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zk-data-agent/src/openai_compat.py
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from __future__ import annotations
import json
import os
from typing import Any, Iterator
from urllib import error, request
from .agent_types import (
AssistantTurn,
ModelConfig,
OutputSchemaConfig,
StreamEvent,
ToolCall,
UsageStats,
)
class OpenAICompatError(RuntimeError):
"""Raised when the local OpenAI-compatible backend returns an invalid response."""
PROVIDER_MIN_TEMPERATURES = {
# 实测这些 provider 会拒绝 temperature=0;这里做最小值兜底,
# 保持默认确定性取向的同时避免模型切换后请求直接 400。
'minimax': 0.01,
'wenxin': 0.1,
}
ANTHROPIC_MESSAGES_MODEL_PREFIXES = (
'ppio/pa/claude-',
)
ANTHROPIC_VERSION = '2023-06-01'
ANTHROPIC_MAX_TOKENS = 4096
DEFAULT_MODEL_IDLE_TIMEOUT_SECONDS = 60.0
def _join_url(base_url: str, suffix: str) -> str:
base = base_url.rstrip('/')
return f'{base}/{suffix.lstrip("/")}'
def _normalize_content(content: Any) -> str:
if content is None:
return ''
if isinstance(content, str):
return content
if isinstance(content, list):
parts: list[str] = []
for item in content:
if isinstance(item, str):
parts.append(item)
continue
if not isinstance(item, dict):
parts.append(str(item))
continue
if item.get('type') == 'text' and isinstance(item.get('text'), str):
parts.append(item['text'])
continue
if isinstance(item.get('text'), str):
parts.append(item['text'])
continue
parts.append(json.dumps(item, ensure_ascii=True))
return ''.join(parts)
return str(content)
def _parse_tool_arguments(raw_arguments: Any) -> dict[str, Any]:
if raw_arguments is None:
return {}
if isinstance(raw_arguments, dict):
return raw_arguments
if isinstance(raw_arguments, str):
raw_arguments = raw_arguments.strip()
if not raw_arguments:
return {}
try:
parsed = json.loads(raw_arguments)
except json.JSONDecodeError as exc:
preview = raw_arguments[:240].replace('\n', '\\n')
raise OpenAICompatError(
'Invalid tool arguments returned by model: '
f'line {exc.lineno} column {exc.colno}: {exc.msg}; '
f'preview={preview!r}'
) from exc
if not isinstance(parsed, dict):
raise OpenAICompatError(
f'Tool arguments must decode to an object, got {type(parsed).__name__}'
)
return parsed
raise OpenAICompatError(
f'Unsupported tool arguments payload: {type(raw_arguments).__name__}'
)
def _tool_call_ids(message: dict[str, Any]) -> list[str]:
raw_tool_calls = message.get('tool_calls')
if not isinstance(raw_tool_calls, list):
return []
ids: list[str] = []
for index, raw_call in enumerate(raw_tool_calls):
if not isinstance(raw_call, dict):
continue
call_id = raw_call.get('id')
ids.append(call_id if isinstance(call_id, str) and call_id else f'call_{index}')
return ids
def _contiguous_tool_result_ids(
messages: list[dict[str, Any]],
start_index: int,
) -> set[str]:
ids: set[str] = set()
index = start_index
while index < len(messages) and messages[index].get('role') == 'tool':
tool_call_id = messages[index].get('tool_call_id')
if isinstance(tool_call_id, str) and tool_call_id:
ids.add(tool_call_id)
index += 1
return ids
def _filter_tool_calls_by_ids(
message: dict[str, Any],
valid_ids: set[str],
) -> dict[str, Any]:
raw_tool_calls = message.get('tool_calls')
if not isinstance(raw_tool_calls, list):
return message
filtered: list[dict[str, Any]] = []
for index, raw_call in enumerate(raw_tool_calls):
if not isinstance(raw_call, dict):
continue
call_id = raw_call.get('id')
normalized_id = (
call_id if isinstance(call_id, str) and call_id else f'call_{index}'
)
if normalized_id in valid_ids:
filtered.append(raw_call)
if len(filtered) == len(raw_tool_calls):
return message
next_message = dict(message)
if filtered:
next_message['tool_calls'] = filtered
else:
next_message.pop('tool_calls', None)
return next_message
def _sanitize_anthropic_tool_messages(
messages: list[dict[str, Any]],
) -> list[dict[str, Any]]:
"""清理 Anthropic/Bedrock 严格要求的 tool_use/tool_result 邻接关系。
OpenAI 风格历史在异常中断、裁剪或前端恢复时可能留下 assistant tool_calls
但下一条消息不再紧跟对应 tool 结果。Anthropic Messages API 会直接拒绝
这种历史。这里在出网关前删除缺失结果的 tool_call,并跳过没有前置
tool_use 的孤儿 tool 结果,保留普通文本上下文继续对话。
"""
sanitized: list[dict[str, Any]] = []
pending_tool_ids: set[str] = set()
for index, message in enumerate(messages):
role = message.get('role')
if role == 'assistant':
tool_ids = _tool_call_ids(message)
if tool_ids:
result_ids = _contiguous_tool_result_ids(messages, index + 1)
valid_ids = set(tool_ids).intersection(result_ids)
message = _filter_tool_calls_by_ids(message, valid_ids)
pending_tool_ids = valid_ids
else:
pending_tool_ids = set()
sanitized.append(message)
continue
if role == 'tool':
tool_call_id = message.get('tool_call_id')
if isinstance(tool_call_id, str) and tool_call_id in pending_tool_ids:
sanitized.append(message)
continue
pending_tool_ids = set()
sanitized.append(message)
return sanitized
def _optional_int(value: Any) -> int:
if isinstance(value, bool):
return 0
if isinstance(value, int):
return value
if isinstance(value, float):
return int(value)
if isinstance(value, str):
try:
return int(value)
except ValueError:
return 0
return 0
def _temperature_for_model(model: str, configured: float) -> float:
provider = model.split('/', 1)[0].strip().lower() if '/' in model else ''
minimum = PROVIDER_MIN_TEMPERATURES.get(provider)
if minimum is None:
return configured
return max(configured, minimum)
def _uses_anthropic_messages_api(model: str, base_url: str) -> bool:
normalized_model = model.strip().lower()
normalized_base = base_url.rstrip('/').lower()
return normalized_base.endswith('/anthropic') or any(
normalized_model.startswith(prefix)
for prefix in ANTHROPIC_MESSAGES_MODEL_PREFIXES
)
def _anthropic_base_url(base_url: str) -> str:
base = base_url.rstrip('/')
if base.lower().endswith('/anthropic'):
return base
if base.lower().endswith('/v1'):
return f'{base[:-3]}/anthropic'
return f'{base}/anthropic'
def _parse_usage(payload: Any) -> UsageStats:
if not isinstance(payload, dict):
return UsageStats()
completion_details = payload.get('completion_tokens_details')
if not isinstance(completion_details, dict):
completion_details = {}
return UsageStats(
input_tokens=(
_optional_int(payload.get('input_tokens'))
or _optional_int(payload.get('prompt_tokens'))
or _optional_int(payload.get('prompt_eval_count'))
),
output_tokens=(
_optional_int(payload.get('output_tokens'))
or _optional_int(payload.get('completion_tokens'))
or _optional_int(payload.get('eval_count'))
),
cache_creation_input_tokens=_optional_int(
payload.get('cache_creation_input_tokens')
),
cache_read_input_tokens=_optional_int(payload.get('cache_read_input_tokens')),
reasoning_tokens=(
_optional_int(payload.get('reasoning_tokens'))
or _optional_int(completion_details.get('reasoning_tokens'))
),
)
def _build_response_format(
schema: OutputSchemaConfig | None,
) -> dict[str, Any] | None:
if schema is None:
return None
return {
'type': 'json_schema',
'json_schema': {
'name': schema.name,
'schema': schema.schema,
'strict': schema.strict,
},
}
class OpenAICompatClient:
"""Minimal OpenAI-compatible chat client for local model servers."""
def __init__(self, config: ModelConfig) -> None:
self.config = config
def _request_timeout_seconds(self) -> float:
"""Return per-socket model timeout.
`ModelConfig.timeout_seconds` is the whole request budget used by the
product, but urllib applies it as an idle socket timeout. Keeping it at
one hour makes a bad upstream stream hold a session lock for an hour.
Use a shorter idle timeout by default; any normally streaming response
keeps extending this naturally because bytes continue to arrive.
"""
raw = os.environ.get('CLAW_MODEL_IDLE_TIMEOUT_SECONDS', '').strip()
try:
configured = float(raw) if raw else DEFAULT_MODEL_IDLE_TIMEOUT_SECONDS
except ValueError:
configured = DEFAULT_MODEL_IDLE_TIMEOUT_SECONDS
configured = max(5.0, configured)
return min(float(self.config.timeout_seconds), configured)
def complete(
self,
messages: list[dict[str, Any]],
tools: list[dict[str, Any]],
*,
output_schema: OutputSchemaConfig | None = None,
) -> AssistantTurn:
if self._uses_anthropic_messages_api():
return self._complete_anthropic_messages(
messages=messages,
tools=tools,
output_schema=output_schema,
)
payload = self._request_json(
self._build_payload(
messages=messages,
tools=tools,
stream=False,
output_schema=output_schema,
)
)
choices = payload.get('choices')
if not isinstance(choices, list) or not choices:
raise OpenAICompatError('Local model backend returned no choices')
first_choice = choices[0]
if not isinstance(first_choice, dict):
raise OpenAICompatError('Local model backend returned malformed choice data')
message = first_choice.get('message')
if not isinstance(message, dict):
raise OpenAICompatError('Local model backend returned no assistant message')
content = _normalize_content(message.get('content'))
tool_calls = self._parse_tool_calls_from_message(message)
finish_reason = first_choice.get('finish_reason')
if finish_reason is not None and not isinstance(finish_reason, str):
finish_reason = str(finish_reason)
return AssistantTurn(
content=content,
tool_calls=tuple(tool_calls),
finish_reason=finish_reason,
raw_message=message,
usage=_parse_usage(payload.get('usage')),
)
def stream(
self,
messages: list[dict[str, Any]],
tools: list[dict[str, Any]],
*,
output_schema: OutputSchemaConfig | None = None,
) -> Iterator[StreamEvent]:
if self._uses_anthropic_messages_api():
yield from self._stream_anthropic_messages(
messages=messages,
tools=tools,
output_schema=output_schema,
)
return
payload = self._build_payload(
messages=messages,
tools=tools,
stream=True,
output_schema=output_schema,
)
req = request.Request(
_join_url(self.config.base_url, '/chat/completions'),
data=json.dumps(payload).encode('utf-8'),
headers={
'Authorization': f'Bearer {self.config.api_key}',
'Content-Type': 'application/json',
},
method='POST',
)
try:
with request.urlopen(req, timeout=self._request_timeout_seconds()) as response:
yield StreamEvent(type='message_start')
for event_payload in self._iter_sse_payloads(response):
yield from self._parse_stream_payload(event_payload)
except error.HTTPError as exc:
detail = exc.read().decode('utf-8', errors='replace')
raise OpenAICompatError(
f'HTTP {exc.code} from local model backend: {detail}'
) from exc
except error.URLError as exc:
raise OpenAICompatError(
f'Unable to reach local model backend at {self.config.base_url}: {exc.reason}'
) from exc
def _uses_anthropic_messages_api(self) -> bool:
return _uses_anthropic_messages_api(self.config.model, self.config.base_url)
def _request_json(self, payload: dict[str, Any]) -> dict[str, Any]:
body = json.dumps(payload).encode('utf-8')
req = request.Request(
_join_url(self.config.base_url, '/chat/completions'),
data=body,
headers={
'Authorization': f'Bearer {self.config.api_key}',
'Content-Type': 'application/json',
},
method='POST',
)
try:
with request.urlopen(req, timeout=self._request_timeout_seconds()) as response:
raw = response.read()
except error.HTTPError as exc:
detail = exc.read().decode('utf-8', errors='replace')
raise OpenAICompatError(
f'HTTP {exc.code} from local model backend: {detail}'
) from exc
except error.URLError as exc:
raise OpenAICompatError(
f'Unable to reach local model backend at {self.config.base_url}: {exc.reason}'
) from exc
try:
payload = json.loads(raw.decode('utf-8'))
except json.JSONDecodeError as exc:
raise OpenAICompatError('Local model backend returned invalid JSON') from exc
if not isinstance(payload, dict):
raise OpenAICompatError('Local model backend returned malformed JSON payload')
return payload
def _build_payload(
self,
*,
messages: list[dict[str, Any]],
tools: list[dict[str, Any]],
stream: bool,
output_schema: OutputSchemaConfig | None,
) -> dict[str, Any]:
payload: dict[str, Any] = {
'model': self.config.model,
'messages': messages,
'temperature': _temperature_for_model(self.config.model, self.config.temperature),
'stream': stream,
}
if tools:
payload['tools'] = tools
payload['tool_choice'] = 'auto'
if stream:
payload['stream_options'] = {'include_usage': True}
response_format = _build_response_format(output_schema)
if response_format is not None:
payload['response_format'] = response_format
return payload
def _build_anthropic_payload(
self,
*,
messages: list[dict[str, Any]],
tools: list[dict[str, Any]],
stream: bool,
output_schema: OutputSchemaConfig | None,
) -> dict[str, Any]:
system_parts: list[str] = []
anthropic_messages: list[dict[str, Any]] = []
for message in _sanitize_anthropic_tool_messages(messages):
role = message.get('role')
if role == 'system':
content = _normalize_content(message.get('content')).strip()
if content:
system_parts.append(content)
continue
if role == 'assistant':
blocks = self._anthropic_assistant_blocks(message)
if blocks:
self._append_anthropic_message(anthropic_messages, 'assistant', blocks)
continue
if role == 'tool':
tool_call_id = message.get('tool_call_id')
if not isinstance(tool_call_id, str) or not tool_call_id:
tool_call_id = 'toolu_unknown'
self._append_anthropic_message(
anthropic_messages,
'user',
[
{
'type': 'tool_result',
'tool_use_id': tool_call_id,
'content': _normalize_content(message.get('content')),
}
],
)
continue
if role == 'user':
blocks = self._anthropic_text_blocks(message.get('content'))
if blocks:
self._append_anthropic_message(anthropic_messages, 'user', blocks)
payload: dict[str, Any] = {
'model': self.config.model,
'messages': anthropic_messages,
'max_tokens': ANTHROPIC_MAX_TOKENS,
'stream': stream,
}
if system_parts:
payload['system'] = '\n\n'.join(system_parts)
converted_tools = self._anthropic_tools(tools)
if converted_tools:
payload['tools'] = converted_tools
if output_schema is not None:
schema_hint = (
f'请严格输出符合 JSON Schema `{output_schema.name}` 的 JSON'
'不要输出额外解释。'
)
payload['system'] = (
f'{payload.get("system", "")}\n\n{schema_hint}'.strip()
)
return payload
def _anthropic_headers(self) -> dict[str, str]:
return {
'Authorization': f'Bearer {self.config.api_key}',
'Content-Type': 'application/json',
'anthropic-version': ANTHROPIC_VERSION,
'api-key': self.config.api_key,
'x-api-key': self.config.api_key,
}
def _anthropic_messages_url(self) -> str:
return _join_url(_anthropic_base_url(self.config.base_url), '/v1/messages')
def _complete_anthropic_messages(
self,
*,
messages: list[dict[str, Any]],
tools: list[dict[str, Any]],
output_schema: OutputSchemaConfig | None,
) -> AssistantTurn:
payload = self._build_anthropic_payload(
messages=messages,
tools=tools,
stream=False,
output_schema=output_schema,
)
body = json.dumps(payload).encode('utf-8')
req = request.Request(
self._anthropic_messages_url(),
data=body,
headers=self._anthropic_headers(),
method='POST',
)
try:
with request.urlopen(req, timeout=self._request_timeout_seconds()) as response:
raw = response.read()
except error.HTTPError as exc:
detail = exc.read().decode('utf-8', errors='replace')
raise OpenAICompatError(
f'HTTP {exc.code} from local model backend: {detail}'
) from exc
except error.URLError as exc:
raise OpenAICompatError(
f'Unable to reach local model backend at {self.config.base_url}: {exc.reason}'
) from exc
try:
response_payload = json.loads(raw.decode('utf-8'))
except json.JSONDecodeError as exc:
raise OpenAICompatError('Local model backend returned invalid JSON') from exc
if not isinstance(response_payload, dict):
raise OpenAICompatError('Local model backend returned malformed JSON payload')
return self._parse_anthropic_message_response(response_payload)
def _stream_anthropic_messages(
self,
*,
messages: list[dict[str, Any]],
tools: list[dict[str, Any]],
output_schema: OutputSchemaConfig | None,
) -> Iterator[StreamEvent]:
payload = self._build_anthropic_payload(
messages=messages,
tools=tools,
stream=True,
output_schema=output_schema,
)
req = request.Request(
self._anthropic_messages_url(),
data=json.dumps(payload).encode('utf-8'),
headers=self._anthropic_headers(),
method='POST',
)
try:
with request.urlopen(req, timeout=self._request_timeout_seconds()) as response:
yield StreamEvent(type='message_start')
tool_block_indexes: dict[int, int] = {}
next_tool_index = 0
finish_reason: str | None = None
for event_payload in self._iter_sse_payloads(response):
event_type = event_payload.get('type')
if event_type == 'message_start':
message = event_payload.get('message')
usage = _parse_usage(
message.get('usage') if isinstance(message, dict) else None
)
if usage.total_tokens:
yield StreamEvent(
type='usage',
usage=usage,
raw_event=event_payload,
)
continue
if event_type == 'content_block_start':
block_index = event_payload.get('index')
content_block = event_payload.get('content_block')
if not isinstance(block_index, int) or not isinstance(content_block, dict):
continue
if content_block.get('type') != 'tool_use':
continue
tool_index = next_tool_index
next_tool_index += 1
tool_block_indexes[block_index] = tool_index
tool_input = content_block.get('input')
arguments = (
json.dumps(tool_input, ensure_ascii=True)
if isinstance(tool_input, dict) and tool_input
else ''
)
yield StreamEvent(
type='tool_call_delta',
tool_call_index=tool_index,
tool_call_id=(
content_block.get('id')
if isinstance(content_block.get('id'), str)
else None
),
tool_name=(
content_block.get('name')
if isinstance(content_block.get('name'), str)
else None
),
arguments_delta=arguments,
raw_event=event_payload,
)
continue
if event_type == 'content_block_delta':
delta = event_payload.get('delta')
if not isinstance(delta, dict):
continue
if delta.get('type') == 'text_delta':
text = delta.get('text')
if isinstance(text, str) and text:
yield StreamEvent(
type='content_delta',
delta=text,
raw_event=event_payload,
)
continue
if delta.get('type') == 'input_json_delta':
block_index = event_payload.get('index')
partial_json = delta.get('partial_json')
if (
isinstance(block_index, int)
and block_index in tool_block_indexes
and isinstance(partial_json, str)
and partial_json
):
yield StreamEvent(
type='tool_call_delta',
tool_call_index=tool_block_indexes[block_index],
arguments_delta=partial_json,
raw_event=event_payload,
)
continue
if event_type == 'message_delta':
delta = event_payload.get('delta')
if isinstance(delta, dict) and isinstance(delta.get('stop_reason'), str):
finish_reason = delta['stop_reason']
usage = _parse_usage(event_payload.get('usage'))
if usage.total_tokens:
yield StreamEvent(
type='usage',
usage=usage,
raw_event=event_payload,
)
continue
if event_type == 'message_stop':
yield StreamEvent(
type='message_stop',
finish_reason=finish_reason,
raw_event=event_payload,
)
except error.HTTPError as exc:
detail = exc.read().decode('utf-8', errors='replace')
raise OpenAICompatError(
f'HTTP {exc.code} from local model backend: {detail}'
) from exc
except error.URLError as exc:
raise OpenAICompatError(
f'Unable to reach local model backend at {self.config.base_url}: {exc.reason}'
) from exc
def _parse_anthropic_message_response(self, payload: dict[str, Any]) -> AssistantTurn:
raw_content = payload.get('content')
if not isinstance(raw_content, list):
raise OpenAICompatError('Anthropic backend returned no content blocks')
text_parts: list[str] = []
tool_calls: list[ToolCall] = []
for index, block in enumerate(raw_content):
if not isinstance(block, dict):
continue
if block.get('type') == 'text':
text = block.get('text')
if isinstance(text, str):
text_parts.append(text)
continue
if block.get('type') == 'tool_use':
name = block.get('name')
if not isinstance(name, str) or not name:
raise OpenAICompatError('Tool call missing function name')
call_id = block.get('id')
if not isinstance(call_id, str) or not call_id:
call_id = f'call_{index}'
arguments = block.get('input')
if not isinstance(arguments, dict):
arguments = {}
tool_calls.append(ToolCall(id=call_id, name=name, arguments=arguments))
finish_reason = payload.get('stop_reason')
if finish_reason is not None and not isinstance(finish_reason, str):
finish_reason = str(finish_reason)
return AssistantTurn(
content=''.join(text_parts),
tool_calls=tuple(tool_calls),
finish_reason=finish_reason,
raw_message=payload,
usage=_parse_usage(payload.get('usage')),
)
def _anthropic_assistant_blocks(self, message: dict[str, Any]) -> list[dict[str, Any]]:
blocks: list[dict[str, Any]] = []
content = _normalize_content(message.get('content'))
if content:
blocks.append({'type': 'text', 'text': content})
raw_tool_calls = message.get('tool_calls')
if isinstance(raw_tool_calls, list):
for index, raw_call in enumerate(raw_tool_calls):
if not isinstance(raw_call, dict):
continue
function_block = raw_call.get('function')
if not isinstance(function_block, dict):
continue
name = function_block.get('name')
if not isinstance(name, str) or not name:
continue
call_id = raw_call.get('id')
if not isinstance(call_id, str) or not call_id:
call_id = f'call_{index}'
try:
arguments = _parse_tool_arguments(function_block.get('arguments'))
except OpenAICompatError:
arguments = {}
blocks.append(
{
'type': 'tool_use',
'id': call_id,
'name': name,
'input': arguments,
}
)
return blocks
def _anthropic_text_blocks(self, content: Any) -> list[dict[str, Any]]:
normalized = _normalize_content(content)
if not normalized:
return []
return [{'type': 'text', 'text': normalized}]
def _anthropic_tools(self, tools: list[dict[str, Any]]) -> list[dict[str, Any]]:
converted: list[dict[str, Any]] = []
for tool in tools:
if not isinstance(tool, dict):
continue
function_block = tool.get('function')
if not isinstance(function_block, dict):
continue
name = function_block.get('name')
if not isinstance(name, str) or not name:
continue
entry: dict[str, Any] = {
'name': name,
'input_schema': function_block.get('parameters') or {'type': 'object'},
}
description = function_block.get('description')
if isinstance(description, str) and description:
entry['description'] = description
converted.append(entry)
return converted
def _append_anthropic_message(
self,
messages: list[dict[str, Any]],
role: str,
blocks: list[dict[str, Any]],
) -> None:
if not blocks:
return
if messages and messages[-1].get('role') == role:
previous = messages[-1].get('content')
if isinstance(previous, list):
previous.extend(blocks)
return
messages.append({'role': role, 'content': blocks})
def _parse_tool_calls_from_message(self, message: dict[str, Any]) -> list[ToolCall]:
tool_calls: list[ToolCall] = []
raw_tool_calls = message.get('tool_calls')
if isinstance(raw_tool_calls, list):
for idx, raw_call in enumerate(raw_tool_calls):
if not isinstance(raw_call, dict):
raise OpenAICompatError('Malformed tool call payload from model')
function_block = raw_call.get('function') or {}
if not isinstance(function_block, dict):
raise OpenAICompatError('Malformed tool call function payload from model')
name = function_block.get('name')
if not isinstance(name, str) or not name:
raise OpenAICompatError('Tool call missing function name')
call_id = raw_call.get('id')
if not isinstance(call_id, str) or not call_id:
call_id = f'call_{idx}'
arguments = _parse_tool_arguments(function_block.get('arguments'))
tool_calls.append(ToolCall(id=call_id, name=name, arguments=arguments))
elif isinstance(message.get('function_call'), dict):
function_call = message['function_call']
name = function_call.get('name')
if not isinstance(name, str) or not name:
raise OpenAICompatError('Function call missing name')
arguments = _parse_tool_arguments(function_call.get('arguments'))
tool_calls.append(ToolCall(id='call_0', name=name, arguments=arguments))
return tool_calls
def _iter_sse_payloads(self, response: Any) -> Iterator[dict[str, Any]]:
buffer: list[str] = []
while True:
line = response.readline()
if not line:
break
if isinstance(line, bytes):
text = line.decode('utf-8', errors='replace')
else:
text = str(line)
stripped = text.strip()
if not stripped:
if not buffer:
continue
joined = '\n'.join(buffer)
buffer.clear()
if joined == '[DONE]':
break
try:
payload = json.loads(joined)
except json.JSONDecodeError as exc:
raise OpenAICompatError(
f'Invalid JSON in streaming response: {joined!r}'
) from exc
if not isinstance(payload, dict):
raise OpenAICompatError('Malformed SSE payload from model backend')
yield payload
continue
if stripped.startswith('data:'):
buffer.append(stripped[5:].strip())
if buffer:
joined = '\n'.join(buffer)
if joined != '[DONE]':
try:
payload = json.loads(joined)
except json.JSONDecodeError as exc:
raise OpenAICompatError(
f'Invalid trailing JSON in streaming response: {joined!r}'
) from exc
if not isinstance(payload, dict):
raise OpenAICompatError('Malformed trailing SSE payload from model backend')
yield payload
def _parse_stream_payload(
self,
payload: dict[str, Any],
) -> Iterator[StreamEvent]:
usage = _parse_usage(payload.get('usage'))
if usage.total_tokens:
yield StreamEvent(
type='usage',
usage=usage,
raw_event=payload,
)
choices = payload.get('choices')
if not isinstance(choices, list):
return
for choice in choices:
if not isinstance(choice, dict):
continue
delta = choice.get('delta')
if not isinstance(delta, dict):
delta = {}
content = delta.get('content')
if isinstance(content, str) and content:
yield StreamEvent(
type='content_delta',
delta=content,
raw_event=choice,
)
tool_calls = delta.get('tool_calls')
if isinstance(tool_calls, list):
for raw_tool_call in tool_calls:
if not isinstance(raw_tool_call, dict):
continue
function_block = raw_tool_call.get('function')
if not isinstance(function_block, dict):
function_block = {}
yield StreamEvent(
type='tool_call_delta',
tool_call_index=(
raw_tool_call.get('index')
if isinstance(raw_tool_call.get('index'), int)
else 0
),
tool_call_id=(
raw_tool_call.get('id')
if isinstance(raw_tool_call.get('id'), str)
else None
),
tool_name=(
function_block.get('name')
if isinstance(function_block.get('name'), str)
else None
),
arguments_delta=(
function_block.get('arguments')
if isinstance(function_block.get('arguments'), str)
else ''
),
raw_event=raw_tool_call,
)
finish_reason = choice.get('finish_reason')
if finish_reason is not None:
if not isinstance(finish_reason, str):
finish_reason = str(finish_reason)
yield StreamEvent(
type='message_stop',
finish_reason=finish_reason,
raw_event=choice,
)