2025-03-02 17:34:51 -08:00

127 lines
5.6 KiB
Python

# SPDX-License-Identifier: Apache-2.0
from collections.abc import Iterable
from typing import Union
from vllm.entrypoints.openai.protocol import (ChatCompletionRequest,
DeltaMessage,
ExtractedToolCallInformation,
FunctionCall, ToolCall)
from vllm.entrypoints.openai.tool_parsers import ToolParser
class StreamingToolReconstructor:
def __init__(self, assert_one_tool_per_delta: bool = True):
self.tool_calls: list[ToolCall] = []
self.other_content: str = ""
self._assert_one_tool_per_delta = assert_one_tool_per_delta
def append_delta(self, delta: DeltaMessage):
if delta.content is not None:
self.other_content += delta.content
else:
assert delta.tool_calls, (
"Streaming results should have either content or tool calls "
"(or both)")
if self._assert_one_tool_per_delta:
# Note: This isn't strictly required by the API and may not be
# possible to adhere to depending on the token space and number of
# tokens per streamed response from the model, but it is required
# by tool_use tests, so we enforce it here by default also.
assert len(delta.tool_calls) < 2, (
"Streaming should include only one tool call per update.")
for call_delta in delta.tool_calls:
assert call_delta.type == "function", (
"Streaming tool calls should only emit function calls. Got "
f"{call_delta.type}")
current_tool_call = self.tool_calls[
call_delta.index] if call_delta.index < len(
self.tool_calls) else None
if current_tool_call:
assert (not call_delta.function.name), (
"Streaming tool calls should emit the full function name "
f"exactly once. Got {call_delta.function.name}")
assert (not call_delta.id), (
"Streaming tool calls must emit function id only once. Got "
f"{call_delta.id}")
assert (call_delta.index == len(self.tool_calls) - 1), (
f"Incorrect index for tool delta. Got {call_delta.index}, "
f"expected {len(self.tool_calls) - 1}")
current_tool_call.function.arguments += (
call_delta.function.arguments)
else:
assert call_delta.id is not None, (
"Streaming tool calls must have an id on first appearance")
assert call_delta.function.name is not None, (
"Streaming tool calls must have a function name on first "
"appearance")
assert call_delta.index == len(self.tool_calls), (
f"Incorrect index for tool delta. Got {call_delta.index}, "
f"expected {len(self.tool_calls)}")
self.tool_calls.append(
ToolCall(id=call_delta.id,
function=FunctionCall(
name=call_delta.function.name,
arguments=call_delta.function.arguments
or "")))
def run_tool_extraction(
tool_parser: ToolParser,
model_output: str,
request: Union[ChatCompletionRequest, None] = None,
streaming: bool = False,
assert_one_tool_per_delta: bool = True,
) -> tuple[Union[str, None], list[ToolCall]]:
if streaming:
reconstructor = run_tool_extraction_streaming(
tool_parser,
model_output,
request,
assert_one_tool_per_delta=assert_one_tool_per_delta)
return reconstructor.other_content or None, reconstructor.tool_calls
else:
extracted = run_tool_extraction_nonstreaming(tool_parser, model_output,
request)
assert extracted.tools_called == bool(extracted.tool_calls)
return extracted.content, extracted.tool_calls
def run_tool_extraction_nonstreaming(
tool_parser: ToolParser,
model_output: str,
request: Union[ChatCompletionRequest, None] = None
) -> ExtractedToolCallInformation:
request = request or ChatCompletionRequest(messages=[], model="test-model")
return tool_parser.extract_tool_calls(model_output, request)
def run_tool_extraction_streaming(
tool_parser: ToolParser,
model_deltas: Iterable[str],
request: Union[ChatCompletionRequest, None] = None,
assert_one_tool_per_delta: bool = True,
) -> StreamingToolReconstructor:
request = request or ChatCompletionRequest(messages=[], model="test-model")
reconstructor = StreamingToolReconstructor(
assert_one_tool_per_delta=assert_one_tool_per_delta)
previous_text = ""
previous_tokens: list[int] = []
for delta in model_deltas:
token_delta = [
tool_parser.vocab.get(token)
for token in tool_parser.model_tokenizer.tokenize(delta)
if token in tool_parser.vocab
]
current_text = previous_text + delta
current_tokens = previous_tokens + token_delta
delta_message = tool_parser.extract_tool_calls_streaming(
previous_text, current_text, delta, previous_tokens,
current_tokens, token_delta, request)
if delta_message is not None:
reconstructor.append_delta(delta_message)
previous_text = current_text
previous_tokens = current_tokens
return reconstructor