llama-stack-mirror/llama_stack/providers/utils/inference/openai_compat.py
Ben Browning 2b2db5fbda
feat: OpenAI-Compatible models, completions, chat/completions (#1894)
# What does this PR do?

This stubs in some OpenAI server-side compatibility with three new
endpoints:

/v1/openai/v1/models
/v1/openai/v1/completions
/v1/openai/v1/chat/completions

This gives common inference apps using OpenAI clients the ability to
talk to Llama Stack using an endpoint like
http://localhost:8321/v1/openai/v1 .

The two "v1" instances in there isn't awesome, but the thinking is that
Llama Stack's API is v1 and then our OpenAI compatibility layer is
compatible with OpenAI V1. And, some OpenAI clients implicitly assume
the URL ends with "v1", so this gives maximum compatibility.

The openai models endpoint is implemented in the routing layer, and just
returns all the models Llama Stack knows about.

The following providers should be working with the new OpenAI
completions and chat/completions API:
* remote::anthropic (untested)
* remote::cerebras-openai-compat (untested)
* remote::fireworks (tested)
* remote::fireworks-openai-compat (untested)
* remote::gemini (untested)
* remote::groq-openai-compat (untested)
* remote::nvidia (tested)
* remote::ollama (tested)
* remote::openai (untested)
* remote::passthrough (untested)
* remote::sambanova-openai-compat (untested)
* remote::together (tested)
* remote::together-openai-compat (untested)
* remote::vllm (tested)

The goal to support this for every inference provider - proxying
directly to the provider's OpenAI endpoint for OpenAI-compatible
providers. For providers that don't have an OpenAI-compatible API, we'll
add a mixin to translate incoming OpenAI requests to Llama Stack
inference requests and translate the Llama Stack inference responses to
OpenAI responses.

This is related to #1817 but is a bit larger in scope than just chat
completions, as I have real use-cases that need the older completions
API as well.

## Test Plan

### vLLM

```
VLLM_URL="http://localhost:8000/v1" INFERENCE_MODEL="meta-llama/Llama-3.2-3B-Instruct" llama stack build --template remote-vllm --image-type venv --run

LLAMA_STACK_CONFIG=http://localhost:8321 INFERENCE_MODEL="meta-llama/Llama-3.2-3B-Instruct" python -m pytest -v tests/integration/inference/test_openai_completion.py --text-model "meta-llama/Llama-3.2-3B-Instruct"
```

### ollama
```
INFERENCE_MODEL="llama3.2:3b-instruct-q8_0" llama stack build --template ollama --image-type venv --run

LLAMA_STACK_CONFIG=http://localhost:8321 INFERENCE_MODEL="llama3.2:3b-instruct-q8_0" python -m pytest -v tests/integration/inference/test_openai_completion.py --text-model "llama3.2:3b-instruct-q8_0"
```



## Documentation

Run a Llama Stack distribution that uses one of the providers mentioned
in the list above. Then, use your favorite OpenAI client to send
completion or chat completion requests with the base_url set to
http://localhost:8321/v1/openai/v1 . Replace "localhost:8321" with the
host and port of your Llama Stack server, if different.

---------

Signed-off-by: Ben Browning <bbrownin@redhat.com>
2025-04-11 13:14:17 -07:00

1182 lines
40 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
import logging
import time
import uuid
import warnings
from typing import Any, AsyncGenerator, Dict, Iterable, List, Optional, Union
from openai import AsyncStream
from openai.types.chat import (
ChatCompletionAssistantMessageParam as OpenAIChatCompletionAssistantMessage,
)
from openai.types.chat import (
ChatCompletionChunk as OpenAIChatCompletionChunk,
)
from openai.types.chat import (
ChatCompletionContentPartImageParam as OpenAIChatCompletionContentPartImageParam,
)
from openai.types.chat import (
ChatCompletionContentPartParam as OpenAIChatCompletionContentPartParam,
)
from openai.types.chat import (
ChatCompletionContentPartTextParam as OpenAIChatCompletionContentPartTextParam,
)
from openai.types.chat import (
ChatCompletionMessageParam as OpenAIChatCompletionMessage,
)
from openai.types.chat import (
ChatCompletionMessageToolCall,
)
from openai.types.chat import (
ChatCompletionMessageToolCallParam as OpenAIChatCompletionMessageToolCall,
)
from openai.types.chat import (
ChatCompletionSystemMessageParam as OpenAIChatCompletionSystemMessage,
)
from openai.types.chat import (
ChatCompletionToolMessageParam as OpenAIChatCompletionToolMessage,
)
from openai.types.chat import (
ChatCompletionUserMessageParam as OpenAIChatCompletionUserMessage,
)
from openai.types.chat.chat_completion import (
Choice as OpenAIChoice,
)
from openai.types.chat.chat_completion import (
ChoiceLogprobs as OpenAIChoiceLogprobs, # same as chat_completion_chunk ChoiceLogprobs
)
from openai.types.chat.chat_completion_content_part_image_param import (
ImageURL as OpenAIImageURL,
)
from openai.types.chat.chat_completion_message_tool_call_param import (
Function as OpenAIFunction,
)
from pydantic import BaseModel
from llama_stack.apis.common.content_types import (
ImageContentItem,
InterleavedContent,
TextContentItem,
TextDelta,
ToolCallDelta,
ToolCallParseStatus,
)
from llama_stack.apis.inference import (
ChatCompletionRequest,
ChatCompletionResponse,
ChatCompletionResponseEvent,
ChatCompletionResponseEventType,
ChatCompletionResponseStreamChunk,
CompletionMessage,
CompletionResponse,
CompletionResponseStreamChunk,
GreedySamplingStrategy,
Message,
SamplingParams,
SystemMessage,
TokenLogProbs,
ToolResponseMessage,
TopKSamplingStrategy,
TopPSamplingStrategy,
UserMessage,
)
from llama_stack.apis.inference.inference import OpenAIChatCompletion, OpenAICompletion, OpenAICompletionChoice
from llama_stack.models.llama.datatypes import (
BuiltinTool,
StopReason,
ToolCall,
ToolDefinition,
)
from llama_stack.providers.utils.inference.prompt_adapter import (
convert_image_content_to_url,
decode_assistant_message,
)
logger = logging.getLogger(__name__)
class OpenAICompatCompletionChoiceDelta(BaseModel):
content: str
class OpenAICompatLogprobs(BaseModel):
text_offset: Optional[List[int]] = None
token_logprobs: Optional[List[float]] = None
tokens: Optional[List[str]] = None
top_logprobs: Optional[List[Dict[str, float]]] = None
class OpenAICompatCompletionChoice(BaseModel):
finish_reason: Optional[str] = None
text: Optional[str] = None
delta: Optional[OpenAICompatCompletionChoiceDelta] = None
logprobs: Optional[OpenAICompatLogprobs] = None
class OpenAICompatCompletionResponse(BaseModel):
choices: List[OpenAICompatCompletionChoice]
def get_sampling_strategy_options(params: SamplingParams) -> dict:
options = {}
if isinstance(params.strategy, GreedySamplingStrategy):
options["temperature"] = 0.0
elif isinstance(params.strategy, TopPSamplingStrategy):
options["temperature"] = params.strategy.temperature
options["top_p"] = params.strategy.top_p
elif isinstance(params.strategy, TopKSamplingStrategy):
options["top_k"] = params.strategy.top_k
else:
raise ValueError(f"Unsupported sampling strategy: {params.strategy}")
return options
def get_sampling_options(params: SamplingParams | None) -> dict:
if not params:
return {}
options = {}
if params:
options.update(get_sampling_strategy_options(params))
if params.max_tokens:
options["max_tokens"] = params.max_tokens
if params.repetition_penalty is not None and params.repetition_penalty != 1.0:
options["repeat_penalty"] = params.repetition_penalty
if params.stop is not None:
options["stop"] = params.stop
return options
def text_from_choice(choice) -> str:
if hasattr(choice, "delta") and choice.delta:
return choice.delta.content
if hasattr(choice, "message"):
return choice.message.content
return choice.text
def get_stop_reason(finish_reason: str) -> StopReason:
if finish_reason in ["stop", "eos"]:
return StopReason.end_of_turn
elif finish_reason == "eom":
return StopReason.end_of_message
elif finish_reason == "length":
return StopReason.out_of_tokens
return StopReason.out_of_tokens
def convert_openai_completion_logprobs(
logprobs: Optional[OpenAICompatLogprobs],
) -> Optional[List[TokenLogProbs]]:
if not logprobs:
return None
if hasattr(logprobs, "top_logprobs"):
return [TokenLogProbs(logprobs_by_token=x) for x in logprobs.top_logprobs]
# Together supports logprobs with top_k=1 only. This means for each token position,
# they return only the logprobs for the selected token (vs. the top n most likely tokens).
# Here we construct the response by matching the selected token with the logprobs.
if logprobs.tokens and logprobs.token_logprobs:
return [
TokenLogProbs(logprobs_by_token={token: token_lp})
for token, token_lp in zip(logprobs.tokens, logprobs.token_logprobs, strict=False)
]
return None
def convert_openai_completion_logprobs_stream(text: str, logprobs: Optional[Union[float, OpenAICompatLogprobs]]):
if logprobs is None:
return None
if isinstance(logprobs, float):
# Adapt response from Together CompletionChoicesChunk
return [TokenLogProbs(logprobs_by_token={text: logprobs})]
if hasattr(logprobs, "top_logprobs"):
return [TokenLogProbs(logprobs_by_token=x) for x in logprobs.top_logprobs]
return None
def process_completion_response(
response: OpenAICompatCompletionResponse,
) -> CompletionResponse:
choice = response.choices[0]
# drop suffix <eot_id> if present and return stop reason as end of turn
if choice.text.endswith("<|eot_id|>"):
return CompletionResponse(
stop_reason=StopReason.end_of_turn,
content=choice.text[: -len("<|eot_id|>")],
logprobs=convert_openai_completion_logprobs(choice.logprobs),
)
# drop suffix <eom_id> if present and return stop reason as end of message
if choice.text.endswith("<|eom_id|>"):
return CompletionResponse(
stop_reason=StopReason.end_of_message,
content=choice.text[: -len("<|eom_id|>")],
logprobs=convert_openai_completion_logprobs(choice.logprobs),
)
return CompletionResponse(
stop_reason=get_stop_reason(choice.finish_reason),
content=choice.text,
logprobs=convert_openai_completion_logprobs(choice.logprobs),
)
def process_chat_completion_response(
response: OpenAICompatCompletionResponse,
request: ChatCompletionRequest,
) -> ChatCompletionResponse:
choice = response.choices[0]
if choice.finish_reason == "tool_calls":
if not choice.message or not choice.message.tool_calls:
raise ValueError("Tool calls are not present in the response")
tool_calls = [convert_tool_call(tool_call) for tool_call in choice.message.tool_calls]
if any(isinstance(tool_call, UnparseableToolCall) for tool_call in tool_calls):
# If we couldn't parse a tool call, jsonify the tool calls and return them
return ChatCompletionResponse(
completion_message=CompletionMessage(
stop_reason=StopReason.end_of_turn,
content=json.dumps(tool_calls, default=lambda x: x.model_dump()),
),
logprobs=None,
)
else:
# Otherwise, return tool calls as normal
return ChatCompletionResponse(
completion_message=CompletionMessage(
tool_calls=tool_calls,
stop_reason=StopReason.end_of_turn,
# Content is not optional
content="",
),
logprobs=None,
)
# TODO: This does not work well with tool calls for vLLM remote provider
# Ref: https://github.com/meta-llama/llama-stack/issues/1058
raw_message = decode_assistant_message(text_from_choice(choice), get_stop_reason(choice.finish_reason))
# NOTE: If we do not set tools in chat-completion request, we should not
# expect the ToolCall in the response. Instead, we should return the raw
# response from the model.
if raw_message.tool_calls:
if not request.tools:
raw_message.tool_calls = []
raw_message.content = text_from_choice(choice)
else:
# only return tool_calls if provided in the request
new_tool_calls = []
request_tools = {t.tool_name: t for t in request.tools}
for t in raw_message.tool_calls:
if t.tool_name in request_tools:
new_tool_calls.append(t)
else:
logger.warning(f"Tool {t.tool_name} not found in request tools")
if len(new_tool_calls) < len(raw_message.tool_calls):
raw_message.tool_calls = new_tool_calls
raw_message.content = text_from_choice(choice)
return ChatCompletionResponse(
completion_message=CompletionMessage(
content=raw_message.content,
stop_reason=raw_message.stop_reason,
tool_calls=raw_message.tool_calls,
),
logprobs=None,
)
async def process_completion_stream_response(
stream: AsyncGenerator[OpenAICompatCompletionResponse, None],
) -> AsyncGenerator[CompletionResponseStreamChunk, None]:
stop_reason = None
async for chunk in stream:
choice = chunk.choices[0]
finish_reason = choice.finish_reason
text = text_from_choice(choice)
if text == "<|eot_id|>":
stop_reason = StopReason.end_of_turn
text = ""
continue
elif text == "<|eom_id|>":
stop_reason = StopReason.end_of_message
text = ""
continue
yield CompletionResponseStreamChunk(
delta=text,
stop_reason=stop_reason,
logprobs=convert_openai_completion_logprobs_stream(text, choice.logprobs),
)
if finish_reason:
if finish_reason in ["stop", "eos", "eos_token"]:
stop_reason = StopReason.end_of_turn
elif finish_reason == "length":
stop_reason = StopReason.out_of_tokens
break
yield CompletionResponseStreamChunk(
delta="",
stop_reason=stop_reason,
)
async def process_chat_completion_stream_response(
stream: AsyncGenerator[OpenAICompatCompletionResponse, None],
request: ChatCompletionRequest,
) -> AsyncGenerator[ChatCompletionResponseStreamChunk, None]:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.start,
delta=TextDelta(text=""),
)
)
buffer = ""
ipython = False
stop_reason = None
async for chunk in stream:
choice = chunk.choices[0]
finish_reason = choice.finish_reason
if finish_reason:
if stop_reason is None and finish_reason in ["stop", "eos", "eos_token"]:
stop_reason = StopReason.end_of_turn
elif stop_reason is None and finish_reason == "length":
stop_reason = StopReason.out_of_tokens
break
text = text_from_choice(choice)
if not text:
# Sometimes you get empty chunks from providers
continue
# check if its a tool call ( aka starts with <|python_tag|> )
if not ipython and text.startswith("<|python_tag|>"):
ipython = True
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call="",
parse_status=ToolCallParseStatus.started,
),
)
)
buffer += text
continue
if text == "<|eot_id|>":
stop_reason = StopReason.end_of_turn
text = ""
continue
elif text == "<|eom_id|>":
stop_reason = StopReason.end_of_message
text = ""
continue
if ipython:
buffer += text
delta = ToolCallDelta(
tool_call=text,
parse_status=ToolCallParseStatus.in_progress,
)
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=delta,
stop_reason=stop_reason,
)
)
else:
buffer += text
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=TextDelta(text=text),
stop_reason=stop_reason,
)
)
# parse tool calls and report errors
message = decode_assistant_message(buffer, stop_reason)
parsed_tool_calls = len(message.tool_calls) > 0
if ipython and not parsed_tool_calls:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call="",
parse_status=ToolCallParseStatus.failed,
),
stop_reason=stop_reason,
)
)
request_tools = {t.tool_name: t for t in request.tools}
for tool_call in message.tool_calls:
if tool_call.tool_name in request_tools:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call=tool_call,
parse_status=ToolCallParseStatus.succeeded,
),
stop_reason=stop_reason,
)
)
else:
logger.warning(f"Tool {tool_call.tool_name} not found in request tools")
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
# Parsing tool call failed due to tool call not being found in request tools,
# We still add the raw message text inside tool_call for responding back to the user
tool_call=buffer,
parse_status=ToolCallParseStatus.failed,
),
stop_reason=stop_reason,
)
)
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.complete,
delta=TextDelta(text=""),
stop_reason=stop_reason,
)
)
async def convert_message_to_openai_dict(message: Message, download: bool = False) -> dict:
async def _convert_content(content) -> dict:
if isinstance(content, ImageContentItem):
return {
"type": "image_url",
"image_url": {
"url": await convert_image_content_to_url(content, download=download),
},
}
else:
text = content.text if isinstance(content, TextContentItem) else content
assert isinstance(text, str)
return {"type": "text", "text": text}
if isinstance(message.content, list):
content = [await _convert_content(c) for c in message.content]
else:
content = [await _convert_content(message.content)]
return {
"role": message.role,
"content": content,
}
class UnparseableToolCall(BaseModel):
"""
A ToolCall with arguments that are not valid JSON.
Mirrors the ToolCall schema, but with arguments as a string.
"""
call_id: str = ""
tool_name: str = ""
arguments: str = ""
async def convert_message_to_openai_dict_new(
message: Message | Dict,
) -> OpenAIChatCompletionMessage:
"""
Convert a Message to an OpenAI API-compatible dictionary.
"""
# users can supply a dict instead of a Message object, we'll
# convert it to a Message object and proceed with some type safety.
if isinstance(message, dict):
if "role" not in message:
raise ValueError("role is required in message")
if message["role"] == "user":
message = UserMessage(**message)
elif message["role"] == "assistant":
message = CompletionMessage(**message)
elif message["role"] == "tool":
message = ToolResponseMessage(**message)
elif message["role"] == "system":
message = SystemMessage(**message)
else:
raise ValueError(f"Unsupported message role: {message['role']}")
# Map Llama Stack spec to OpenAI spec -
# str -> str
# {"type": "text", "text": ...} -> {"type": "text", "text": ...}
# {"type": "image", "image": {"url": {"uri": ...}}} -> {"type": "image_url", "image_url": {"url": ...}}
# {"type": "image", "image": {"data": ...}} -> {"type": "image_url", "image_url": {"url": "data:image/?;base64,..."}}
# List[...] -> List[...]
async def _convert_message_content(
content: InterleavedContent,
) -> Union[str, Iterable[OpenAIChatCompletionContentPartParam]]:
async def impl(
content_: InterleavedContent,
) -> Union[
str,
OpenAIChatCompletionContentPartParam,
List[OpenAIChatCompletionContentPartParam],
]:
# Llama Stack and OpenAI spec match for str and text input
if isinstance(content_, str):
return content_
elif isinstance(content_, TextContentItem):
return OpenAIChatCompletionContentPartTextParam(
type="text",
text=content_.text,
)
elif isinstance(content_, ImageContentItem):
return OpenAIChatCompletionContentPartImageParam(
type="image_url",
image_url=OpenAIImageURL(url=await convert_image_content_to_url(content_)),
)
elif isinstance(content_, list):
return [await impl(item) for item in content_]
else:
raise ValueError(f"Unsupported content type: {type(content_)}")
ret = await impl(content)
# OpenAI*Message expects a str or list
if isinstance(ret, str) or isinstance(ret, list):
return ret
else:
return [ret]
out: OpenAIChatCompletionMessage = None
if isinstance(message, UserMessage):
out = OpenAIChatCompletionUserMessage(
role="user",
content=await _convert_message_content(message.content),
)
elif isinstance(message, CompletionMessage):
tool_calls = [
OpenAIChatCompletionMessageToolCall(
id=tool.call_id,
function=OpenAIFunction(
name=(tool.tool_name if not isinstance(tool.tool_name, BuiltinTool) else tool.tool_name.value),
arguments=json.dumps(tool.arguments),
),
type="function",
)
for tool in message.tool_calls
]
params = {}
if tool_calls:
params = {"tool_calls": tool_calls}
out = OpenAIChatCompletionAssistantMessage(
role="assistant",
content=await _convert_message_content(message.content),
**params,
)
elif isinstance(message, ToolResponseMessage):
out = OpenAIChatCompletionToolMessage(
role="tool",
tool_call_id=message.call_id,
content=await _convert_message_content(message.content),
)
elif isinstance(message, SystemMessage):
out = OpenAIChatCompletionSystemMessage(
role="system",
content=await _convert_message_content(message.content),
)
else:
raise ValueError(f"Unsupported message type: {type(message)}")
return out
def convert_tool_call(
tool_call: ChatCompletionMessageToolCall,
) -> Union[ToolCall, UnparseableToolCall]:
"""
Convert a ChatCompletionMessageToolCall tool call to either a
ToolCall or UnparseableToolCall. Returns an UnparseableToolCall
if the tool call is not valid ToolCall.
"""
try:
valid_tool_call = ToolCall(
call_id=tool_call.id,
tool_name=tool_call.function.name,
arguments=json.loads(tool_call.function.arguments),
arguments_json=tool_call.function.arguments,
)
except Exception:
return UnparseableToolCall(
call_id=tool_call.id or "",
tool_name=tool_call.function.name or "",
arguments=tool_call.function.arguments or "",
)
return valid_tool_call
PYTHON_TYPE_TO_LITELLM_TYPE = {
"int": "integer",
"float": "number",
"bool": "boolean",
"str": "string",
}
def to_openai_param_type(param_type: str) -> dict:
"""
Convert Python type hints to OpenAI parameter type format.
Examples:
'str' -> {'type': 'string'}
'int' -> {'type': 'integer'}
'list[str]' -> {'type': 'array', 'items': {'type': 'string'}}
'list[int]' -> {'type': 'array', 'items': {'type': 'integer'}}
"""
# Handle basic types first
basic_types = {
"str": "string",
"int": "integer",
"float": "number",
"bool": "boolean",
}
if param_type in basic_types:
return {"type": basic_types[param_type]}
# Handle list/array types
if param_type.startswith("list[") and param_type.endswith("]"):
inner_type = param_type[5:-1]
if inner_type in basic_types:
return {"type": "array", "items": {"type": basic_types.get(inner_type, inner_type)}}
return {"type": param_type}
def convert_tooldef_to_openai_tool(tool: ToolDefinition) -> dict:
"""
Convert a ToolDefinition to an OpenAI API-compatible dictionary.
ToolDefinition:
tool_name: str | BuiltinTool
description: Optional[str]
parameters: Optional[Dict[str, ToolParamDefinition]]
ToolParamDefinition:
param_type: str
description: Optional[str]
required: Optional[bool]
default: Optional[Any]
OpenAI spec -
{
"type": "function",
"function": {
"name": tool_name,
"description": description,
"parameters": {
"type": "object",
"properties": {
param_name: {
"type": param_type,
"description": description,
"default": default,
},
...
},
"required": [param_name, ...],
},
},
}
"""
out = {
"type": "function",
"function": {},
}
function = out["function"]
if isinstance(tool.tool_name, BuiltinTool):
function.update(name=tool.tool_name.value) # TODO(mf): is this sufficient?
else:
function.update(name=tool.tool_name)
if tool.description:
function.update(description=tool.description)
if tool.parameters:
parameters = {
"type": "object",
"properties": {},
}
properties = parameters["properties"]
required = []
for param_name, param in tool.parameters.items():
properties[param_name] = to_openai_param_type(param.param_type)
if param.description:
properties[param_name].update(description=param.description)
if param.default:
properties[param_name].update(default=param.default)
if param.required:
required.append(param_name)
if required:
parameters.update(required=required)
function.update(parameters=parameters)
return out
def _convert_openai_finish_reason(finish_reason: str) -> StopReason:
"""
Convert an OpenAI chat completion finish_reason to a StopReason.
finish_reason: Literal["stop", "length", "tool_calls", ...]
- stop: model hit a natural stop point or a provided stop sequence
- length: maximum number of tokens specified in the request was reached
- tool_calls: model called a tool
->
class StopReason(Enum):
end_of_turn = "end_of_turn"
end_of_message = "end_of_message"
out_of_tokens = "out_of_tokens"
"""
# TODO(mf): are end_of_turn and end_of_message semantics correct?
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 _convert_openai_tool_calls(
tool_calls: List[OpenAIChatCompletionMessageToolCall],
) -> List[ToolCall]:
"""
Convert an OpenAI ChatCompletionMessageToolCall list into a list of ToolCall.
OpenAI ChatCompletionMessageToolCall:
id: str
function: Function
type: Literal["function"]
OpenAI Function:
arguments: str
name: str
->
ToolCall:
call_id: str
tool_name: str
arguments: Dict[str, ...]
"""
if not tool_calls:
return [] # CompletionMessage tool_calls is not optional
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_openai_logprobs(
logprobs: OpenAIChoiceLogprobs,
) -> Optional[List[TokenLogProbs]]:
"""
Convert an OpenAI ChoiceLogprobs into a list of TokenLogProbs.
OpenAI ChoiceLogprobs:
content: Optional[List[ChatCompletionTokenLogprob]]
OpenAI ChatCompletionTokenLogprob:
token: str
logprob: float
top_logprobs: List[TopLogprob]
OpenAI TopLogprob:
token: str
logprob: float
->
TokenLogProbs:
logprobs_by_token: Dict[str, float]
- token, logprob
"""
if not logprobs or not logprobs.content:
return None
return [
TokenLogProbs(logprobs_by_token={logprobs.token: logprobs.logprob for logprobs in content.top_logprobs})
for content in logprobs.content
]
def _convert_openai_sampling_params(
max_tokens: Optional[int] = None,
temperature: Optional[float] = None,
top_p: Optional[float] = None,
) -> SamplingParams:
sampling_params = SamplingParams()
if max_tokens:
sampling_params.max_tokens = max_tokens
# Map an explicit temperature of 0 to greedy sampling
if temperature == 0:
strategy = GreedySamplingStrategy()
else:
# OpenAI defaults to 1.0 for temperature and top_p if unset
if temperature is None:
temperature = 1.0
if top_p is None:
top_p = 1.0
strategy = TopPSamplingStrategy(temperature=temperature, top_p=top_p)
sampling_params.strategy = strategy
return sampling_params
def convert_openai_chat_completion_choice(
choice: OpenAIChoice,
) -> ChatCompletionResponse:
"""
Convert an OpenAI Choice into a ChatCompletionResponse.
OpenAI Choice:
message: ChatCompletionMessage
finish_reason: str
logprobs: Optional[ChoiceLogprobs]
OpenAI ChatCompletionMessage:
role: Literal["assistant"]
content: Optional[str]
tool_calls: Optional[List[ChatCompletionMessageToolCall]]
->
ChatCompletionResponse:
completion_message: CompletionMessage
logprobs: Optional[List[TokenLogProbs]]
CompletionMessage:
role: Literal["assistant"]
content: str | ImageMedia | List[str | ImageMedia]
stop_reason: StopReason
tool_calls: List[ToolCall]
class StopReason(Enum):
end_of_turn = "end_of_turn"
end_of_message = "end_of_message"
out_of_tokens = "out_of_tokens"
"""
assert hasattr(choice, "message") and choice.message, "error in server response: message not found"
assert hasattr(choice, "finish_reason") and choice.finish_reason, (
"error in server response: finish_reason not found"
)
return ChatCompletionResponse(
completion_message=CompletionMessage(
content=choice.message.content or "", # CompletionMessage content is not optional
stop_reason=_convert_openai_finish_reason(choice.finish_reason),
tool_calls=_convert_openai_tool_calls(choice.message.tool_calls),
),
logprobs=_convert_openai_logprobs(getattr(choice, "logprobs", None)),
)
async def convert_openai_chat_completion_stream(
stream: AsyncStream[OpenAIChatCompletionChunk],
enable_incremental_tool_calls: bool,
) -> AsyncGenerator[ChatCompletionResponseStreamChunk, None]:
"""
Convert a stream of OpenAI chat completion chunks into a stream
of ChatCompletionResponseStreamChunk.
"""
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.start,
delta=TextDelta(text=""),
)
)
event_type = ChatCompletionResponseEventType.progress
stop_reason = None
tool_call_idx_to_buffer = {}
async for chunk in stream:
choice = chunk.choices[0] # assuming only one choice per chunk
# we assume there's only one finish_reason in the stream
stop_reason = _convert_openai_finish_reason(choice.finish_reason) or stop_reason
logprobs = getattr(choice, "logprobs", None)
# if there's a tool call, emit an event for each tool in the list
# if tool call and content, emit both separately
if choice.delta.tool_calls:
# the call may have content and a tool call. ChatCompletionResponseEvent
# does not support both, so we emit the content first
if choice.delta.content:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=event_type,
delta=TextDelta(text=choice.delta.content),
logprobs=_convert_openai_logprobs(logprobs),
)
)
# it is possible to have parallel tool calls in stream, but
# ChatCompletionResponseEvent only supports one per stream
if len(choice.delta.tool_calls) > 1:
warnings.warn(
"multiple tool calls found in a single delta, using the first, ignoring the rest",
stacklevel=2,
)
if not enable_incremental_tool_calls:
for tool_call in choice.delta.tool_calls:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=event_type,
delta=ToolCallDelta(
tool_call=_convert_openai_tool_calls([tool_call])[0],
parse_status=ToolCallParseStatus.succeeded,
),
logprobs=_convert_openai_logprobs(logprobs),
)
)
else:
for tool_call in choice.delta.tool_calls:
idx = tool_call.index if hasattr(tool_call, "index") else 0
if idx not in tool_call_idx_to_buffer:
tool_call_idx_to_buffer[idx] = {
"call_id": tool_call.id,
"name": None,
"arguments": "",
"content": "",
}
buffer = tool_call_idx_to_buffer[idx]
if tool_call.function:
if tool_call.function.name:
buffer["name"] = tool_call.function.name
delta = f"{buffer['name']}("
buffer["content"] += delta
if tool_call.function.arguments:
delta = tool_call.function.arguments
buffer["arguments"] += delta
buffer["content"] += delta
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=event_type,
delta=ToolCallDelta(
tool_call=delta,
parse_status=ToolCallParseStatus.in_progress,
),
logprobs=_convert_openai_logprobs(logprobs),
)
)
elif choice.delta.content:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=event_type,
delta=TextDelta(text=choice.delta.content or ""),
logprobs=_convert_openai_logprobs(logprobs),
)
)
for idx, buffer in tool_call_idx_to_buffer.items():
logger.debug(f"toolcall_buffer[{idx}]: {buffer}")
if buffer["name"]:
delta = ")"
buffer["content"] += delta
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=event_type,
delta=ToolCallDelta(
tool_call=delta,
parse_status=ToolCallParseStatus.in_progress,
),
logprobs=None,
)
)
try:
arguments = json.loads(buffer["arguments"])
tool_call = ToolCall(
call_id=buffer["call_id"],
tool_name=buffer["name"],
arguments=arguments,
arguments_json=buffer["arguments"],
)
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call=tool_call,
parse_status=ToolCallParseStatus.succeeded,
),
stop_reason=stop_reason,
)
)
except json.JSONDecodeError as e:
print(f"Failed to parse arguments: {e}")
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call=buffer["content"],
parse_status=ToolCallParseStatus.failed,
),
stop_reason=stop_reason,
)
)
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.complete,
delta=TextDelta(text=""),
stop_reason=stop_reason,
)
)
async def prepare_openai_completion_params(**params):
completion_params = {k: v for k, v in params.items() if v is not None}
return completion_params
class OpenAICompletionUnsupportedMixin:
async def openai_completion(
self,
model: str,
prompt: Union[str, List[str], List[int], List[List[int]]],
best_of: Optional[int] = None,
echo: Optional[bool] = None,
frequency_penalty: Optional[float] = None,
logit_bias: Optional[Dict[str, float]] = None,
logprobs: Optional[bool] = None,
max_tokens: Optional[int] = None,
n: Optional[int] = None,
presence_penalty: Optional[float] = None,
seed: Optional[int] = None,
stop: Optional[Union[str, List[str]]] = None,
stream: Optional[bool] = None,
stream_options: Optional[Dict[str, Any]] = None,
temperature: Optional[float] = None,
top_p: Optional[float] = None,
user: Optional[str] = None,
guided_choice: Optional[List[str]] = None,
prompt_logprobs: Optional[int] = None,
) -> OpenAICompletion:
if stream:
raise ValueError(f"{self.__class__.__name__} doesn't support streaming openai completions")
# This is a pretty hacky way to do emulate completions -
# basically just de-batches them...
prompts = [prompt] if not isinstance(prompt, list) else prompt
sampling_params = _convert_openai_sampling_params(
max_tokens=max_tokens,
temperature=temperature,
top_p=top_p,
)
choices = []
# "n" is the number of completions to generate per prompt
for _i in range(0, n):
# and we may have multiple prompts, if batching was used
for prompt in prompts:
result = self.completion(
model_id=model,
content=prompt,
sampling_params=sampling_params,
)
index = len(choices)
text = result.content
finish_reason = _convert_openai_finish_reason(result.stop_reason)
choice = OpenAICompletionChoice(
index=index,
text=text,
finish_reason=finish_reason,
)
choices.append(choice)
return OpenAICompletion(
id=f"cmpl-{uuid.uuid4()}",
choices=choices,
created=int(time.time()),
model=model,
object="text_completion",
)
class OpenAIChatCompletionUnsupportedMixin:
async def openai_chat_completion(
self,
model: str,
messages: List[OpenAIChatCompletionMessage],
frequency_penalty: Optional[float] = None,
function_call: Optional[Union[str, Dict[str, Any]]] = None,
functions: Optional[List[Dict[str, Any]]] = None,
logit_bias: Optional[Dict[str, float]] = None,
logprobs: Optional[bool] = None,
max_completion_tokens: Optional[int] = None,
max_tokens: Optional[int] = None,
n: Optional[int] = None,
parallel_tool_calls: Optional[bool] = None,
presence_penalty: Optional[float] = None,
response_format: Optional[Dict[str, str]] = None,
seed: Optional[int] = None,
stop: Optional[Union[str, List[str]]] = None,
stream: Optional[bool] = None,
stream_options: Optional[Dict[str, Any]] = None,
temperature: Optional[float] = None,
tool_choice: Optional[Union[str, Dict[str, Any]]] = None,
tools: Optional[List[Dict[str, Any]]] = None,
top_logprobs: Optional[int] = None,
top_p: Optional[float] = None,
user: Optional[str] = None,
) -> OpenAIChatCompletion:
raise ValueError(f"{self.__class__.__name__} doesn't support openai chat completion")