Files
my-v0-server/app/observability/tracing.py
T

294 lines
10 KiB
Python

"""一次大屏图调用的 Langfuse 追踪
不属于处理管道的任一步。把图调用收成可过滤的 trace,并把 Jev 记成当前节点下的 evaluator
每轮调用单独记录,首次请求与澄清恢复通过 session 关联,不修改业务状态
"""
from __future__ import annotations
import os
from asyncio import CancelledError
from collections.abc import Iterator
from contextlib import contextmanager
from typing import Any
from loguru import logger
from app.config import settings
# 面板 Trace Name 列用的稳定名字,不要拼 thread_id 或用户原文
TRACE_NAME = "screen-instruct"
# 按功能过滤用的 tag,不是每一次请求的动态标签
FEATURE_TAG = "screen-agent"
# 客户端复用连接;callback 按调用创建,不保留跨请求的恢复关联
_client: Any = None
_unavailable = False
def tracing_enabled() -> bool:
"""三项连接配置都有,且没有显式关掉,才发送 trace
LANGFUSE_TRACING_ENABLED=false 用来本地临时关闭,缺任何一项连接配置也视为关闭
"""
flag = os.getenv("LANGFUSE_TRACING_ENABLED", "").strip().lower()
if flag in {"0", "false", "no"}:
return False
return bool(
os.getenv("LANGFUSE_PUBLIC_KEY", "").strip()
and os.getenv("LANGFUSE_SECRET_KEY", "").strip()
and os.getenv("LANGFUSE_BASE_URL", "").strip()
)
def flush_tracing() -> None:
"""把还在内存里的 span 立刻发出去
Langfuse 默认攒一批再发。演示脚本马上退出时不调用,这条 trace 会丢
追踪没启用或客户端没建成时直接返回,不报错
"""
client = _client
if client is None or _unavailable:
return
try:
client.flush()
except Exception as exc: # noqa: BLE001 追踪故障不阻断业务
logger.opt(exception=exc).warning("Langfuse flush 失败")
async def astream_screen(
graph, payload, *, thread_id, session_id=None, user_id=None, context=None
):
"""同一轮流保持同一个追踪上下文,关闭流时结束追踪;context 是图的运行上下文,不进检查点"""
from contextlib import aclosing
result = {}
with _screen_trace(payload, thread_id, session_id, user_id) as (config, root):
async with aclosing(
graph.astream(
payload,
config=config,
context=context,
stream_mode=["custom", "values"],
)
) as events:
async for mode, data in events:
if mode == "values":
result = data
yield mode, data
_finish_trace(root, result)
def _finish_trace(root, result):
if root is not None:
output = _run_output(result)
root.update(
output=output, level="ERROR" if output["outcome"] == "failed" else "DEFAULT"
)
@contextmanager
def _screen_trace(payload, thread_id, session_id, user_id=None):
config = {"configurable": {"thread_id": thread_id}}
client = _ensure_client() if tracing_enabled() else None
if client is None:
yield config, None
return
from langfuse import propagate_attributes
from langfuse.langchain import CallbackHandler
from langgraph.types import Command
# 明确回调所属项目,避免进程中存在多个客户端时跳过追踪
handler = CallbackHandler(public_key=os.getenv("LANGFUSE_PUBLIC_KEY"))
# 在当前异步上下文执行回调,手动记录的 Jev 观测才会挂到所属节点。
handler.run_inline = True
resume = isinstance(payload, Command) and payload.resume is not None
trace_input = (
{"reply": payload.resume}
if resume
else {"prompt": payload.get("request", {}).get("prompt")}
)
with (
client.start_as_current_observation(
name=TRACE_NAME,
as_type="span",
input=trace_input,
) as root,
propagate_attributes(
trace_name=TRACE_NAME,
session_id=session_id or thread_id,
# 用户中心的 user_id,面板 Users 页按用户聚合;脚本调用没有用户时不设
user_id=str(user_id) if user_id is not None else None,
tags=[FEATURE_TAG],
metadata={
"thread_id": thread_id,
"phase": "resume" if resume else "request",
},
),
):
try:
yield (
{**config, "callbacks": [handler], "run_name": "run-screen-graph"},
root,
)
except (CancelledError, GeneratorExit):
root.update(output={"outcome": "cancelled"})
raise
except Exception as error:
root.update(
output={"outcome": "failed", "error_type": type(error).__name__},
level="ERROR",
status_message=str(error),
)
raise
def _run_output(state: dict[str, Any]) -> dict[str, Any]:
"""记录本轮结束原因;completed 表示图已返回,不代表前端应用了动作。"""
pending = state.get("__interrupt__")
outcome = "completed"
if pending:
outcome = "waiting_for_user"
elif state.get("status") in {"failed", "cancelled"}:
outcome = state["status"]
return {
"outcome": outcome,
"intent": state.get("intent"),
"answer": state.get("answer"),
"clarification": [item.value for item in pending] if pending else None,
"actions": state.get("actions"),
}
@contextmanager
def observe_decision(request: Any) -> Iterator[Any]:
"""在当前节点下面记一次 Jev 调用,yield 的是观测对象,未追踪时是 None
TypeSafe 不走 LangChain callback,所以要手记。类型不能是 generation:会话视图只用 generation
拼对话,且只显示最浅的一条对话线,Jev 比 agent 的模型调用浅,用 generation 会把真正的对话挤掉
只有图回调已经挂上当前 span 时才记。没有父 span 就跳过,避免 Jev 单独变成一条 trace
这里不吞异常:失败时标 ERROR 后原样抛出,调用方的 DecisionError 类型不变
"""
client = _ensure_client() if tracing_enabled() else None
if client is None or not _has_active_span():
yield None
return
model = request.model or settings.typesafe_model
name = "classify-intent" if set(request.decisions) == {"intent"} else "run-decision"
# 复用本应用已经选定的客户端
with client.start_as_current_observation(
as_type="evaluator",
name=name,
model=model,
input={
"questions": {
name: question.model_dump(mode="json")
for name, question in request.decisions.items()
},
"state": request.state,
},
) as observation:
try:
yield observation
except Exception as error:
observation.update(
level="ERROR",
status_message=str(error),
metadata=_error_metadata(error),
)
raise
def record_decision(observation: Any, response: Any) -> None:
"""把成功的 Jev 结果写回刚才那条观测
observation 为 None 表示这次没追踪,直接返回,不影响判断结果
只写选项、置信度和 token。不写原始 HTTP 响应
"""
if observation is None:
return
# evaluator 没有 model/usage 字段,模型和 token 只能放 metadata
metadata = {"model": response.model, "request_id": response.request_id or ""}
if response.usage.input_tokens is not None:
metadata["input_tokens"] = str(response.usage.input_tokens)
if response.usage.output_tokens is not None:
metadata["output_tokens"] = str(response.usage.output_tokens)
observation.update(
output={
name: _result_summary(result) for name, result in response.results.items()
},
metadata=metadata,
)
def _ensure_client() -> Any:
"""第一次使用时建客户端
必须在 load_dotenv 之后调用。初始化失败就记一次警告,本进程后续不再重试
不要在业务失败时调用,追踪不可用不能挡住图执行
"""
global _client, _unavailable
if _unavailable:
return None
if _client is not None:
return _client
os.environ.setdefault("LANGFUSE_TRACING_ENVIRONMENT", "development")
from langfuse import Langfuse
try:
client = Langfuse()
except Exception as exc: # noqa: BLE001 追踪故障不阻断业务
_unavailable = True
logger.opt(exception=exc).warning("Langfuse 不可用,本进程跳过追踪")
return None
_client = client
return client
def _has_active_span() -> bool:
"""当前调用栈上有没有 Langfuse 已经打开的 span
图回调会在节点执行期间挂上 span。没有的话,Jev 不该自己开一条 trace
"""
from opentelemetry import trace
return trace.get_current_span().get_span_context().is_valid
def _result_summary(result: Any) -> dict[str, Any]:
"""按决策题类型抽出面板上要看的字段,不回写原始协议对象"""
summary: dict[str, Any] = {"type": result.type}
if result.type == "choice":
summary["choice"] = result.choice
summary["confidence"] = result.confidence
summary["probabilities"] = result.probabilities
elif result.type == "score":
summary["score"] = result.score
summary["confidence"] = result.confidence
elif result.type == "noul":
summary["noul"] = result.noul
return summary
def _error_metadata(error: BaseException) -> dict[str, str]:
"""失败时附上错误种类和 request_id,方便和 Jev 服务端对日志
只取已经整理过的安全字段,不把请求体或密钥写进 metadata
"""
metadata = {"error_type": type(error).__name__}
kind = getattr(error, "kind", None)
request_id = getattr(error, "request_id", None)
status = getattr(error, "status", None)
if isinstance(kind, str):
metadata["kind"] = kind
if isinstance(request_id, str):
metadata["request_id"] = request_id
if isinstance(status, int):
metadata["status"] = str(status)
return metadata