llama-stack-mirror/llama_stack/providers/remote/inference/vllm/vllm.py
Matthew Farrellee 3d119a86d4
chore: indicate to mypy that InferenceProvider.batch_completion/batch_chat_completion is concrete (#3239)
# What does this PR do?

closes https://github.com/llamastack/llama-stack/issues/3236

mypy considered our default implementations (raise NotImplementedError)
to be trivial. the result was we implemented the same stubs in
providers.

this change puts enough into the default impls so mypy considers them
non-trivial. this allows us to remove the duplicate implementations.
2025-08-22 14:17:30 -07:00

713 lines
26 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
import json
from collections.abc import AsyncGenerator, AsyncIterator
from typing import Any
import httpx
from openai import APIConnectionError, AsyncOpenAI
from openai.types.chat.chat_completion_chunk import (
ChatCompletionChunk as OpenAIChatCompletionChunk,
)
from llama_stack.apis.common.content_types import (
InterleavedContent,
InterleavedContentItem,
TextDelta,
ToolCallDelta,
ToolCallParseStatus,
)
from llama_stack.apis.inference import (
ChatCompletionRequest,
ChatCompletionResponse,
ChatCompletionResponseEvent,
ChatCompletionResponseEventType,
ChatCompletionResponseStreamChunk,
CompletionMessage,
CompletionRequest,
CompletionResponse,
CompletionResponseStreamChunk,
EmbeddingsResponse,
EmbeddingTaskType,
GrammarResponseFormat,
Inference,
JsonSchemaResponseFormat,
LogProbConfig,
Message,
ModelStore,
OpenAIChatCompletion,
OpenAICompletion,
OpenAIEmbeddingData,
OpenAIEmbeddingsResponse,
OpenAIEmbeddingUsage,
OpenAIMessageParam,
OpenAIResponseFormatParam,
ResponseFormat,
SamplingParams,
TextTruncation,
ToolChoice,
ToolConfig,
ToolDefinition,
ToolPromptFormat,
)
from llama_stack.apis.models import Model, ModelType
from llama_stack.log import get_logger
from llama_stack.models.llama.datatypes import BuiltinTool, StopReason, ToolCall
from llama_stack.models.llama.sku_list import all_registered_models
from llama_stack.providers.datatypes import (
HealthResponse,
HealthStatus,
ModelsProtocolPrivate,
)
from llama_stack.providers.utils.inference.model_registry import (
ModelRegistryHelper,
build_hf_repo_model_entry,
)
from llama_stack.providers.utils.inference.openai_compat import (
UnparseableToolCall,
convert_message_to_openai_dict,
convert_tool_call,
get_sampling_options,
prepare_openai_completion_params,
process_chat_completion_stream_response,
process_completion_response,
process_completion_stream_response,
)
from llama_stack.providers.utils.inference.prompt_adapter import (
completion_request_to_prompt,
content_has_media,
interleaved_content_as_str,
request_has_media,
)
from .config import VLLMInferenceAdapterConfig
log = get_logger(name=__name__, category="inference::vllm")
def build_hf_repo_model_entries():
return [
build_hf_repo_model_entry(
model.huggingface_repo,
model.descriptor(),
)
for model in all_registered_models()
if model.huggingface_repo
]
def _convert_to_vllm_tool_calls_in_response(
tool_calls,
) -> list[ToolCall]:
if not tool_calls:
return []
return [
ToolCall(
call_id=call.id,
tool_name=call.function.name,
arguments=json.loads(call.function.arguments),
arguments_json=call.function.arguments,
)
for call in tool_calls
]
def _convert_to_vllm_tools_in_request(tools: list[ToolDefinition]) -> list[dict]:
compat_tools = []
for tool in tools:
properties = {}
compat_required = []
if tool.parameters:
for tool_key, tool_param in tool.parameters.items():
properties[tool_key] = {"type": tool_param.param_type}
if tool_param.description:
properties[tool_key]["description"] = tool_param.description
if tool_param.default:
properties[tool_key]["default"] = tool_param.default
if tool_param.required:
compat_required.append(tool_key)
# The tool.tool_name can be a str or a BuiltinTool enum. If
# it's the latter, convert to a string.
tool_name = tool.tool_name
if isinstance(tool_name, BuiltinTool):
tool_name = tool_name.value
compat_tool = {
"type": "function",
"function": {
"name": tool_name,
"description": tool.description,
"parameters": {
"type": "object",
"properties": properties,
"required": compat_required,
},
},
}
compat_tools.append(compat_tool)
return compat_tools
def _convert_to_vllm_finish_reason(finish_reason: str) -> StopReason:
return {
"stop": StopReason.end_of_turn,
"length": StopReason.out_of_tokens,
"tool_calls": StopReason.end_of_message,
}.get(finish_reason, StopReason.end_of_turn)
def _process_vllm_chat_completion_end_of_stream(
finish_reason: str | None,
last_chunk_content: str | None,
current_event_type: ChatCompletionResponseEventType,
tool_call_bufs: dict[str, UnparseableToolCall] | None = None,
) -> list[OpenAIChatCompletionChunk]:
chunks = []
if finish_reason is not None:
stop_reason = _convert_to_vllm_finish_reason(finish_reason)
else:
stop_reason = StopReason.end_of_message
tool_call_bufs = tool_call_bufs or {}
for _index, tool_call_buf in sorted(tool_call_bufs.items()):
args_str = tool_call_buf.arguments or "{}"
try:
args = json.loads(args_str)
chunks.append(
ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=current_event_type,
delta=ToolCallDelta(
tool_call=ToolCall(
call_id=tool_call_buf.call_id,
tool_name=tool_call_buf.tool_name,
arguments=args,
arguments_json=args_str,
),
parse_status=ToolCallParseStatus.succeeded,
),
)
)
)
except Exception as e:
log.warning(f"Failed to parse tool call buffer arguments: {args_str} \nError: {e}")
chunks.append(
ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call=str(tool_call_buf),
parse_status=ToolCallParseStatus.failed,
),
)
)
)
chunks.append(
ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.complete,
delta=TextDelta(text=last_chunk_content or ""),
logprobs=None,
stop_reason=stop_reason,
)
)
)
return chunks
async def _process_vllm_chat_completion_stream_response(
stream: AsyncGenerator[OpenAIChatCompletionChunk, None],
) -> AsyncGenerator:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.start,
delta=TextDelta(text=""),
)
)
event_type = ChatCompletionResponseEventType.progress
tool_call_bufs: dict[str, UnparseableToolCall] = {}
end_of_stream_processed = False
async for chunk in stream:
if not chunk.choices:
log.warning("vLLM failed to generation any completions - check the vLLM server logs for an error.")
return
choice = chunk.choices[0]
if choice.delta.tool_calls:
for delta_tool_call in choice.delta.tool_calls:
tool_call = convert_tool_call(delta_tool_call)
if delta_tool_call.index not in tool_call_bufs:
tool_call_bufs[delta_tool_call.index] = UnparseableToolCall()
tool_call_buf = tool_call_bufs[delta_tool_call.index]
tool_call_buf.tool_name += str(tool_call.tool_name)
tool_call_buf.call_id += tool_call.call_id
tool_call_buf.arguments += (
tool_call.arguments if isinstance(tool_call.arguments, str) else json.dumps(tool_call.arguments)
)
if choice.finish_reason:
chunks = _process_vllm_chat_completion_end_of_stream(
finish_reason=choice.finish_reason,
last_chunk_content=choice.delta.content,
current_event_type=event_type,
tool_call_bufs=tool_call_bufs,
)
for c in chunks:
yield c
end_of_stream_processed = True
elif not choice.delta.tool_calls:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=event_type,
delta=TextDelta(text=choice.delta.content or ""),
logprobs=None,
)
)
event_type = ChatCompletionResponseEventType.progress
if end_of_stream_processed:
return
# the stream ended without a chunk containing finish_reason - we have to generate the
# respective completion chunks manually
chunks = _process_vllm_chat_completion_end_of_stream(
finish_reason=None, last_chunk_content=None, current_event_type=event_type, tool_call_bufs=tool_call_bufs
)
for c in chunks:
yield c
class VLLMInferenceAdapter(Inference, ModelsProtocolPrivate):
# automatically set by the resolver when instantiating the provider
__provider_id__: str
model_store: ModelStore | None = None
def __init__(self, config: VLLMInferenceAdapterConfig) -> None:
self.register_helper = ModelRegistryHelper(build_hf_repo_model_entries())
self.config = config
self.client = None
async def initialize(self) -> None:
if not self.config.url:
raise ValueError(
"You must provide a URL in run.yaml (or via the VLLM_URL environment variable) to use vLLM."
)
async def should_refresh_models(self) -> bool:
return self.config.refresh_models
async def list_models(self) -> list[Model] | None:
self._lazy_initialize_client()
assert self.client is not None # mypy
models = []
async for m in self.client.models.list():
model_type = ModelType.llm # unclear how to determine embedding vs. llm models
models.append(
Model(
identifier=m.id,
provider_resource_id=m.id,
provider_id=self.__provider_id__,
metadata={},
model_type=model_type,
)
)
return models
async def shutdown(self) -> None:
pass
async def unregister_model(self, model_id: str) -> None:
pass
async def health(self) -> HealthResponse:
"""
Performs a health check by verifying connectivity to the remote vLLM server.
This method is used by the Provider API to verify
that the service is running correctly.
Returns:
HealthResponse: A dictionary containing the health status.
"""
try:
client = self._create_client() if self.client is None else self.client
_ = [m async for m in client.models.list()] # Ensure the client is initialized
return HealthResponse(status=HealthStatus.OK)
except Exception as e:
return HealthResponse(status=HealthStatus.ERROR, message=f"Health check failed: {str(e)}")
async def _get_model(self, model_id: str) -> Model:
if not self.model_store:
raise ValueError("Model store not set")
return await self.model_store.get_model(model_id)
def _lazy_initialize_client(self):
if self.client is not None:
return
log.info(f"Initializing vLLM client with base_url={self.config.url}")
self.client = self._create_client()
def _create_client(self):
return AsyncOpenAI(
base_url=self.config.url,
api_key=self.config.api_token,
http_client=httpx.AsyncClient(verify=self.config.tls_verify),
)
async def completion(
self,
model_id: str,
content: InterleavedContent,
sampling_params: SamplingParams | None = None,
response_format: ResponseFormat | None = None,
stream: bool | None = False,
logprobs: LogProbConfig | None = None,
) -> CompletionResponse | AsyncGenerator[CompletionResponseStreamChunk, None]:
self._lazy_initialize_client()
if sampling_params is None:
sampling_params = SamplingParams()
model = await self._get_model(model_id)
if model.provider_resource_id is None:
raise ValueError(f"Model {model_id} has no provider_resource_id set")
request = CompletionRequest(
model=model.provider_resource_id,
content=content,
sampling_params=sampling_params,
response_format=response_format,
stream=stream,
logprobs=logprobs,
)
if stream:
return self._stream_completion(request)
else:
return await self._nonstream_completion(request)
async def chat_completion(
self,
model_id: str,
messages: list[Message],
sampling_params: SamplingParams | None = None,
tools: list[ToolDefinition] | None = None,
tool_choice: ToolChoice | None = ToolChoice.auto,
tool_prompt_format: ToolPromptFormat | None = None,
response_format: ResponseFormat | None = None,
stream: bool | None = False,
logprobs: LogProbConfig | None = None,
tool_config: ToolConfig | None = None,
) -> ChatCompletionResponse | AsyncGenerator[ChatCompletionResponseStreamChunk, None]:
self._lazy_initialize_client()
if sampling_params is None:
sampling_params = SamplingParams()
model = await self._get_model(model_id)
if model.provider_resource_id is None:
raise ValueError(f"Model {model_id} has no provider_resource_id set")
# This is to be consistent with OpenAI API and support vLLM <= v0.6.3
# References:
# * https://platform.openai.com/docs/api-reference/chat/create#chat-create-tool_choice
# * https://github.com/vllm-project/vllm/pull/10000
if not tools and tool_config is not None:
tool_config.tool_choice = ToolChoice.none
request = ChatCompletionRequest(
model=model.provider_resource_id,
messages=messages,
sampling_params=sampling_params,
tools=tools or [],
stream=stream,
logprobs=logprobs,
response_format=response_format,
tool_config=tool_config,
)
if stream:
return self._stream_chat_completion(request, self.client)
else:
return await self._nonstream_chat_completion(request, self.client)
async def _nonstream_chat_completion(
self, request: ChatCompletionRequest, client: AsyncOpenAI
) -> ChatCompletionResponse:
params = await self._get_params(request)
r = await client.chat.completions.create(**params)
choice = r.choices[0]
result = ChatCompletionResponse(
completion_message=CompletionMessage(
content=choice.message.content or "",
stop_reason=_convert_to_vllm_finish_reason(choice.finish_reason),
tool_calls=_convert_to_vllm_tool_calls_in_response(choice.message.tool_calls),
),
logprobs=None,
)
return result
async def _stream_chat_completion(
self, request: ChatCompletionRequest, client: AsyncOpenAI
) -> AsyncGenerator[ChatCompletionResponseStreamChunk, None]:
params = await self._get_params(request)
stream = await client.chat.completions.create(**params)
if request.tools:
res = _process_vllm_chat_completion_stream_response(stream)
else:
res = process_chat_completion_stream_response(stream, request)
async for chunk in res:
yield chunk
async def _nonstream_completion(self, request: CompletionRequest) -> CompletionResponse:
assert self.client is not None
params = await self._get_params(request)
r = await self.client.completions.create(**params)
return process_completion_response(r)
async def _stream_completion(
self, request: CompletionRequest
) -> AsyncGenerator[CompletionResponseStreamChunk, None]:
assert self.client is not None
params = await self._get_params(request)
stream = await self.client.completions.create(**params)
async for chunk in process_completion_stream_response(stream):
yield chunk
async def register_model(self, model: Model) -> Model:
# register_model is called during Llama Stack initialization, hence we cannot init self.client if not initialized yet.
# self.client should only be created after the initialization is complete to avoid asyncio cross-context errors.
# Changing this may lead to unpredictable behavior.
client = self._create_client() if self.client is None else self.client
try:
model = await self.register_helper.register_model(model)
except ValueError:
pass # Ignore statically unknown model, will check live listing
try:
res = await client.models.list()
except APIConnectionError as e:
raise ValueError(
f"Failed to connect to vLLM at {self.config.url}. Please check if vLLM is running and accessible at that URL."
) from e
available_models = [m.id async for m in res]
if model.provider_resource_id not in available_models:
raise ValueError(
f"Model {model.provider_resource_id} is not being served by vLLM. "
f"Available models: {', '.join(available_models)}"
)
return model
async def _get_params(self, request: ChatCompletionRequest | CompletionRequest) -> dict:
options = get_sampling_options(request.sampling_params)
if "max_tokens" not in options:
options["max_tokens"] = self.config.max_tokens
input_dict: dict[str, Any] = {}
# Only include the 'tools' param if there is any. It can break things if an empty list is sent to the vLLM.
if isinstance(request, ChatCompletionRequest) and request.tools:
input_dict = {"tools": _convert_to_vllm_tools_in_request(request.tools)}
if isinstance(request, ChatCompletionRequest):
input_dict["messages"] = [await convert_message_to_openai_dict(m, download=True) for m in request.messages]
else:
assert not request_has_media(request), "vLLM does not support media for Completion requests"
input_dict["prompt"] = await completion_request_to_prompt(request)
if fmt := request.response_format:
if isinstance(fmt, JsonSchemaResponseFormat):
input_dict["extra_body"] = {"guided_json": fmt.json_schema}
elif isinstance(fmt, GrammarResponseFormat):
raise NotImplementedError("Grammar response format not supported yet")
else:
raise ValueError(f"Unknown response format {fmt.type}")
if request.logprobs and request.logprobs.top_k:
input_dict["logprobs"] = request.logprobs.top_k
return {
"model": request.model,
**input_dict,
"stream": request.stream,
**options,
}
async def embeddings(
self,
model_id: str,
contents: list[str] | list[InterleavedContentItem],
text_truncation: TextTruncation | None = TextTruncation.none,
output_dimension: int | None = None,
task_type: EmbeddingTaskType | None = None,
) -> EmbeddingsResponse:
self._lazy_initialize_client()
assert self.client is not None
model = await self._get_model(model_id)
kwargs = {}
assert model.model_type == ModelType.embedding
assert model.metadata.get("embedding_dimension")
kwargs["dimensions"] = model.metadata.get("embedding_dimension")
assert all(not content_has_media(content) for content in contents), "VLLM does not support media for embeddings"
response = await self.client.embeddings.create(
model=model.provider_resource_id,
input=[interleaved_content_as_str(content) for content in contents],
**kwargs,
)
embeddings = [data.embedding for data in response.data]
return EmbeddingsResponse(embeddings=embeddings)
async def openai_embeddings(
self,
model: str,
input: str | list[str],
encoding_format: str | None = "float",
dimensions: int | None = None,
user: str | None = None,
) -> OpenAIEmbeddingsResponse:
self._lazy_initialize_client()
assert self.client is not None
model_obj = await self._get_model(model)
assert model_obj.model_type == ModelType.embedding
# Convert input to list if it's a string
input_list = [input] if isinstance(input, str) else input
# Call vLLM embeddings endpoint with encoding_format
response = await self.client.embeddings.create(
model=model_obj.provider_resource_id,
input=input_list,
dimensions=dimensions,
encoding_format=encoding_format,
)
# Convert response to OpenAI format
data = [
OpenAIEmbeddingData(
embedding=embedding_data.embedding,
index=i,
)
for i, embedding_data in enumerate(response.data)
]
# Not returning actual token usage since vLLM doesn't provide it
usage = OpenAIEmbeddingUsage(prompt_tokens=-1, total_tokens=-1)
return OpenAIEmbeddingsResponse(
data=data,
model=model_obj.provider_resource_id,
usage=usage,
)
async def openai_completion(
self,
model: str,
prompt: str | list[str] | list[int] | list[list[int]],
best_of: int | None = None,
echo: bool | None = None,
frequency_penalty: float | None = None,
logit_bias: dict[str, float] | None = None,
logprobs: bool | None = None,
max_tokens: int | None = None,
n: int | None = None,
presence_penalty: float | None = None,
seed: int | None = None,
stop: str | list[str] | None = None,
stream: bool | None = None,
stream_options: dict[str, Any] | None = None,
temperature: float | None = None,
top_p: float | None = None,
user: str | None = None,
guided_choice: list[str] | None = None,
prompt_logprobs: int | None = None,
suffix: str | None = None,
) -> OpenAICompletion:
self._lazy_initialize_client()
model_obj = await self._get_model(model)
extra_body: dict[str, Any] = {}
if prompt_logprobs is not None and prompt_logprobs >= 0:
extra_body["prompt_logprobs"] = prompt_logprobs
if guided_choice:
extra_body["guided_choice"] = guided_choice
params = await prepare_openai_completion_params(
model=model_obj.provider_resource_id,
prompt=prompt,
best_of=best_of,
echo=echo,
frequency_penalty=frequency_penalty,
logit_bias=logit_bias,
logprobs=logprobs,
max_tokens=max_tokens,
n=n,
presence_penalty=presence_penalty,
seed=seed,
stop=stop,
stream=stream,
stream_options=stream_options,
temperature=temperature,
top_p=top_p,
user=user,
extra_body=extra_body,
)
return await self.client.completions.create(**params) # type: ignore
async def openai_chat_completion(
self,
model: str,
messages: list[OpenAIMessageParam],
frequency_penalty: float | None = None,
function_call: str | dict[str, Any] | None = None,
functions: list[dict[str, Any]] | None = None,
logit_bias: dict[str, float] | None = None,
logprobs: bool | None = None,
max_completion_tokens: int | None = None,
max_tokens: int | None = None,
n: int | None = None,
parallel_tool_calls: bool | None = None,
presence_penalty: float | None = None,
response_format: OpenAIResponseFormatParam | None = None,
seed: int | None = None,
stop: str | list[str] | None = None,
stream: bool | None = None,
stream_options: dict[str, Any] | None = None,
temperature: float | None = None,
tool_choice: str | dict[str, Any] | None = None,
tools: list[dict[str, Any]] | None = None,
top_logprobs: int | None = None,
top_p: float | None = None,
user: str | None = None,
) -> OpenAIChatCompletion | AsyncIterator[OpenAIChatCompletionChunk]:
self._lazy_initialize_client()
model_obj = await self._get_model(model)
params = await prepare_openai_completion_params(
model=model_obj.provider_resource_id,
messages=messages,
frequency_penalty=frequency_penalty,
function_call=function_call,
functions=functions,
logit_bias=logit_bias,
logprobs=logprobs,
max_completion_tokens=max_completion_tokens,
max_tokens=max_tokens,
n=n,
parallel_tool_calls=parallel_tool_calls,
presence_penalty=presence_penalty,
response_format=response_format,
seed=seed,
stop=stop,
stream=stream,
stream_options=stream_options,
temperature=temperature,
tool_choice=tool_choice,
tools=tools,
top_logprobs=top_logprobs,
top_p=top_p,
user=user,
)
return await self.client.chat.completions.create(**params) # type: ignore