refactor: split infer core into subpackages by concern

- Eliminate core/ directory into cache/, runtime/, network/ subpackages plus flat modules
- Split cache.py (647 lines) into cache/{buffer,strategy,pool}.py by layer
- Add explicit ContiguousStrategy, make AllocationStrategy a real ABC
- Move TaskCacheState to cache/strategy.py, drop string forward references
- Rename api/ to network/, server.py to app.py
- Move sample.py into runtime/ alongside executor and graph
- Simplify TaskCacheManager.__init__ to single pool param
- Expose pool.strategy and pool.req_pool as public properties
- Fix KVCache import in attention_backend.py (TYPE_CHECKING guard)
- Fix steady-state decode reading uninitialized position_ids on first step
This commit is contained in:
2026-08-08 23:43:05 +08:00
parent 3fa7e66676
commit 0c1b7664c1
37 changed files with 920 additions and 800 deletions
+39
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"""Inference API: protocol handler, stop checker, tool parsers, and FastAPI server.
``app`` is no longer a module-level global. Use :func:`get_app` to access the
lazy singleton FastAPI instance.
"""
from astrai.inference.network.app import (
AnthropicMessage,
ChatCompletionRequest,
ChatMessage,
FunctionDef,
MessagesRequest,
ToolDef,
get_app,
run_server,
)
from astrai.inference.network.protocol import GenContext, ProtocolHandler, StopChecker
from astrai.inference.network.tool_parser import (
BaseToolParser,
SimpleJsonToolParser,
ToolParserFactory,
)
__all__ = [
"ProtocolHandler",
"StopChecker",
"GenContext",
"BaseToolParser",
"SimpleJsonToolParser",
"ToolParserFactory",
"AnthropicMessage",
"ChatCompletionRequest",
"ChatMessage",
"FunctionDef",
"ToolDef",
"MessagesRequest",
"get_app",
"run_server",
]
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"""Anthropic message completion response builder."""
import time
import uuid
from typing import Any, Dict, List, Tuple, Union
from pydantic import BaseModel
from astrai.inference.engine import InferenceEngine
from astrai.inference.network.protocol import (
GenContext,
ResponseBuilder,
StopInfo,
sse_event,
)
def _extract_text(content: Union[str, List[Dict[str, Any]]]) -> str:
if isinstance(content, str):
return content
if isinstance(content, list):
for block in content:
if isinstance(block, dict) and block.get("type") == "text":
return block.get("text", "")
return ""
class AnthropicResponseBuilder(ResponseBuilder):
def prepare(
self, request: BaseModel, engine: InferenceEngine
) -> Tuple[str, GenContext, List[str]]:
messages: List[Dict[str, str]] = []
system = getattr(request, "system", None)
if system:
messages.append({"role": "system", "content": system})
for m in request.messages:
text = _extract_text(m.content)
if text:
messages.append({"role": m.role, "content": text})
prompt = engine.tokenizer.apply_chat_template(messages, tokenize=False)
ctx = GenContext(
resp_id=f"msg_{uuid.uuid4().hex[:24]}",
created=int(time.time()),
model=request.model,
)
stop_sequences = getattr(request, "stop_sequences", None) or []
return prompt, ctx, stop_sequences
def format_stream_start(self, ctx: GenContext) -> List[str]:
return [
sse_event(
{
"type": "message_start",
"message": {
"id": ctx.resp_id,
"type": "message",
"role": "assistant",
"model": ctx.model,
"content": [],
"usage": {"input_tokens": ctx.prompt_tokens},
},
},
event="message_start",
),
sse_event(
{
"type": "content_block_start",
"index": 0,
"content_block": {"type": "text", "text": ""},
},
event="content_block_start",
),
]
def format_chunk(self, token: str, **kwargs) -> List[str]:
return [
sse_event(
{
"type": "content_block_delta",
"index": 0,
"delta": {"type": "text_delta", "text": token},
},
event="content_block_delta",
)
]
def format_stream_end(self, ctx: GenContext, stop: StopInfo) -> List[str]:
events: List[str] = []
if stop.matched:
trimmed = stop.body[: stop.body.rfind(stop.matched)]
unyielded = trimmed[len(stop.yielded) :]
if unyielded:
events.append(
sse_event(
{
"type": "content_block_delta",
"index": 0,
"delta": {"type": "text_delta", "text": unyielded},
},
event="content_block_delta",
)
)
events.append(
sse_event(
{"type": "content_block_stop", "index": 0},
event="content_block_stop",
)
)
events.append(
sse_event(
{
"type": "message_delta",
"delta": {
"stop_reason": "stop_sequence" if stop.matched else "end_turn",
"stop_sequence": stop.matched,
},
"usage": {"output_tokens": ctx.completion_tokens},
},
event="message_delta",
)
)
events.append(sse_event({"type": "message_stop"}, event="message_stop"))
return events
def format_response(
self, ctx: GenContext, content: str, stop: StopInfo
) -> Dict[str, Any]:
if stop.matched:
content = content[: content.rfind(stop.matched)]
return {
"id": ctx.resp_id,
"type": "message",
"role": "assistant",
"model": ctx.model,
"content": [{"type": "text", "text": content}],
"stop_reason": "stop_sequence" if stop.matched else "end_turn",
"stop_sequence": stop.matched,
"usage": {
"input_tokens": ctx.prompt_tokens,
"output_tokens": ctx.completion_tokens,
},
}
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"""
OpenAI / Anthropic-compatible chat completion server backed by continuous-batching inference.
Protocol-specific formatting is delegated to ``astrai.inference.protocol``.
This module owns the FastAPI app, request/response schemas, and dependency wiring.
``app`` is lazily constructed — importing this module does NOT create a FastAPI instance.
Use :func:`get_app` to access the singleton.
"""
import logging
from contextlib import asynccontextmanager
from pathlib import Path
from typing import Any, Dict, List, Optional, Union
import torch
import uvicorn
from fastapi import APIRouter, FastAPI, HTTPException
from pydantic import BaseModel, Field
from astrai.inference.engine import InferenceEngine
from astrai.inference.network.anthropic import AnthropicResponseBuilder
from astrai.inference.network.openai import OpenAIResponseBuilder
from astrai.inference.network.protocol import ProtocolHandler
from astrai.model import AutoModel
from astrai.tokenize import AutoTokenizer
logger = logging.getLogger(__name__)
_app_instance: Optional[FastAPI] = None
class ChatMessage(BaseModel):
role: str
content: Optional[str] = None
tool_calls: Optional[List[Dict[str, Any]]] = None
tool_call_id: Optional[str] = None
class FunctionDef(BaseModel):
name: str
description: Optional[str] = None
parameters: Optional[Dict[str, Any]] = None
class ToolDef(BaseModel):
type: str = "function"
function: FunctionDef
class ChatCompletionRequest(BaseModel):
"""OpenAI Chat Completion API request body."""
model: str = "astrai"
messages: List[ChatMessage]
temperature: Optional[float] = Field(default=1.0, ge=0.0, le=2.0)
top_p: Optional[float] = Field(default=1.0, ge=0.0, le=1.0)
top_k: Optional[int] = Field(default=50, ge=1)
stream: Optional[bool] = False
stop: Optional[Union[str, List[str]]] = None
max_tokens: Optional[int] = Field(default=2048, ge=1)
n: Optional[int] = Field(default=1, ge=1)
presence_penalty: Optional[float] = Field(default=0.0, ge=-2.0, le=2.0)
frequency_penalty: Optional[float] = Field(default=0.0, ge=-2.0, le=2.0)
logit_bias: Optional[Dict[int, float]] = None
user: Optional[str] = None
tools: Optional[List[ToolDef]] = None
tool_choice: Optional[Union[str, Dict[str, Any]]] = "auto"
class AnthropicMessage(BaseModel):
role: str
content: Union[str, List[Dict[str, Any]]]
class MessagesRequest(BaseModel):
"""Anthropic Messages API request body."""
model: str = "astrai"
max_tokens: int = Field(default=1024, ge=1)
messages: List[AnthropicMessage]
system: Optional[str] = None
temperature: Optional[float] = Field(default=1.0, ge=0.0, le=2.0)
top_p: Optional[float] = Field(default=1.0, ge=0.0, le=1.0)
top_k: Optional[int] = Field(default=50, ge=1)
stream: Optional[bool] = False
stop_sequences: Optional[List[str]] = None
@asynccontextmanager
async def lifespan(app: FastAPI):
config = app.state.server_config
if not config.get("_test", False):
try:
app.state.engine = _create_engine(**config)
except Exception as e:
logger.error(f"Failed to load model: {e}")
raise
yield
if app.state.engine:
app.state.engine.shutdown()
logger.info("Inference engine shutdown complete")
router = APIRouter()
def _create_engine(
param_path: Path,
device: str = "cuda",
dtype: torch.dtype = torch.bfloat16,
max_batch_size: int = 16,
max_seq_len: Optional[int] = None,
) -> InferenceEngine:
if not param_path.exists():
raise FileNotFoundError(f"Parameter directory not found: {param_path}")
tokenizer = AutoTokenizer.from_pretrained(param_path)
model = AutoModel.from_pretrained(param_path)
model.to(device=device, dtype=dtype)
logger.info(f"Model loaded on {device} with dtype {dtype}")
engine = InferenceEngine(
model=model,
tokenizer=tokenizer,
max_batch_size=max_batch_size,
max_seq_len=max_seq_len,
)
logger.info(f"Inference engine initialized with max_batch_size={max_batch_size}")
return engine
def get_app() -> FastAPI:
"""Return the singleton FastAPI instance (lazily created on first call)."""
global _app_instance
if _app_instance is None:
_app_instance = FastAPI(
title="AstrAI Inference Server",
version="0.2.0",
lifespan=lifespan,
)
_app_instance.include_router(router)
_app_instance.state.server_config = {}
_app_instance.state.engine = None
return _app_instance
def _get_engine() -> InferenceEngine:
engine = get_app().state.engine
if engine is None:
raise HTTPException(status_code=503, detail="Engine not initialized")
return engine
@router.get("/health")
async def health():
app = get_app()
return {
"status": "ok",
"model_loaded": app.state.engine is not None,
}
@router.get("/stats")
async def get_stats():
return _get_engine().get_stats()
@router.post("/v1/chat/completions")
async def chat_completion(request: ChatCompletionRequest):
engine = _get_engine()
handler = ProtocolHandler(request, engine, OpenAIResponseBuilder())
return await handler.handle()
@router.post("/v1/messages")
async def create_message(request: MessagesRequest):
engine = _get_engine()
handler = ProtocolHandler(request, engine, AnthropicResponseBuilder())
return await handler.handle()
def run_server(
param_path: Path,
host: str = "0.0.0.0",
port: int = 8000,
reload: bool = False,
device: str = "cuda",
dtype: torch.dtype = torch.bfloat16,
max_batch_size: int = 16,
max_seq_len: Optional[int] = None,
):
app = get_app()
app.state.server_config = {
"device": device,
"dtype": dtype,
"param_path": param_path,
"max_batch_size": max_batch_size,
"max_seq_len": max_seq_len,
}
uvicorn.run(
app,
host=host,
port=port,
reload=reload,
)
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"""OpenAI chat completion response builder."""
import logging
import time
import uuid
from typing import Any, Dict, List, Optional, Tuple, Union
from pydantic import BaseModel
from astrai.inference.engine import InferenceEngine
from astrai.inference.network.protocol import (
GenContext,
ResponseBuilder,
StopInfo,
sse_event,
)
from astrai.inference.network.tool_parser import BaseToolParser, ToolParserFactory
logger = logging.getLogger(__name__)
_UNSUPPORTED_PARAMS = (
"n",
"presence_penalty",
"logit_bias",
"user",
)
def _resolve_tool_choice(
request: BaseModel,
) -> Union[str, Dict[str, Any]]:
tc = getattr(request, "tool_choice", None)
if tc is None:
return "auto"
if isinstance(tc, str):
return tc
if isinstance(tc, dict):
return tc
return "auto"
def _resolve_tools(request: BaseModel) -> Optional[List[Dict[str, Any]]]:
raw = getattr(request, "tools", None)
if not raw:
return None
if isinstance(raw, list):
return [t.model_dump() if hasattr(t, "model_dump") else t for t in raw]
return None
class OpenAIResponseBuilder(ResponseBuilder):
def prepare(
self, request: BaseModel, engine: InferenceEngine
) -> Tuple[str, GenContext, List[str]]:
messages = [{"role": m.role, "content": m.content} for m in request.messages]
tools = _resolve_tools(request)
prompt = engine.tokenizer.apply_chat_template(
messages, tokenize=False, tools=tools or []
)
self._resp_id = f"chatcmpl-{uuid.uuid4().hex[:12]}"
self._model = request.model
for param in _UNSUPPORTED_PARAMS:
value = getattr(request, param, None)
fields = getattr(type(request), "model_fields", {})
default = fields[param].default if param in fields else None
if value is not None and value != default:
logger.warning(
"ChatCompletionRequest param '%s'=%r is not supported"
" and will be ignored",
param,
value,
)
self._parser: Optional[BaseToolParser] = None
if tools:
tool_choice = _resolve_tool_choice(request)
self._parser = ToolParserFactory.create(
"simple_json", tools=tools, tool_choice=tool_choice
)
self._content_started = False
ctx = GenContext(
resp_id=self._resp_id,
created=int(time.time()),
model=self._model,
)
stop = request.stop
stop_sequences = (
[] if stop is None else [stop] if isinstance(stop, str) else stop
)
return prompt, ctx, stop_sequences
def format_stream_start(self, ctx: GenContext) -> List[str]:
return [
sse_event(
{
"id": self._resp_id,
"object": "chat.completion.chunk",
"created": ctx.created,
"model": self._model,
"choices": [
{
"index": 0,
"delta": {"role": "assistant"},
"finish_reason": None,
}
],
}
)
]
def format_chunk(self, token: str, **kwargs) -> List[str]:
body = kwargs.get("body", "")
if self._parser is not None:
return self._format_tool_chunk(body, **kwargs)
return [
sse_event(
{
"id": self._resp_id,
"object": "chat.completion.chunk",
"created": 0,
"model": self._model,
"choices": [
{
"index": 0,
"delta": {"content": token},
"finish_reason": None,
}
],
}
)
]
def _format_tool_chunk(self, body: str, **kwargs) -> List[str]:
deltas = self._parser.feed(
body,
current_token_ids=kwargs.get("current_token_ids"),
delta_token_ids=kwargs.get("delta_token_ids"),
)
events: List[str] = []
for d in deltas:
if "content" in d:
if not self._content_started:
events.append(self._role_chunk())
self._content_started = True
events.append(
sse_event(
{
"id": self._resp_id,
"object": "chat.completion.chunk",
"created": 0,
"model": self._model,
"choices": [
{
"index": 0,
"delta": {"content": d["content"]},
"finish_reason": None,
}
],
}
)
)
elif "tool_calls" in d:
if not self._content_started:
events.append(self._role_chunk())
self._content_started = True
events.append(
sse_event(
{
"id": self._resp_id,
"object": "chat.completion.chunk",
"created": 0,
"model": self._model,
"choices": [
{
"index": 0,
"delta": {"tool_calls": d["tool_calls"]},
"finish_reason": None,
}
],
}
)
)
return events
def _role_chunk(self) -> str:
return sse_event(
{
"id": self._resp_id,
"object": "chat.completion.chunk",
"created": 0,
"model": self._model,
"choices": [
{
"index": 0,
"delta": {"role": "assistant"},
"finish_reason": None,
}
],
}
)
def format_stream_end(self, ctx: GenContext, stop: StopInfo) -> List[str]:
finish_reason = "stop"
if self._parser is not None and self._parser.has_tool_calls:
finish_reason = "tool_calls"
return [
sse_event(
{
"id": self._resp_id,
"object": "chat.completion.chunk",
"created": ctx.created,
"model": self._model,
"choices": [
{"index": 0, "delta": {}, "finish_reason": finish_reason}
],
}
),
sse_event(
{
"prompt_tokens": ctx.prompt_tokens,
"completion_tokens": ctx.completion_tokens,
"total_tokens": ctx.prompt_tokens + ctx.completion_tokens,
}
),
]
def format_response(
self, ctx: GenContext, content: str, stop: StopInfo
) -> Dict[str, Any]:
if self._parser is not None:
parsed = self._parser.parse_complete(content)
if parsed and parsed.get("tool_calls"):
return {
"id": self._resp_id,
"object": "chat.completion",
"created": ctx.created,
"model": self._model,
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": parsed.get("content"),
"tool_calls": parsed["tool_calls"],
},
"finish_reason": "tool_calls",
}
],
"usage": {
"prompt_tokens": ctx.prompt_tokens,
"completion_tokens": ctx.completion_tokens,
"total_tokens": ctx.prompt_tokens + ctx.completion_tokens,
},
}
return {
"id": self._resp_id,
"object": "chat.completion",
"created": ctx.created,
"model": self._model,
"choices": [
{
"index": 0,
"message": {"role": "assistant", "content": content},
"finish_reason": "stop",
}
],
"usage": {
"prompt_tokens": ctx.prompt_tokens,
"completion_tokens": ctx.completion_tokens,
"total_tokens": ctx.prompt_tokens + ctx.completion_tokens,
},
}
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"""Orchestration layer: ProtocolHandler, StopChecker, GenContext, StopInfo, ResponseBuilder, SSE utils.
ProtocolHandler orchestrates the async generation loop and delegates
protocol-specific formatting to a ResponseBuilder.
"""
import json
from abc import ABC, abstractmethod
from dataclasses import dataclass
from typing import Any, AsyncGenerator, Dict, List, Optional, Tuple, Union
from fastapi.responses import StreamingResponse
from pydantic import BaseModel
from astrai.inference.engine import InferenceEngine
def sse_event(data: Dict[str, Any], event: Optional[str] = None) -> str:
lines: List[str] = []
if event:
lines.append(f"event: {event}")
lines.append(f"data: {json.dumps(data, ensure_ascii=False)}")
lines.append("")
return "\n".join(lines)
def sse_done() -> str:
return "data: [DONE]\n\n"
@dataclass
class GenContext:
"""Per-generation metadata passed to builder format methods."""
resp_id: str
created: int
model: str
prompt_tokens: int = 0
completion_tokens: int = 0
@dataclass
class StopInfo:
"""Stop-check result passed to format_stream_end / format_response."""
matched: Optional[str] = None
body: str = ""
yielded: str = ""
class StopChecker:
"""Scans accumulated text for stop sequence matches."""
def __init__(self, sequences: List[str]):
self._sequences = [s for s in sequences if s]
def check(self, text: str) -> Optional[str]:
for seq in self._sequences:
if seq in text:
return seq
return None
class ResponseBuilder(ABC):
"""Interface for protocol-specific response formatting.
A new protocol requires one concrete builder implementing 5 methods.
"""
@abstractmethod
def prepare(
self, request: BaseModel, engine: InferenceEngine
) -> Tuple[str, GenContext, List[str]]:
"""Return (prompt, ctx, stop_sequences) for a generation request."""
@abstractmethod
def format_stream_start(self, ctx: GenContext) -> List[str]:
"""SSE events that open the stream."""
@abstractmethod
def format_chunk(self, token: str, **kwargs) -> List[str]:
"""SSE events for a single generated token.
``body`` (the full accumulated text so far) is always provided
as a keyword argument. Additional keyword arguments such as
``current_token_ids`` and ``delta_token_ids`` may be included
for tool parsers that need token-level information.
Returns a list of SSE event strings (may be empty).
"""
@abstractmethod
def format_stream_end(self, ctx: GenContext, stop: StopInfo) -> List[str]:
"""SSE events that close the stream."""
@abstractmethod
def format_response(
self, ctx: GenContext, content: str, stop: StopInfo
) -> Dict[str, Any]:
"""JSON response body for non-streaming mode."""
class ProtocolHandler:
"""Orchestrates the generation loop, delegates formatting to a builder.
Usage::
handler = ProtocolHandler(request, engine, OpenAIResponseBuilder())
response = await handler.handle()
"""
def __init__(
self, request: BaseModel, engine: InferenceEngine, builder: ResponseBuilder
):
self.request = request
self.engine = engine
self.builder = builder
async def handle(self) -> Union[StreamingResponse, Dict[str, Any]]:
prompt, ctx, stop_sequences = self.builder.prepare(self.request, self.engine)
ctx.prompt_tokens = len(self.engine.tokenizer.encode(prompt))
agen = self.engine.generate_async(
prompt=prompt,
max_tokens=self.request.max_tokens,
temperature=self.request.temperature,
top_p=self.request.top_p,
top_k=self.request.top_k,
frequency_penalty=getattr(self.request, "frequency_penalty", 0.0),
)
if self.request.stream:
return self._handle_stream(agen, ctx, stop_sequences)
else:
return await self._handle_non_stream(agen, ctx, stop_sequences)
def _handle_stream(
self, agen: AsyncGenerator, ctx: GenContext, stop_sequences: List[str]
) -> StreamingResponse:
checker = StopChecker(stop_sequences)
async def event_stream():
for event in self.builder.format_stream_start(ctx):
yield event
body = ""
yielded = ""
matched = None
token_ids: List[int] = []
async for token in agen:
body += token
new_ids = self.engine.tokenizer.encode(token)
token_ids.extend(new_ids)
matched = checker.check(body)
if matched:
break
ctx.completion_tokens += 1
for event in self.builder.format_chunk(
token,
body=body,
current_token_ids=token_ids,
delta_token_ids=new_ids,
):
yield event
yielded += token
stop = StopInfo(matched=matched, body=body, yielded=yielded)
for event in self.builder.format_stream_end(ctx, stop):
yield event
yield sse_done()
return StreamingResponse(
event_stream(),
media_type="text/event-stream",
headers={"Cache-Control": "no-cache", "Connection": "keep-alive"},
)
async def _handle_non_stream(
self, agen: AsyncGenerator, ctx: GenContext, stop_sequences: List[str]
) -> Dict[str, Any]:
checker = StopChecker(stop_sequences)
body = ""
matched = None
async for token in agen:
body += token
matched = checker.check(body)
if matched:
break
ctx.completion_tokens += 1
stop = StopInfo(matched=matched, body=body)
return self.builder.format_response(ctx, body, stop)
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"""Tool call parsers for extracting structured tool calls from model output.
Patterned after vLLM's ToolParser abstraction. Each parser knows how to
detect and incrementally extract tool calls from raw generated text.
Subclasses may optionally consume ``token_ids`` for token-level parsing
(e.g. Harmony / VLM-style parsers).
"""
import json
import re
import uuid
from abc import ABC, abstractmethod
from typing import Dict, List, Optional
from astrai.factory import BaseFactory
class BaseToolParser(ABC):
"""Abstract tool call parser — one instance per request.
Maintains streaming state internally so that each call to :meth:`feed`
can diff against previously emitted content.
Args:
tools (list of dict, optional): Tool definitions from the request.
tool_choice (str): ``"auto"`` / ``"required"`` / ``"none"`` or a named
tool choice dict.
"""
def __init__(self, tools: Optional[List[Dict]] = None, tool_choice: str = "auto"):
self.tools = tools or []
self.tool_choice = tool_choice
@abstractmethod
def feed(
self,
body: str,
current_token_ids: Optional[List[int]] = None,
delta_token_ids: Optional[List[int]] = None,
) -> List[Dict]:
"""Feed the *full* accumulated text each step.
Returns a list of delta dicts to emit. Each delta is one of:
- ``{"content": "text"}`` — plain text delta
- ``{"tool_calls": [...]}`` — tool-call delta (OpenAI format)
Returns an empty list when nothing new should be emitted.
Args:
body (str): The complete accumulated generated text so far.
current_token_ids (list of int, optional): All token IDs decoded
into *body* (cumulative).
delta_token_ids (list of int, optional): Only the token IDs for
this chunk.
"""
@abstractmethod
def parse_complete(self, body: str) -> Optional[Dict]:
"""Parse the *complete* generated text after generation ends.
Returns ``None`` when no tool calls were found, otherwise a dict
with ``content`` (str or None) and ``tool_calls`` (list of dicts).
"""
@property
@abstractmethod
def has_tool_calls(self) -> bool:
"""True if the parser detected at least one tool call in the stream."""
class ToolParserFactory(BaseFactory["BaseToolParser"]):
pass
_TOOL_CALL_HEAD_RE = re.compile(r'\{\s*"name"\s*:')
def _scan_json(text: str, start: int = 0):
"""Scan for a complete JSON object starting at *start*.
Returns ``(end, complete)`` where *end* is one-past the closing
brace (or ``len(text)`` if unclosed), and *complete* is a bool.
"""
depth = 0
in_string = False
escape = False
for i in range(start, len(text)):
c = text[i]
if escape:
escape = False
continue
if c == "\\":
escape = True
continue
if c == '"':
in_string = not in_string
continue
if in_string:
continue
if c == "{":
depth += 1
elif c == "}":
depth -= 1
if depth == 0:
return i + 1, True
return len(text), False
def _parse_tool_call_json(json_str: str, complete: bool):
"""Extract *name* and *arguments* from a tool-call JSON string.
Returns ``(name, args, valid)``.
"""
if complete:
try:
obj = json.loads(json_str)
except json.JSONDecodeError:
return None, "", False
name = obj.get("name")
if not isinstance(name, str) or not name:
return None, "", False
args = obj.get("arguments")
if isinstance(args, dict):
if not args:
args = ""
else:
args = json.dumps(args, ensure_ascii=False)
args = args[1:-1].rstrip()
elif isinstance(args, list):
args = json.dumps(args, ensure_ascii=False) if args else ""
elif isinstance(args, str):
pass
else:
args = str(args) if args is not None else ""
return name, args, True
name_match = re.search(r'"name"\s*:\s*"([^"]*)"', json_str)
if not name_match:
return None, "", False
name = name_match.group(1)
args_match = re.search(r'"arguments"\s*:\s*(.*)', json_str, re.DOTALL)
if not args_match:
return name, "", True
raw = args_match.group(1).rstrip()
if raw.startswith("{"):
inner = raw[1:].rstrip()
if inner.endswith("}"):
inner = inner[:-1].rstrip()
raw = inner
return name, raw, True
def _find_tool_calls(text: str, start_pos: int = 0):
"""Find all complete ``{...}`` tool-call objects in *text*.
Returns a list of dicts with keys *start*, *end*, *name*, *args*,
*complete*.
"""
results = []
pos = start_pos
while True:
brace = text.find("{", pos)
if brace == -1:
break
end, complete = _scan_json(text, brace)
if not complete:
break
json_str = text[brace:end]
name, args, valid = _parse_tool_call_json(json_str, complete=True)
if not valid or name is None:
pos = end
continue
results.append(
{
"start": brace,
"end": end,
"name": name,
"args": args,
"complete": True,
}
)
pos = end
return results
def _find_partial_tool_call(text: str, start_pos: int = 0):
"""Find one incomplete (still-generating) tool-call JSON object."""
brace = text.find("{", start_pos)
if brace == -1:
return None
json_str = text[brace:]
if '"name"' not in json_str:
return None
name, args, valid = _parse_tool_call_json(json_str, complete=False)
if not valid or name is None:
return None
return {
"start": brace,
"name": name,
"args": args,
"complete": False,
}
@ToolParserFactory.register("simple_json")
class SimpleJsonToolParser(BaseToolParser):
"""Parser for models that output tool calls as plain JSON objects.
Detects ``{"name": "<func>", "arguments": {...}}`` anywhere in the
generated text. Handles single and (non-overlapping) multiple tool
calls. Text preceding the first tool call is emitted as plain
``content`` deltas.
"""
def __init__(self, tools=None, tool_choice="auto"):
super().__init__(tools, tool_choice)
self._emitted_content_len = 0
self._tc_state: List[Dict] = []
self._has_tool_calls = False
# -------------------------------------------------------------- feed
def feed(
self,
body: str,
current_token_ids: Optional[List[int]] = None,
delta_token_ids: Optional[List[int]] = None,
) -> List[Dict]:
deltas: List[Dict] = []
completed = _find_tool_calls(body)
if not completed:
partial = _find_partial_tool_call(body)
if not partial:
return self._emit_plain_content(body, deltas)
all_tcs = [partial]
else:
all_tcs = completed
partial = _find_partial_tool_call(body, completed[-1]["end"])
if partial:
all_tcs = completed + [partial]
first_start = all_tcs[0]["start"]
if first_start > self._emitted_content_len:
content = body[self._emitted_content_len : first_start]
self._emitted_content_len = first_start
if content:
deltas.append({"content": content})
for i, tc in enumerate(all_tcs):
if i >= len(self._tc_state):
self._tc_state.append(
{
"id": f"call_{uuid.uuid4().hex[:12]}",
"name_emitted": False,
"args_emitted_len": 0,
}
)
self._has_tool_calls = True
st = self._tc_state[i]
if not st["name_emitted"]:
st["name_emitted"] = True
deltas.append(
{
"tool_calls": [
{
"index": i,
"id": st["id"],
"type": "function",
"function": {"name": tc["name"], "arguments": ""},
}
]
}
)
new_args = tc["args"]
if len(new_args) > st["args_emitted_len"]:
diff = new_args[st["args_emitted_len"] :]
st["args_emitted_len"] = len(new_args)
deltas.append(
{
"tool_calls": [
{
"index": i,
"function": {"arguments": diff},
}
]
}
)
return deltas
def _emit_plain_content(self, body: str, deltas: List[Dict]) -> List[Dict]:
new_content = body[self._emitted_content_len :]
if new_content:
self._emitted_content_len = len(body)
deltas.append({"content": new_content})
return deltas
# -------------------------------------------------------- complete
def parse_complete(self, body: str) -> Optional[Dict]:
completed = _find_tool_calls(body)
if not completed:
return None
content = body[: completed[0]["start"]].strip() or None
tool_calls = []
for i, tc in enumerate(completed):
tool_calls.append(
{
"id": f"call_{uuid.uuid4().hex[:12]}",
"type": "function",
"function": {
"name": tc["name"],
"arguments": tc["args"],
},
}
)
return {"content": content, "tool_calls": tool_calls}
@property
def has_tool_calls(self) -> bool:
return self._has_tool_calls