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chore: import upstream snapshot with attribution
2026-07-13 12:55:37 +08:00

1185 lines
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Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
import asyncio
import io
import time
from collections.abc import AsyncGenerator, AsyncIterator
from collections.abc import Sequence as GenericSequence
from http import HTTPStatus
from typing import Any, Final, cast
import numpy as np
import pybase64 as base64
from fastapi import Request
from vllm.engine.protocol import EngineClient
from vllm.entrypoints.chat_utils import (
ChatTemplateContentFormatOption,
ConversationMessage,
make_tool_call_id,
)
from vllm.entrypoints.generate.base.serving import (
GenerateBaseServing,
GenerationError,
build_per_request_timing_metrics,
clamp_prompt_logprobs,
format_token_id_placeholder,
)
from vllm.entrypoints.openai.chat_completion.protocol import (
ChatCompletionLogProb,
ChatCompletionLogProbs,
ChatCompletionLogProbsContent,
ChatCompletionNamedToolChoiceParam,
ChatCompletionRequest,
ChatCompletionResponse,
ChatCompletionResponseChoice,
ChatCompletionResponseStreamChoice,
ChatCompletionStreamResponse,
ChatMessage,
)
from vllm.entrypoints.openai.engine.protocol import (
DeltaMessage,
ErrorResponse,
FunctionCall,
PerRequestTimingMetrics,
PromptTokenUsageInfo,
RequestResponseMetadata,
ToolCall,
UsageInfo,
)
from vllm.entrypoints.openai.models.serving import OpenAIServingModels
from vllm.entrypoints.serve.utils.api_utils import get_max_tokens, should_include_usage
from vllm.entrypoints.serve.utils.request_logger import RequestLogger
from vllm.entrypoints.serve.utils.tool_calls_utils import (
maybe_filter_parallel_tool_calls,
)
from vllm.inputs import EngineInput, MultiModalPlaceholders
from vllm.logger import init_logger
from vllm.logprobs import Logprob
from vllm.outputs import RequestOutput
from vllm.parser import ParserManager
from vllm.parser.abstract_parser import Parser
from vllm.renderers import ChatParams
from vllm.renderers.online_renderer import OnlineRenderer
from vllm.sampling_params import BeamSearchParams, SamplingParams
from vllm.tokenizers import TokenizerLike
from vllm.utils.collection_utils import as_list
from vllm.utils.mistral import is_mistral_tool_parser
logger = init_logger(__name__)
def _get_mm_token_counts(engine_input: EngineInput) -> dict[str, int]:
"""Sum per-modality placeholder tokens from ``mm_placeholders``.
Keyed by modality name; ``PlaceholderRange.length`` is the placeholder's
prompt token span, so each sum matches the placeholder tokens already
counted in ``usage.prompt_tokens``.
"""
mm_placeholders = cast(
MultiModalPlaceholders | None, engine_input.get("mm_placeholders")
)
return {
modality: sum(p.length for p in ranges)
for modality, ranges in (mm_placeholders or {}).items()
if ranges
}
def _make_prompt_tokens_details(
enable_prompt_tokens_details: bool,
num_cached_tokens: int | None,
mm_token_counts: dict[str, int] | None,
) -> PromptTokenUsageInfo | None:
"""Build ``prompt_tokens_details`` from cached + multimodal token counts."""
if not enable_prompt_tokens_details:
return None
if num_cached_tokens is None and not mm_token_counts:
return None
return PromptTokenUsageInfo(
cached_tokens=num_cached_tokens,
multimodal_tokens=mm_token_counts or None,
)
class OpenAIServingChat(GenerateBaseServing):
def __init__(
self,
engine_client: EngineClient,
models: OpenAIServingModels,
response_role: str,
*,
online_renderer: "OnlineRenderer",
request_logger: RequestLogger | None,
chat_template: str | None,
chat_template_content_format: ChatTemplateContentFormatOption,
trust_request_chat_template: bool = False,
return_tokens_as_token_ids: bool = False,
reasoning_parser: str = "",
enable_auto_tools: bool = False,
exclude_tools_when_tool_choice_none: bool = False,
tool_parser: str | None = None,
enable_prompt_tokens_details: bool = False,
enable_force_include_usage: bool = False,
enable_log_outputs: bool = False,
enable_log_deltas: bool = True,
default_chat_template_kwargs: dict[str, Any] | None = None,
enable_per_request_metrics: bool = False,
) -> None:
super().__init__(
engine_client=engine_client,
models=models,
request_logger=request_logger,
return_tokens_as_token_ids=return_tokens_as_token_ids,
)
self.online_renderer = online_renderer
self.response_role = response_role
self.chat_template = chat_template
self.chat_template_content_format: Final = chat_template_content_format
self.trust_request_chat_template = trust_request_chat_template
self.default_chat_template_kwargs = default_chat_template_kwargs or {}
self.enable_log_outputs = enable_log_outputs
self.enable_log_deltas = enable_log_deltas
self.enable_auto_tools: bool = enable_auto_tools
self.parser_cls = ParserManager.get_parser(
tool_parser_name=tool_parser,
reasoning_parser_name=reasoning_parser,
enable_auto_tools=enable_auto_tools,
model_name=self.model_config.model,
is_harmony=self.model_config.hf_config.model_type == "gpt_oss",
)
if (
self.parser_cls is not None
and is_mistral_tool_parser(self.parser_cls.tool_parser_cls)
and self.parser_cls.reasoning_parser_cls is not None
):
from vllm.tool_parsers.mistral_tool_parser import MistralToolParser
MistralToolParser.model_can_reason = True
self.exclude_tools_when_tool_choice_none = exclude_tools_when_tool_choice_none
self.enable_prompt_tokens_details = enable_prompt_tokens_details
self.enable_force_include_usage = enable_force_include_usage
self.enable_per_request_metrics = enable_per_request_metrics
self.default_sampling_params = self.model_config.get_diff_sampling_param()
mc = self.model_config
self.override_max_tokens = (
self.default_sampling_params.get("max_tokens")
if mc.generation_config not in ("auto", "vllm")
else getattr(mc, "override_generation_config", {}).get("max_new_tokens")
)
# NOTE(woosuk): While OpenAI's chat completion API supports browsing
# for some models, currently vLLM doesn't support it. Please use the
# Responses API instead.
self.supports_browsing = False
self.browser_tool = None
# NOTE(woosuk): Chat completion API does not support code interpreter.
# Please use the Responses API instead.
self.supports_code_interpreter = False
self.python_tool = None
def warmup(self) -> None:
self.renderer.warmup(
ChatParams(
chat_template=self.chat_template,
chat_template_content_format=self.chat_template_content_format,
chat_template_kwargs=self.default_chat_template_kwargs,
)
)
def _effective_chat_template_kwargs(
self, request: ChatCompletionRequest
) -> dict[str, Any]:
return (
request.build_chat_params(
self.chat_template,
self.chat_template_content_format,
)
.with_defaults(self.default_chat_template_kwargs)
.chat_template_kwargs
)
async def render_chat_request(
self,
request: ChatCompletionRequest,
) -> tuple[list[ConversationMessage], list[EngineInput]] | ErrorResponse:
"""
Validate the model and preprocess a chat completion request.
Delegates preprocessing logic to OnlineRenderer, adding the
engine-aware checks (LoRA model validation, engine health).
Returns:
A tuple of (conversation, engine_inputs) on success,
or an ErrorResponse on failure.
"""
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
return await self.online_renderer.render_chat(request)
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.
"""
return await self._with_kv_transfer_rejection_cleanup(
self._create_chat_completion(request, raw_request), request, raw_request
)
async def _create_chat_completion(
self,
request: ChatCompletionRequest,
raw_request: Request | None = None,
) -> AsyncGenerator[str, None] | ChatCompletionResponse | ErrorResponse:
# Streaming response
tokenizer = self.renderer.tokenizer
assert tokenizer is not None
chat_template_kwargs = self._effective_chat_template_kwargs(request)
parser: Parser | None = None
if self.parser_cls is not None:
parser = self.parser_cls(
tokenizer,
request.tools,
chat_template_kwargs=chat_template_kwargs,
model_config=self.model_config,
)
result = await self.render_chat_request(request)
if isinstance(result, ErrorResponse):
return result
conversation, engine_inputs = result
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
lora_request = self._maybe_get_adapters(request, supports_default_mm_loras=True)
model_name = self.models.model_name(lora_request)
# Extract data_parallel_rank from header (router can inject it)
data_parallel_rank = self._get_data_parallel_rank(raw_request)
# Schedule the request and get the result generator.
max_model_len = self.model_config.max_model_len
generators: list[AsyncGenerator[RequestOutput, None]] = []
mm_token_counts: dict[str, int] | None = None
for i, engine_input in enumerate(engine_inputs):
prompt_token_ids = self._extract_prompt_components(engine_input).token_ids
mm_token_counts = _get_mm_token_counts(engine_input)
# If we are creating sub requests for multiple prompts, ensure that they
# have unique request ids.
sub_request_id = (
request_id if len(engine_inputs) == 1 else f"{request_id}_{i}"
)
max_tokens = get_max_tokens(
max_model_len,
request.max_completion_tokens
if request.max_completion_tokens is not None
else request.max_tokens,
self._extract_prompt_len(engine_input),
self.default_sampling_params,
self.override_max_tokens,
truncate_prompt_tokens=request.truncate_prompt_tokens,
)
sampling_params: SamplingParams | BeamSearchParams
if request.use_beam_search:
sampling_params = request.to_beam_search_params(
max_tokens, self.default_sampling_params
)
else:
sampling_params = request.to_sampling_params(
max_tokens,
self.default_sampling_params,
)
self._log_inputs(
sub_request_id,
engine_input,
params=sampling_params,
lora_request=lora_request,
)
trace_headers = (
None
if raw_request is None
else await self._get_trace_headers(raw_request.headers)
)
if isinstance(sampling_params, BeamSearchParams):
generator = self.beam_search(
prompt=engine_input,
request_id=sub_request_id,
params=sampling_params,
lora_request=lora_request,
trace_headers=trace_headers,
)
else:
if not request.include_reasoning:
reasoning_ended = True
elif request._grammar_from_tool_parser:
# The Mistral grammar already includes an optional
# `think?` rule that handles both reasoning and
# non-reasoning outputs.
reasoning_ended = True
elif parser is not None and parser.reasoning_parser is not None:
reasoning_ended = parser.is_reasoning_end(prompt_token_ids or [])
else:
reasoning_ended = None
generator = self.engine_client.generate(
engine_input,
sampling_params,
sub_request_id,
lora_request=lora_request,
trace_headers=trace_headers,
priority=request.priority,
data_parallel_rank=data_parallel_rank,
reasoning_ended=reasoning_ended,
reasoning_parser_kwargs={
"chat_template_kwargs": chat_template_kwargs,
}
if parser is not None and parser.reasoning_parser is not None
else None,
)
generators.append(generator)
assert len(generators) == 1
(result_generator,) = generators
if request.stream:
return self.chat_completion_stream_generator(
request,
result_generator,
request_id,
model_name,
conversation,
tokenizer,
request_metadata,
chat_template_kwargs=chat_template_kwargs,
mm_token_counts=mm_token_counts,
)
return await self.chat_completion_full_generator(
request,
result_generator,
request_id,
model_name,
conversation,
tokenizer,
request_metadata,
parser=parser,
mm_token_counts=mm_token_counts,
)
def get_chat_request_role(self, request: ChatCompletionRequest) -> str:
if request.add_generation_prompt:
return self.response_role
return request.messages[-1]["role"]
async def chat_completion_stream_generator(
self,
request: ChatCompletionRequest,
result_generator: AsyncIterator[RequestOutput],
request_id: str,
model_name: str,
conversation: list[ConversationMessage],
tokenizer: TokenizerLike,
request_metadata: RequestResponseMetadata,
chat_template_kwargs: dict[str, Any] | None = None,
mm_token_counts: dict[str, int] | None = None,
) -> AsyncGenerator[str, None]:
created_time = int(time.time())
chunk_object_type: Final = "chat.completion.chunk"
first_iteration = 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
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
previous_texts = [""] * num_choices
try:
if self.parser_cls is not None:
if tokenizer is None:
raise ValueError(
"Tokenizer not available when `skip_tokenizer_init=True`"
)
parsers: list[Parser | None] = [
self.parser_cls(
tokenizer,
request.tools,
chat_template_kwargs=chat_template_kwargs,
model_config=self.model_config,
)
for _ in range(num_choices)
]
else:
parsers = [None] * num_choices
except Exception as e:
logger.exception("Error in 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
)
last_res: RequestOutput | None = None
try:
async for res in result_generator:
last_res = res
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)
# 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:
num_cached_tokens = res.num_cached_tokens
# Send first response for each request.n (index) with
# the role
role = self.get_chat_request_role(request)
# ``res.prompt`` is the rendered chat-templated prompt
prompt_text = res.prompt if request.return_prompt_text else None
# 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 = ChatCompletionStreamResponse(
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
),
prompt_text=prompt_text,
)
# 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 = ChatCompletionStreamResponse(
id=request_id,
object=chunk_object_type,
created=created_time,
choices=[choice_data],
model=model_name,
)
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 = False
for output in res.outputs:
i = output.index
parser = 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
delta_text = output.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
if parser is not None:
delta_message = parser.parse_delta(
delta_text=delta_text,
delta_token_ids=as_list(output.token_ids),
request=request,
prompt_token_ids=res.prompt_token_ids,
finished=output.finish_reason is not None,
)
if delta_message is not None and delta_message.tool_calls:
tools_streamed[i] = True
# handle streaming just a content delta (no parsers)
else:
delta_message = DeltaMessage(content=delta_text)
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
# When reasoning is hidden, suppress per-token
# metadata (logprobs, token_ids) on every chunk to
# prevent leaking reasoning tokens through decoded
# token text in logprob entries or raw token IDs.
hide_stream_metadata = (
not request.include_reasoning and parser is not None
)
if hide_stream_metadata:
logprobs = None
if delta_message is None:
# NOTE: If return_token_ids is enabled, we still need to
# send a chunk with token_ids even if delta_message is None
# to ensure all tokens are included in the response
if output.finish_reason is None and (
not request.return_token_ids or hide_stream_metadata
):
continue
delta_message = DeltaMessage()
# Log streaming delta if output logging is enabled
if self.enable_log_outputs and self.request_logger:
delta_content_parts = []
if delta_message.content:
delta_content_parts.append(delta_message.content)
if delta_message.reasoning:
reasoning = delta_message.reasoning
delta_content_parts.append(f"[reasoning: {reasoning}]")
if delta_message.tool_calls:
tool_args = "".join(
tc.function.arguments
for tc in delta_message.tool_calls
if tc.function and tc.function.arguments
)
if tool_args:
delta_content_parts.append(f"[tool_calls: {tool_args}]")
if delta_content_parts and self.enable_log_deltas:
delta_content = " ".join(delta_content_parts)
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,
)
include_token_ids = (
request.return_token_ids and not hide_stream_metadata
)
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 include_token_ids else None
),
)
# if the model is finished generating
else:
# check for error finish reason and abort streaming
# finish_reason='error' indicates a retryable error
self._raise_if_error(output.finish_reason, request_id)
# 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 tools_streamed[i] and not tool_choice_function_name:
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 include_token_ids else None
),
)
finish_reason_sent[i] = True
choice_data = maybe_filter_parallel_tool_calls(choice_data, request)
chunk = ChatCompletionStreamResponse(
id=request_id,
object=chunk_object_type,
created=created_time,
choices=[choice_data],
model=model_name,
)
# Stamp the fingerprint on terminal chunks only (those with
# finish_reason set). When ``include_usage`` is on, the
# trailing usage chunk below overrides this as the true
# final message.
if (
not include_usage
and self.system_fingerprint is not None
and choice_data.finish_reason is not None
):
chunk.system_fingerprint = self.system_fingerprint
# 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"
# 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,
)
final_usage.prompt_tokens_details = _make_prompt_tokens_details(
self.enable_prompt_tokens_details,
num_cached_tokens,
mm_token_counts,
)
# In streaming, metrics ride on this final usage chunk, which is
# only emitted when usage reporting is enabled (i.e.
# ``stream_options.include_usage=true`` or
# ``--enable-force-include-usage``).
stream_per_request_metrics: PerRequestTimingMetrics | None = None
if (
self.enable_per_request_metrics
# See note in chat_completion_full_generator: suppress for n>1.
and (request.n or 1) == 1
):
last_metrics = last_res.metrics if last_res is not None else None
stream_per_request_metrics = build_per_request_timing_metrics(
last_metrics, completion_tokens
)
final_usage_chunk = ChatCompletionStreamResponse(
id=request_id,
object=chunk_object_type,
created=created_time,
choices=[],
model=model_name,
usage=final_usage,
system_fingerprint=self.system_fingerprint,
metrics=stream_per_request_metrics,
)
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"<streaming_complete: {previous_num_tokens[i]} tokens>"
)
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 GenerationError as e:
yield f"data: {self._convert_generation_error_to_streaming_response(e)}\n\n"
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,
parser: Parser | None = None,
mm_token_counts: dict[str, int] | None = None,
) -> ErrorResponse | ChatCompletionResponse:
created_time = int(time.time())
final_res: RequestOutput | None = None
try:
async for res in result_generator:
final_res = res
except asyncio.CancelledError:
return self.create_error_response("Client disconnected")
if final_res is None:
return self.create_error_response(
"No output received from the engine.",
err_type="InternalServerError",
status_code=HTTPStatus.INTERNAL_SERVER_ERROR,
)
choices: list[ChatCompletionResponseChoice] = []
role = self.get_chat_request_role(request)
tool_parser_cls = (
self.parser_cls.tool_parser_cls if self.parser_cls is not None else None
)
for output in final_res.outputs:
# check for error finish reason and raise GenerationError
# finish_reason='error' indicates a retryable request-level internal error
self._raise_if_error(output.finish_reason, request_id)
token_ids = output.token_ids
out_logprobs = output.logprobs
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 parser is not None:
reasoning, content, tool_calls = parser.parse(
output.text,
request,
enable_auto_tools=self.enable_auto_tools,
model_output_token_ids=token_ids,
)
suppress_metadata = not request.include_reasoning and parser is not None
if not request.include_reasoning:
reasoning = None
if suppress_metadata:
logprobs = None
else:
reasoning = None
content = output.text
tool_calls = []
suppress_metadata = False
auto_tools_called = False
is_named_tool_choice = (
request.tool_choice is not None
and type(request.tool_choice) is ChatCompletionNamedToolChoiceParam
)
is_required_tool_choice = request.tool_choice == "required"
if (not self.enable_auto_tools or not tool_parser_cls) and (
not is_named_tool_choice and not is_required_tool_choice
):
message = ChatMessage(role=role, reasoning=reasoning, content=content)
elif is_named_tool_choice or is_required_tool_choice:
message = ChatMessage(
role=role,
reasoning=reasoning,
content=content or "",
tool_calls=[
ToolCall(id=tc.id or make_tool_call_id(), function=tc)
for tc in (tool_calls or [])
],
)
# 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=reasoning, 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 tool_parser_cls
):
auto_tools_called = tool_calls is not None and len(tool_calls) > 0
if tool_calls:
message = ChatMessage(
role=role,
reasoning=reasoning,
content=content,
tool_calls=[
ToolCall(id=tc.id or make_tool_call_id(), function=tc)
for tc in tool_calls
],
)
else:
message = ChatMessage(
role=role,
reasoning=reasoning,
content=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=reasoning, content=content)
# 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.
is_finish_reason_tool_calls = auto_tools_called or (
request.tool_choice
and request.tool_choice == "required"
and output.finish_reason == "stop"
)
# Encode routed_experts for transport. JSON can't carry raw
# bytes, so we write the ndarray as a ``.npy`` byte stream
# and base64-encode it. ``pybase64`` is ~3x faster than the
# stdlib ``base64`` on large payloads thanks to SIMD.
routed_experts_b64 = None
if output.routed_experts is not None:
buf = io.BytesIO()
np.save(buf, output.routed_experts)
routed_experts_b64 = base64.b64encode(buf.getvalue()).decode("ascii")
choice_data = ChatCompletionResponseChoice(
index=output.index,
message=message,
logprobs=logprobs,
finish_reason="tool_calls"
if is_finish_reason_tool_calls
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 and not suppress_metadata
else None
),
routed_experts=routed_experts_b64,
)
choice_data = maybe_filter_parallel_tool_calls(choice_data, request)
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,
)
usage.prompt_tokens_details = _make_prompt_tokens_details(
self.enable_prompt_tokens_details,
final_res.num_cached_tokens,
mm_token_counts,
)
request_metadata.final_usage_info = usage
per_request_metrics: PerRequestTimingMetrics | None = None
if (
self.enable_per_request_metrics
# Timing metrics describe a single generation stream. For n>1 the
# returned stats belong to only one of the n sequences, so they
# cannot be accurately attributed to the request; suppress instead.
and (request.n or 1) == 1
):
per_request_metrics = build_per_request_timing_metrics(
final_res.metrics, num_generated_tokens
)
# ``final_res.prompt`` is the rendered chat-templated prompt text
prompt_text = final_res.prompt if request.return_prompt_text else None
response = ChatCompletionResponse(
id=request_id,
created=created_time,
model=model_name,
choices=choices,
usage=usage,
system_fingerprint=self.system_fingerprint,
prompt_logprobs=clamp_prompt_logprobs(final_res.prompt_logprobs),
prompt_token_ids=(
final_res.prompt_token_ids if request.return_token_ids else None
),
prompt_text=prompt_text,
kv_transfer_params=final_res.kv_transfer_params,
ec_transfer_params=final_res.ec_transfer_params,
metrics=per_request_metrics,
)
# 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: # type: ignore
function_call: FunctionCall = tc.function # type: ignore
tool_call_descriptions.append(
f"{function_call.name}({function_call.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 _get_top_logprobs(
self,
logprobs: dict[int, Logprob],
top_logprobs: int | None,
tokenizer: TokenizerLike | None,
should_return_as_token_id: bool,
) -> list[ChatCompletionLogProb]:
return [
ChatCompletionLogProb(
token=(
token := self._get_decoded_token(
p[1],
p[0],
tokenizer,
return_as_token_id=should_return_as_token_id,
)
),
logprob=max(p[1].logprob, -9999.0),
bytes=list(token.encode("utf-8", errors="replace")),
)
for i, p in enumerate(logprobs.items())
if (top_logprobs and i < top_logprobs or top_logprobs == -1)
]
def _create_chat_logprobs(
self,
token_ids: GenericSequence[int],
top_logprobs: GenericSequence[dict[int, Logprob] | None],
tokenizer: TokenizerLike | None,
num_output_top_logprobs: int | None = None,
return_as_token_id: bool | None = None,
) -> ChatCompletionLogProbs:
"""Create OpenAI-style logprobs."""
logprobs_content: list[ChatCompletionLogProbsContent] = []
should_return_as_token_id = (
return_as_token_id
if return_as_token_id is not None
else self.return_tokens_as_token_ids
)
for i, token_id in enumerate(token_ids):
step_top_logprobs = top_logprobs[i]
if step_top_logprobs is None or step_top_logprobs.get(token_id) is None:
if should_return_as_token_id:
token = format_token_id_placeholder(token_id)
else:
if tokenizer is None:
raise ValueError(
"Unable to get tokenizer because `skip_tokenizer_init=True`"
)
token = tokenizer.decode(token_id)
logprobs_content.append(
ChatCompletionLogProbsContent(
token=token,
bytes=list(token.encode("utf-8", errors="replace")),
)
)
else:
step_token = step_top_logprobs[token_id]
step_decoded = step_token.decoded_token
logprobs_content.append(
ChatCompletionLogProbsContent(
token=self._get_decoded_token(
step_token,
token_id,
tokenizer,
should_return_as_token_id,
),
logprob=max(step_token.logprob, -9999.0),
bytes=(
None
if step_decoded is None
else list(step_decoded.encode("utf-8", errors="replace"))
),
top_logprobs=self._get_top_logprobs(
step_top_logprobs,
num_output_top_logprobs,
tokenizer,
should_return_as_token_id,
),
)
)
return ChatCompletionLogProbs(content=logprobs_content)