_choices defaults to 1 so this usually executes once per request for i in range(num_choices): choice_data = ChatCompletionResponseStreamChoice( index=i, delta=DeltaMessage( role=role, content="", ), logprobs=None, finish_reason=None, ) # return prompt_token_ids at the first chunk ever chunk = OmniChatCompletionStreamResponse( id=request_id, object=chunk_object_type, created=created_time, choices=[choice_data], model=model_name, prompt_token_ids=(res.prompt_token_ids if request.return_token_ids else None), modality=final_output_type, ) # if continuous usage stats are requested, add it if include_continuous_usage: chunk.usage = UsageInfo( prompt_tokens=num_prompt_tokens, completion_tokens=0, total_tokens=num_prompt_tokens, ) data = chunk.model_dump_json(exclude_unset=True) yield f"data: {data}\n\n" # Send response to echo the input portion of the # last message if request.echo: last_msg_content: str | list[dict[str, str]] = "" if conversation and "content" in conversation[-1] and conversation[-1].get("role") == role: last_msg_content = conversation[-1]["content"] or "" if last_msg_content: for i in range(num_choices): choice_data = ChatCompletionResponseStreamChoice( index=i, delta=DeltaMessage(content=last_msg_content), logprobs=None, finish_reason=None, ) chunk = OmniChatCompletionStreamResponse( id=request_id, object=chunk_object_type, created=created_time, choices=[choice_data], model=model_name, modality=final_output_type, ) if include_continuous_usage: chunk.usage = UsageInfo( prompt_tokens=num_prompt_tokens, completion_tokens=0, total_tokens=num_prompt_tokens, ) data = chunk.model_dump_json(exclude_unset=True) yield f"data: {data}\n\n" first_iteration_dict[final_output_type] = False if final_output_type == "text": for output in res.outputs: i = output.index tool_parser = tool_parsers[i] if finish_reason_sent[i]: continue if request.logprobs and request.top_logprobs is not None: assert output.logprobs is not None, "Did not output logprobs" logprobs = self._create_chat_logprobs( token_ids=output.token_ids, top_logprobs=output.logprobs, tokenizer=tokenizer, num_output_top_logprobs=request.top_logprobs, return_as_token_id=request.return_tokens_as_token_ids, ) else: logprobs = None if self.use_harmony: harmony_parser = harmony_parsers[i] prev_recipient = harmony_parser.current_recipient delta_text = "" for token_id in output.token_ids: harmony_parser.process(token_id) delta_text += harmony_parser.last_content_delta or "" cur_channel = harmony_parser.current_channel cur_recipient = harmony_parser.current_recipient else: # output.text is cumulative, extract only the delta portion previous_text = previous_texts[i] if previous_texts else "" if output.text is not None: delta_text = output.text[len(previous_text) :] else: delta_text = "" if not delta_text and not output.token_ids and not previous_num_tokens[i]: # Chunked prefill case, don't return empty chunks continue delta_message: DeltaMessage | None # just update previous_texts and previous_token_ids if tool_choice_auto or self.reasoning_parser: assert previous_texts is not None assert all_previous_token_ids is not None previous_text = previous_texts[i] previous_token_ids = all_previous_token_ids[i] current_text = previous_text + delta_text # avoid the None + list error. if previous_token_ids: current_token_ids = previous_token_ids + as_list(output.token_ids) else: current_token_ids = as_list(output.token_ids) if self.use_harmony: if cur_channel == "final": delta_message = DeltaMessage(content=delta_text) elif cur_channel == "analysis": if request.include_reasoning: delta_message = DeltaMessage(reasoning=delta_text) else: delta_message = None elif ( cur_channel == "commentary" and cur_recipient and cur_recipient.startswith("functions.") ): # Count completed tool calls to determine index base_index = 0 for msg in harmony_parser.messages: if ( msg.channel == "commentary" and msg.recipient and msg.recipient.startswith("functions.") ): base_index += 1 if prev_recipient != cur_recipient: tool_name = cur_recipient.split("functions.", 1)[1] delta_message = DeltaMessage( tool_calls=[ DeltaToolCall( id=make_tool_call_id(), type="function", function=DeltaFunctionCall( name=tool_name, arguments="", ), index=base_index, ) ] ) elif delta_text: delta_message = DeltaMessage( tool_calls=[ DeltaToolCall( index=base_index, function=DeltaFunctionCall(arguments=delta_text), ) ] ) else: delta_message = None if delta_message is not None: harmony_tools_streamed[i] = True else: delta_message = None # handle streaming deltas for tools with named tool_choice elif tool_choice_function_name: if ( self.reasoning_parser and not reasoning_end_arr[i] and not reasoning_parser.is_reasoning_end(previous_token_ids) ): assert reasoning_parser is not None delta_message = reasoning_parser.extract_reasoning_streaming( previous_text, current_text, delta_text, previous_token_ids, current_token_ids, output.token_ids, ) # When encountering think end id in delta_token_ids # or think end id in prompt_token_ids # i.e {"enable_thinking": False}, # set reasoning status to end. # Only keep 'content', remove 'reasoning'. if reasoning_parser.is_reasoning_end(as_list(output.token_ids)) or ( res.prompt_token_ids and reasoning_parser.is_reasoning_end(res.prompt_token_ids) ): reasoning_end_arr[i] = True if delta_message and delta_message.content: # This need to be added to next `delta_text` current_text = delta_message.content delta_message.content = None else: current_text = "" else: # Just to add remaining `content` if self.reasoning_parser: delta_text = previous_text + delta_text current_text = "" if function_name_returned[i]: delta_tool_call = DeltaToolCall( function=DeltaFunctionCall(arguments=delta_text), index=i, ) else: delta_tool_call = DeltaToolCall( id=make_tool_call_id(), type="function", function=DeltaFunctionCall( name=tool_choice_function_name, arguments=delta_text, ), index=i, ) function_name_returned[i] = True delta_message = DeltaMessage( tool_calls=[ delta_tool_call, ] ) tools_streamed[i] = True elif request.tool_choice == "required": assert previous_texts is not None previous_text = previous_texts[i] current_text = previous_text + delta_text fn_name_returned = function_name_returned[i] output_token_ids = as_list(output.token_ids) if ( self.reasoning_parser is not None and not reasoning_end_arr[i] and res.prompt_token_ids and reasoning_parser.is_reasoning_end(res.prompt_token_ids) ): reasoning_end_arr[i] = True if self.reasoning_parser and not reasoning_end_arr[i]: delta_message = reasoning_parser.extract_reasoning_streaming( previous_text, current_text, delta_text, previous_token_ids, current_token_ids, output_token_ids, ) if reasoning_parser.is_reasoning_end(output_token_ids): reasoning_end_arr[i] = True if delta_message and delta_message.content: current_text = delta_message.content delta_message.content = None else: # reasoning ended current_text = "" else: # either finished reasoning or no reasoning at all content = current_text delta_message, function_name_returned[i] = self.extract_tool_call_required_streaming( previous_text=previous_text, current_text=content, delta_text=delta_text, function_name_returned=fn_name_returned, tool_call_idx=history_tool_call_cnt, ) if ( delta_message and delta_message.tool_calls and delta_message.tool_calls[0].id is not None ): history_tool_call_cnt += 1 tools_streamed[i] = True # handle streaming deltas for tools with "auto" tool choice # and reasoning parser elif tool_choice_auto and self.reasoning_parser: assert tool_parser is not None assert reasoning_parser is not None assert added_content_delta_arr is not None assert reasoning_end_arr is not None output_token_ids = as_list(output.token_ids) if not reasoning_end_arr[i]: delta_message = reasoning_parser.extract_reasoning_streaming( previous_text, current_text, delta_text, previous_token_ids, current_token_ids, output_token_ids, ) # When encountering think end id in prompt_token_ids # i.e {"enable_thinking": False}, # set reasoning status to end. # Remove the text and token ids related # to 'reasoning'. if res.prompt_token_ids and reasoning_parser.is_reasoning_end(res.prompt_token_ids): reasoning_end_arr[i] = True current_token_ids = output_token_ids if delta_message and delta_message.content: current_text = delta_message.content delta_message.content = None else: current_text = "" # When encountering think end id in delta_token_ids, # set reasoning status to end. # Remove the text and token ids related # to 'reasoning'. if reasoning_parser.is_reasoning_end(output_token_ids): reasoning_end_arr[i] = True current_token_ids = reasoning_parser.extract_content_ids(output_token_ids) if delta_message and delta_message.content: current_text = delta_message.content delta_message.content = None else: current_text = "" # handle tool calls only after reasoning is done, else: delta_token_ids = output_token_ids # First time to tool call, # add the remaining text and token ids # to delta from previous if not added_content_delta_arr[i]: added_content_delta_arr[i] = True previous_text = "" previous_token_ids = [] delta_text = current_text delta_token_ids = current_token_ids delta_message = tool_parser.extract_tool_calls_streaming( previous_text=previous_text, current_text=current_text, delta_text=delta_text, previous_token_ids=previous_token_ids, current_token_ids=current_token_ids, delta_token_ids=delta_token_ids, request=request, ) if delta_message and delta_message.tool_calls: tools_streamed[i] = True # when only tool calls elif tool_choice_auto: assert tool_parser is not None delta_message = tool_parser.extract_tool_calls_streaming( previous_text=previous_text, current_text=current_text, delta_text=delta_text, previous_token_ids=previous_token_ids, current_token_ids=current_token_ids, delta_token_ids=output.token_ids, request=request, ) if delta_message and delta_message.tool_calls: tools_streamed[i] = True # when only reasoning elif self.reasoning_parser: delta_message = reasoning_parser.extract_reasoning_streaming( previous_text, current_text, delta_text, previous_token_ids, current_token_ids, output.token_ids, ) # handle streaming just a content delta else: delta_message = DeltaMessage(content=delta_text) # update the previous values for the next iteration if (tool_choice_auto or self.reasoning_parser) and not self.use_harmony: assert previous_texts is not None assert all_previous_token_ids is not None previous_texts[i] = current_text all_previous_token_ids[i] = current_token_ids else: # Update for comprehensive logging even in simple case assert previous_texts is not None previous_texts[i] += delta_text # set the previous values for the next iteration previous_num_tokens[i] += len(output.token_ids) # if the message delta is None (e.g. because it was a # "control token" for tool calls or the parser otherwise # wasn't ready to send a token, then # get the next token without streaming a chunk if delta_message is None: if output.finish_reason is None and not request.return_token_ids: continue delta_message = DeltaMessage() # Log streaming delta if output logging is enabled if self.enable_log_outputs and self.request_logger: delta_content = "" if delta_message.content: delta_content = delta_message.content elif delta_message.tool_calls: delta_content = "".join( tc.function.arguments for tc in delta_message.tool_calls if tc.function and tc.function.arguments ) if delta_content: self.request_logger.log_outputs( request_id=request_id, outputs=delta_content, output_token_ids=as_list(output.token_ids), finish_reason=output.finish_reason, is_streaming=True, delta=True, ) if output.finish_reason is None: # Send token-by-token response for each request.n choice_data = ChatCompletionResponseStreamChoice( index=i, delta=delta_message, logprobs=logprobs, finish_reason=None, token_ids=(as_list(output.token_ids) if request.return_token_ids else None), ) # if the model is finished generating else: # check to make sure we haven't "forgotten" to stream # any tokens that were generated but previously # matched by partial json parsing # only happens if we are NOT using structured outputs auto_tools_called = False if tool_parser: auto_tools_called = len(tool_parser.prev_tool_call_arr) > 0 index = len(tool_parser.prev_tool_call_arr) - 1 if auto_tools_called else 0 else: index = 0 if self._should_check_for_unstreamed_tool_arg_tokens(delta_message, output) and tool_parser: latest_delta_len = 0 if ( isinstance( delta_message.tool_calls[0].function, DeltaFunctionCall, ) ) and isinstance(delta_message.tool_calls[0].function.arguments, str): latest_delta_len = len(delta_message.tool_calls[0].function.arguments) # get the expected call based on partial JSON # parsing which "autocompletes" the JSON expected_call = json.dumps( tool_parser.prev_tool_call_arr[index].get("arguments", {}), ensure_ascii=False, ) # get what we've streamed so far for arguments # for the current tool actual_call = tool_parser.streamed_args_for_tool[index] if latest_delta_len > 0: actual_call = actual_call[:-latest_delta_len] # check to see if there's anything left to stream remaining_call = expected_call.replace(actual_call, "", 1) # set that as a delta message delta_message = DeltaMessage( tool_calls=[ DeltaToolCall( index=index, function=DeltaFunctionCall(arguments=remaining_call).model_dump( exclude_none=True ), ) ] ) # Send the finish response for each request.n only once # In OpenAI's API, when a tool is called, the # finish_reason is: # "tool_calls" for "auto" or "required" tool calls, # and "stop" for named tool calls. if ( auto_tools_called or (tools_streamed[i] and not tool_choice_function_name) or (self.use_harmony and harmony_tools_streamed[i]) ): finish_reason_ = "tool_calls" else: finish_reason_ = output.finish_reason if output.finish_reason else "stop" choice_data = ChatCompletionResponseStreamChoice( index=i, delta=delta_message, logprobs=logprobs, finish_reason=finish_reason_, stop_reason=output.stop_reason, token_ids=(as_list(output.token_ids) if request.return_token_ids else None), ) finish_reason_sent[i] = True choice_data = maybe_filter_parallel_tool_calls(choice_data, request) chunk = OmniChatCompletionStreamResponse( id=request_id, object=chunk_object_type, created=created_time, choices=[choice_data], model=model_name, modality=final_output_type, ) # handle usage stats if requested & if continuous if include_continuous_usage: completion_tokens = previous_num_tokens[i] chunk.usage = UsageInfo( prompt_tokens=num_prompt_tokens, completion_tokens=completion_tokens, total_tokens=num_prompt_tokens + completion_tokens, ) data = chunk.model_dump_json(exclude_unset=True) yield f"data: {data}\n\n" elif final_output_type == "audio": role = self.get_chat_request_role(request) choices_data = self._create_audio_choice(omni_res, role, request, stream=True) chunk = OmniChatCompletionStreamResponse( id=request_id, object=chunk_object_type, created=created_time, choices=choices_data, model=model_name, modality=final_output_type, ) chunk.usage = UsageInfo( prompt_tokens=num_prompt_tokens, completion_tokens=0, total_tokens=num_prompt_tokens, ) data = chunk.model_dump_json(exclude_unset=True) yield f"data: {data}\n\n" else: logger.warning(f"Unsupported streaming final output type: {final_output_type}") continue # once the final token is handled, if stream_options.include_usage # is sent, send the usage if include_usage: completion_tokens = sum(previous_num_tokens) final_usage = UsageInfo( prompt_tokens=num_prompt_tokens, completion_tokens=completion_tokens, total_tokens=num_prompt_tokens + completion_tokens, ) if self.enable_prompt_tokens_details and num_cached_tokens: final_usage.prompt_tokens_details = PromptTokenUsageInfo(cached_tokens=num_cached_tokens) final_usage_chunk = ChatCompletionStreamResponse( id=request_id, object=chunk_object_type, created=created_time, choices=[], model=model_name, usage=final_usage, ) final_usage_data = final_usage_chunk.model_dump_json(exclude_unset=True, exclude_none=True) yield f"data: {final_usage_data}\n\n" # report to FastAPI middleware aggregate usage across all choices num_completion_tokens = sum(previous_num_tokens) request_metadata.final_usage_info = UsageInfo( prompt_tokens=num_prompt_tokens, completion_tokens=num_completion_tokens, total_tokens=num_prompt_tokens + num_completion_tokens, ) # Log complete streaming response if output logging is enabled if self.enable_log_outputs and self.request_logger: # Log the complete response for each choice for i in range(num_choices): full_text = ( previous_texts[i] if previous_texts and i < len(previous_texts) else f"" ) self.request_logger.log_outputs( request_id=request_id, outputs=full_text, output_token_ids=None, # Consider also logging all token IDs finish_reason="streaming_complete", is_streaming=True, delta=False, ) except Exception as e: logger.exception("Error in chat completion stream generator.") data = self.create_streaming_error_response(e) yield f"data: {data}\n\n" # Send the final done message after all response.n are finished yield "data: [DONE]\n\n" async def chat_completion_full_generator( self, request: ChatCompletionRequest, result_generator: AsyncIterator[RequestOutput], request_id: str, model_name: str, conversation: list[ConversationMessage], tokenizer: TokenizerLike, request_metadata: RequestResponseMetadata, ) -> ErrorResponse | ChatCompletionResponse: created_time = int(time.time()) final_res: RequestOutput | None = None final_outputs: list[OmniRequestOutput] = [] try: async for res in result_generator: final_outputs.append(res) except asyncio.CancelledError: return self.create_error_response("Client disconnected") except ValueError as e: return self.create_error_response(e) assert final_outputs is not None choices: list[ChatCompletionResponseChoice] = [] usage = UsageInfo(prompt_tokens=0, completion_tokens=0, total_tokens=0) role = self.get_chat_request_role(request) prompt_logprobs = None prompt_token_ids = None kv_transfer_params = None # Build requested modalities set for filtering requested_modalities = ( set(request.modalities) if hasattr(request, "modalities") and request.modalities else None ) for omni_outputs in final_outputs: choices_data = [] if omni_outputs.request_output is not None and not getattr(omni_outputs.request_output, "finished", False): continue # Filter outputs based on requested modalites if requested_modalities is not None and omni_outputs.final_output_type not in requested_modalities: logger.warning(f"final output type: {omni_outputs.final_output_type} is not needed by the request") continue if omni_outputs.final_output_type == "text": ( choices_data, usage, prompt_logprobs, prompt_token_ids, kv_transfer_params, ) = self._create_text_choice(request, omni_outputs, tokenizer, conversation, role) elif omni_outputs.final_output_type == "audio": choices_data = self._create_audio_choice(omni_outputs, role, request, stream=False) elif omni_outputs.final_output_type == "image": choices_data = self._create_image_choice(omni_outputs, role, request, stream=False) else: logger.warning(f"Unsupported final output type: {omni_outputs.final_output_type}") continue choices.extend(choices_data) response = ChatCompletionResponse( id=request_id, created=created_time, model=model_name, choices=choices, usage=usage, prompt_logprobs=prompt_logprobs, prompt_token_ids=prompt_token_ids, kv_transfer_params=kv_transfer_params, ) # Log complete response if output logging is enabled if self.enable_log_outputs and self.request_logger: for choice in choices: output_text = "" if choice.message.content: output_text = choice.message.content elif choice.message.tool_calls: # For tool calls, log the function name and arguments tool_call_descriptions = [] for tc in choice.message.tool_calls: if hasattr(tc.function, "name") and hasattr(tc.function, "arguments"): tool_call_descriptions.append(f"{tc.function.name}({tc.function.arguments})") tool_calls_str = ", ".join(tool_call_descriptions) output_text = f"[tool_calls: {tool_calls_str}]" if output_text: # Get the corresponding output token IDs output_token_ids = None if choice.index < len(final_res.outputs): output_token_ids = final_res.outputs[choice.index].token_ids self.request_logger.log_outputs( request_id=request_id, outputs=output_text, output_token_ids=output_token_ids, finish_reason=choice.finish_reason, is_streaming=False, delta=False, ) return response def _create_text_choice( self, request: ChatCompletionRequest, omni_outputs: OmniRequestOutput, tokenizer: TokenizerLike, conversation: list[ConversationMessage], role: str, ): final_res = omni_outputs.request_output if self.tool_call_id_type == "kimi_k2": history_tool_call_cnt = get_history_tool_calls_cnt(conversation) else: history_tool_call_cnt = 0 choices: list[ChatCompletionResponseChoice] = [] for output in final_res.outputs: token_ids = output.token_ids out_logprobs = output.logprobs tool_call_info = None if request.logprobs and request.top_logprobs is not None: assert out_logprobs is not None, "Did not output logprobs" logprobs = self._create_chat_logprobs( token_ids=token_ids, top_logprobs=out_logprobs, num_output_top_logprobs=request.top_logprobs, tokenizer=tokenizer, return_as_token_id=request.return_tokens_as_token_ids, ) else: logprobs = None if self.use_harmony: reasoning_content, content, _ = parse_chat_output(token_ids) if not request.include_reasoning: reasoning_content = None if self.tool_parser is not None: tool_parser = self.tool_parser(tokenizer) # NOTE: We use token_ids for openai tool parser tool_call_info = tool_parser.extract_tool_calls( "", request=request, token_ids=token_ids, # type: ignore ) content = tool_call_info.content message = ChatMessage( role=role, reasoning_content=reasoning_content, content=content, tool_calls=tool_call_info.tool_calls, ) else: message = ChatMessage( role=role, reasoning_content=reasoning_content, content=content, ) choice_data = ChatCompletionResponseChoice( index=output.index, message=message, logprobs=logprobs, finish_reason=( "tool_calls" if (tool_call_info is not None and tool_call_info.tools_called) else (output.finish_reason if output.finish_reason else "stop") ), stop_reason=output.stop_reason, ) choices.append(choice_data) continue if self.reasoning_parser: try: chat_template_kwargs = self._prepare_extra_chat_template_kwargs( request.chat_template_kwargs, self.default_chat_template_kwargs, ) reasoning_parser = self.reasoning_parser( tokenizer, chat_template_kwargs=chat_template_kwargs, # type: ignore ) except RuntimeError as e: logger.exception("Error in reasoning parser creation.") return self.create_error_response(e) # If the reasoning parser is enabled, # tool calls are extracted exclusively from the content. reasoning_content, content = reasoning_parser.extract_reasoning(output.text, request=request) if not request.include_reasoning: reasoning_content = None else: reasoning_content = None content = output.text auto_tools_called = False # if auto tools are not enabled, and a named tool choice using # outlines is not being used if (not self.enable_auto_tools or not self.tool_parser) and ( not isinstance(request.tool_choice, ChatCompletionNamedToolChoiceParam) and request.tool_choice != "required" ): message = ChatMessage(role=role, reasoning_content=reasoning_content, content=content) # if the request uses tools and specified a tool choice elif request.tool_choice and type(request.tool_choice) is ChatCompletionNamedToolChoiceParam: tool_call_class = MistralToolCall if isinstance(tokenizer, MistralTokenizer) else ToolCall message = ChatMessage( role=role, reasoning_content=reasoning_content, content="", tool_calls=[ tool_call_class( function=FunctionCall( name=request.tool_choice.function.name, arguments=content, ) ) ], ) elif request.tool_choice and request.tool_choice == "required": tool_call_class = MistralToolCall if isinstance(tokenizer, MistralTokenizer) else ToolCall # the fields of FunctionDefinition are a superset of the # tool call outputs and can be used for parsing assert content is not None tool_calls = TypeAdapter(list[FunctionDefinition]).validate_json(content) tool_call_ids = [] for tool_call in tool_calls: tool_call_ids.append( make_tool_call_id( id_type=self.tool_call_id_type, func_name=tool_call.name, idx=history_tool_call_cnt, ) ) history_tool_call_cnt += 1 message = ChatMessage( role=role, content="", tool_calls=[ tool_call_class( id=tool_call_ids[i], function=FunctionCall( name=tool_call.name, arguments=json.dumps(tool_call.parameters, ensure_ascii=False), ), ) for i, tool_call in enumerate(tool_calls) ], reasoning_content=reasoning_content, ) # if the request doesn't use tool choice # OR specifies to not use a tool elif not request.tool_choice or request.tool_choice == "none": message = ChatMessage(role=role, reasoning_content=reasoning_content, content=content) # handle when there are tools and tool choice is auto elif ( request.tools and (request.tool_choice == "auto" or request.tool_choice is None) and self.enable_auto_tools and self.tool_parser ): try: tool_parser = self.tool_parser(tokenizer) except RuntimeError as e: logger.exception("Error in tool parser creation.") return self.create_error_response(e) tool_call_info = tool_parser.extract_tool_calls(content if content is not None else "", request=request) # In the OpenAI API the finish_reason is "tools_called" # if the tool choice is auto and the model produced a tool # call. The same is not true for named function calls auto_tools_called = tool_call_info.tools_called if tool_call_info.tools_called: message = ChatMessage( role=role, reasoning_content=reasoning_content, content=tool_call_info.content, tool_calls=tool_call_info.tool_calls, ) else: # FOR NOW make it a chat message; we will have to detect # the type to make it later. ret_content = content # try to use content return from tool parser first, # tool parser may do some modify for the content. if tool_call_info.content and len(tool_call_info.content) > 0: ret_content = tool_call_info.content message = ChatMessage( role=role, reasoning_content=reasoning_content, content=ret_content, ) # undetermined case that is still important to handle else: logger.error( "Error in chat_completion_full_generator - cannot determine if tools should be extracted. " "Returning a standard chat completion." ) message = ChatMessage(role=role, reasoning_content=reasoning_content, content=content) choice_data = ChatCompletionResponseChoice( index=output.index, message=message, logprobs=logprobs, finish_reason=( "tool_calls" if auto_tools_called else output.finish_reason if output.finish_reason else "stop" ), stop_reason=output.stop_reason, token_ids=(as_list(output.token_ids) if request.return_token_ids else None), ) choices.append(choice_data) if request.echo: last_msg_content: str | list[dict[str, str]] = "" if conversation and "content" in conversation[-1] and conversation[-1].get("role") == role: last_msg_content = conversation[-1]["content"] or "" if isinstance(last_msg_content, list): last_msg_content = "\n".join(msg["text"] for msg in last_msg_content) for choice in choices: full_message = last_msg_content + (choice.message.content or "") choice.message.content = full_message assert final_res.prompt_token_ids is not None num_prompt_tokens = len(final_res.prompt_token_ids) if final_res.encoder_prompt_token_ids is not None: num_prompt_tokens += len(final_res.encoder_prompt_token_ids) num_generated_tokens = sum(len(output.token_ids) for output in final_res.outputs) usage = UsageInfo( prompt_tokens=num_prompt_tokens, completion_tokens=num_generated_tokens, total_tokens=num_prompt_tokens + num_generated_tokens, ) if self.enable_prompt_tokens_details and final_res.num_cached_tokens: usage.prompt_tokens_details = PromptTokenUsageInfo(cached_tokens=final_res.num_cached_tokens) prompt_logprobs = clamp_prompt_logprobs(final_res.prompt_logprobs) prompt_token_ids = final_res.prompt_token_ids if request.return_token_ids else None kv_transfer_params = final_res.kv_transfer_params return choices, usage, prompt_logprobs, prompt_token_ids, kv_transfer_params def _create_audio_choice( self, omni_outputs: OmniRequestOutput, role: str, request: ChatCompletionRequest, stream: bool = False ): choices: list[ChatCompletionResponseChoice] = [] final_res = omni_outputs.request_output # OMNI: Access multimodal_output from CompletionOutput (outputs[0]), not from RequestOutput # Reference: examples/offline_inference/qwen3_omni/end2end.py line 421 audio_data = final_res.outputs[0].multimodal_output.get("audio") if stream: audio_tensor = audio_data[-1].float().detach().cpu().numpy() else: if isinstance(audio_data, list): audio_data = torch.cat(audio_data, dim=-1) audio_tensor = audio_data.float().detach().cpu().numpy() # Ensure audio is 1D (flatten if needed) if audio_tensor.ndim > 1: audio_tensor = audio_tensor.flatten() audio_obj = CreateAudio( audio_tensor=audio_tensor, sample_rate=24000, response_format="wav", speed=1.0, stream_format="audio", base64_encode=True, ) audio_response: AudioResponse = self.create_audio(audio_obj) audio_base64 = audio_response.audio_data # Generate unique ID for the audio audio_id = f"audio-{uuid.uuid4().hex[:16]}" # Set expiration time (e.g., 24 hours from now) as Unix timestamp expires_at = int((datetime.now(timezone.utc) + timedelta(hours=24)).timestamp()) # Create OpenAIChatCompletionAudio object with all required fields audio_obj = OpenAIChatCompletionAudio( id=audio_id, data=audio_base64, expires_at=expires_at, transcript="", # Empty transcript if not available ) for output in final_res.outputs: if stream: choice_data = ChatCompletionResponseStreamChoice( index=output.index, delta=DeltaMessage(role=role, content=audio_base64), logprobs=None, finish_reason="stop", stop_reason=output.stop_reason, token_ids=(as_list(output.token_ids) if request.return_token_ids else None), ) else: choice_data = ChatCompletionResponseChoice( index=output.index, message=ChatMessage(role=role, audio=audio_obj), logprobs=None, finish_reason="stop", stop_reason=None, ) choices.append(choice_data) return choices def _create_image_choice( self, omni_outputs: OmniRequestOutput, role: str, request: ChatCompletionRequest, stream: bool = False ): """Create chat completion response choices for image output. Converts image tensor or PIL Image output from diffusion models into base64-encoded image data for API response. Args: omni_outputs: Output containing image data from diffusion stage role: The role for the response message (e.g., "assistant") Returns: List of ChatCompletionResponseChoice with image content """ from PIL import Image choices: list[ChatCompletionResponseChoice] = [] final_res = omni_outputs.request_output # Handle different image output formats images = [] # First check omni_outputs.images directly (for diffusion mode via from_diffusion) if omni_outputs.images: images = omni_outputs.images # Fall back to request_output for pipeline mode # OMNI: Access multimodal_output from CompletionOutput (outputs[0]), not from RequestOutput elif final_res is not None and final_res.outputs: completion_output = final_res.outputs[0] if hasattr(completion_output, "multimodal_output") and completion_output.multimodal_output: image_data = completion_output.multimodal_output.get("image") if image_data is not None: if isinstance(image_data, Image.Image): images.append(image_data) elif hasattr(image_data, "cpu"): # Tensor import numpy as np # Convert tensor to PIL Image img_array = image_data.float().detach().cpu().numpy() # Handle different tensor formats (CHW -> HWC) if img_array.ndim == 3 and img_array.shape[0] in [1, 3, 4]: img_array = np.transpose(img_array, (1, 2, 0)) # Normalize to 0-255 if img_array.max() <= 1.0: img_array = (img_array * 255).astype(np.uint8) else: img_array = img_array.astype(np.uint8) # Handle grayscale if img_array.ndim == 2: images.append(Image.fromarray(img_array, mode="L")) elif img_array.shape[-1] == 1: images.append(Image.fromarray(img_array.squeeze(-1), mode="L")) elif img_array.shape[-1] == 3: images.append(Image.fromarray(img_array, mode="RGB")) elif img_array.shape[-1] == 4: images.append(Image.fromarray(img_array, mode="RGBA")) elif hasattr(final_res, "images") and final_res.images: images = final_res.images # Convert images to base64 image_contents = [] for img in images: with BytesIO() as buffer: img.save(buffer, format="PNG") img_bytes = buffer.getvalue() img_base64 = base64.b64encode(img_bytes).decode("utf-8") image_contents.append( { "type": "image_url", "image_url": { "url": f"data:image/png;base64,{img_base64}", }, } ) # Create message content if len(image_contents) == 1: content = image_contents elif len(image_contents) > 1: content = image_contents else: content = [{"type": "text", "text": "Image generation completed but no images were produced."}] # Create response choice # Use model_construct to bypass validation for multimodal content # (ChatMessage.content only accepts str, but we need list for images) # Then use object.__setattr__ to directly set the field, bypassing Pydantic's type checking import warnings as warnings_module with warnings_module.catch_warnings(): warnings_module.filterwarnings("ignore", category=UserWarning, module="pydantic") message = ChatMessage.model_construct(role=role) object.__setattr__(message, "content", content) # Mark content as set in fields_set to ensure proper serialization if hasattr(message, "__pydantic_fields_set__"): message.__pydantic_fields_set__.add("content") choice_data = ChatCompletionResponseChoice( index=0, message=message, logprobs=None, finish_reason="stop", stop_reason=None, ) choices.append(choice_data) return choices # ==================== Diffusion Mode Methods ==================== async def _create_diffusion_chat_completion( self, request: ChatCompletionRequest, raw_request: Request | None = None, ) -> ChatCompletionResponse | ErrorResponse: """Generate images via chat completion interface for diffusion models. Args: request: Chat completion request raw_request: Raw FastAPI request object Returns: ChatCompletionResponse with generated images or ErrorResponse """ try: request_id = f"chatcmpl-{uuid.uuid4().hex[:16]}" created_time = int(time.time()) # Convert messages to dict format messages = [] for msg in request.messages: if hasattr(msg, "model_dump"): messages.append(msg.model_dump()) elif isinstance(msg, dict): messages.append(msg) else: messages.append({"role": getattr(msg, "role", "user"), "content": getattr(msg, "content", "")}) # Extract prompt and images from messages prompt, reference_images = self._extract_diffusion_prompt_and_images(messages) if not prompt: return self._create_error_response("No text prompt found in messages") # Extract generation parameters from extra_body (preferred) # Reference: text_to_image.py and text_to_video.py for supported parameters extra_body = getattr(request, "extra_body", None) or {} # Parse size if provided (supports "1024x1024" format) height = extra_body.get("height") width = extra_body.get("width") if "size" in extra_body: try: size_str = extra_body["size"] if isinstance(size_str, str) and "x" in size_str.lower(): w, h = size_str.lower().split("x") width, height = int(w), int(h) except ValueError: logger.warning("Invalid size format: %s", extra_body.get("size")) # Get request parameters from extra_body # Text-to-image parameters (ref: text_to_image.py) num_inference_steps = extra_body.get("num_inference_steps", 50) guidance_scale = extra_body.get("guidance_scale") true_cfg_scale = extra_body.get("true_cfg_scale") # Qwen-Image specific seed = extra_body.get("seed") negative_prompt = extra_body.get("negative_prompt") num_outputs_per_prompt = extra_body.get("num_outputs_per_prompt", 1) # Text-to-video parameters (ref: text_to_video.py) num_frames = extra_body.get("num_frames") guidance_scale_2 = extra_body.get("guidance_scale_2") # For video high-noise CFG lora_body = extra_body.get("lora") logger.info( "Diffusion chat request %s: prompt=%r, ref_images=%d, params=%s", request_id, prompt[:50] + "..." if len(prompt) > 50 else prompt, len(reference_images), {k: v for k, v in extra_body.items() if v is not None}, ) # Decode reference images if provided pil_images: list[Image.Image] = [] for img_b64 in reference_images: try: img_bytes = base64.b64decode(img_b64) pil_images.append(Image.open(BytesIO(img_bytes))) except Exception as e: logger.warning("Failed to decode reference image: %s", e) # Build generation kwargs gen_prompt: OmniTextPrompt = { "prompt": prompt, "negative_prompt": negative_prompt, } gen_params = OmniDiffusionSamplingParams( num_inference_steps=num_inference_steps, height=height, width=width, num_outputs_per_prompt=num_outputs_per_prompt, seed=seed, ) if guidance_scale is not None: gen_params.guidance_scale = guidance_scale # Add Qwen-Image specific parameter if true_cfg_scale is not None: gen_params.true_cfg_scale = true_cfg_scale # Add video generation parameters if set if num_frames is not None: gen_params.num_frames = num_frames if guidance_scale_2 is not None: gen_params.guidance_scale_2 = guidance_scale_2 # Parse per-request LoRA (works for both AsyncOmniDiffusion and AsyncOmni). if lora_body and isinstance(lora_body, dict): try: lora_name = lora_body.get("name") or lora_body.get("lora_name") or lora_body.get("adapter") lora_path = ( lora_body.get("local_path") or lora_body.get("path") or lora_body.get("lora_path") or lora_body.get("lora_local_path") ) # using "or" directly here may be buggy if `scale=0` lora_scale = lora_body.get("scale") if lora_scale is None: lora_scale = lora_body.get("lora_scale") lora_int_id = lora_body.get("int_id") if lora_int_id is None: lora_int_id = lora_body.get("lora_int_id") if lora_int_id is None and lora_path: lora_int_id = stable_lora_int_id(str(lora_path)) if lora_name and lora_path: lora_req = LoRARequest(str(lora_name), int(lora_int_id), str(lora_path)) gen_params.lora_request = lora_req if lora_scale is not None: gen_params.lora_scale = float(lora_scale) except Exception as e: # pragma: no cover - safeguard logger.warning("Failed to parse LoRA request: %s", e) # Add reference image if provided if pil_images: if len(pil_images) == 1: gen_prompt["multi_modal_data"] = {} gen_prompt["multi_modal_data"]["image"] = pil_images[0] else: od_config = getattr(self._diffusion_engine, "od_config", None) supports_multimodal_inputs = getattr(od_config, "supports_multimodal_inputs", False) if od_config is None: # TODO: entry is asyncOmni. We hack the od config here. supports_multimodal_inputs = True if supports_multimodal_inputs: gen_prompt["multi_modal_data"] = {} gen_prompt["multi_modal_data"]["image"] = pil_images else: return self._create_error_response( "Multiple input images are not supported by the current diffusion model. " "For multi-image editing, start the server with Qwen-Image-Edit-2509 " "and send multiple images in the user message content.", status_code=400, ) # Generate image # Handle both AsyncOmniDiffusion (returns OmniRequestOutput) and AsyncOmni (returns AsyncGenerator) if hasattr(self._diffusion_engine, "stage_list"): # AsyncOmni: iterate through async generator to get final output diffusion_engine = cast(AsyncOmni, self._diffusion_engine) result = None async for output in diffusion_engine.generate( prompt=gen_prompt, sampling_params_list=[gen_params], # Pass as single-stage params request_id=request_id, ): result = output if result is None: return self._create_error_response("No output generated from AsyncOmni") else: # AsyncOmniDiffusion: direct call diffusion_engine = cast(AsyncOmniDiffusion, self._diffusion_engine) result = await diffusion_engine.generate( prompt=gen_prompt, sampling_params=gen_params, request_id=request_id, ) # Extract images from result # Handle nested OmniRequestOutput structure where images might be in request_output images = getattr(result.request_output, "images", []) # Convert images to base64 content image_contents: list[dict[str, Any]] = [] for img in images: with BytesIO() as buffer: img.save(buffer, format="PNG") img_bytes = buffer.getvalue() img_base64 = base64.b64encode(img_bytes).decode("utf-8") image_contents.append( { "type": "image_url", "image_url": { "url": f"data:image/png;base64,{img_base64}", }, } ) # Build response if not image_contents: content = "Image generation completed but no images were produced." else: content = image_contents # Use model_construct to bypass validation for multimodal content # (ChatMessage.content only accepts str, but we need list for images) # Then use object.__setattr__ to directly set the field, bypassing Pydantic's type checking import warnings as warnings_module with warnings_module.catch_warnings(): warnings_module.filterwarnings("ignore", category=UserWarning, module="pydantic") message = ChatMessage.model_construct(role="assistant") object.__setattr__(message, "content", content) # Mark content as set in fields_set to ensure proper serialization if hasattr(message, "__pydantic_fields_set__"): message.__pydantic_fields_set__.add("content") choice = ChatCompletionResponseChoice.model_construct( index=0, message=message, finish_reason="stop", logprobs=None, stop_reason=None, ) response = ChatCompletionResponse( id=request_id, created=created_time, model=self._diffusion_model_name, choices=[choice], usage=UsageInfo( prompt_tokens=len(prompt.split()), completion_tokens=1, total_tokens=len(prompt.split()) + 1, ), ) logger.info( "Diffusion chat completed for request %s: %d images", request_id, len(images), ) return response except Exception as e: logger.exception("Diffusion chat completion failed: %s", e) return self._create_error_response( f"Image generation failed: {str(e)}", status_code=500, ) def _extract_diffusion_prompt_and_images( self, messages: list[dict[str, Any]], ) -> tuple[str, list[str]]: """Extract text prompt and base64 images from chat messages. Args: messages: List of chat messages Returns: Tuple of (prompt_text, list_of_base64_images) """ prompt_parts: list[str] = [] images: list[str] = [] for message in messages: role = message.get("role", "") if role != "user": continue content = message.get("content", "") # String content if isinstance(content, str): prompt_parts.append(content) continue # List of content items if isinstance(content, list): for item in content: if isinstance(item, str): prompt_parts.append(item) elif isinstance(item, dict): # Handle {"type": "text", "text": "..."} format if item.get("type") == "text": prompt_parts.append(item.get("text", "")) # Handle {"text": "..."} format elif "text" in item and "type" not in item: prompt_parts.append(item["text"]) # Handle {"type": "image_url", "image_url": {"url": "..."}} elif item.get("type") == "image_url": url = item.get("image_url", {}).get("url", "") if url.startswith("data:image"): try: _, b64_data = url.split(",", 1) images.append(b64_data) except ValueError: logger.warning("Invalid data URL format") # Handle {"image": "base64..."} format elif "image" in item: images.append(item["image"]) prompt = " ".join(prompt_parts).strip() return prompt, images def _create_error_response( self, message: str, err_type: str = "BadRequestError", status_code: int = 400, ) -> ErrorResponse: """Create an error response following OpenAI error format.""" return ErrorResponse( error=ErrorInfo( message=message, type=err_type, code=status_code, ) )