关于python:为-fastapi-添加请求id

为了做日志跟踪，咱们能够用上面的方法来搞一个 request_id 或者说 correlation_id 的货色。

main.py

import sys
import uvicorn
import logging
from uuid import uuid4
from loguru import logger
from fastapi import FastAPI
from fastapi import Request
from typing import Optional
from contextvars import ContextVar


correlation_id: ContextVar[Optional[str]] = ContextVar('correlation_id', default=None)

app = FastAPI()


@app.middleware("http")
async def add_request_id_header(request: Request, call_next):
    correlation_id.set(uuid4().hex)
    response = await call_next(request)

    response.headers["x-request-id"] = correlation_id.get()
    return response


logger.remove()


def correlation_id_filter(record):
    record['correlation_id'] = correlation_id.get()
    return record['correlation_id']


fmt = "<green>{time:YYYY-MM-DD HH:mm:ss.SSS}</green> | <level>{level: <8}</level> | <red> {correlation_id} </red> | <cyan>{name}</cyan>:<cyan>{function}</cyan>:<cyan>{line}</cyan> - <level>{message}</level>"


logger.add(sys.stderr, format=fmt, level=logging.DEBUG,
           filter=correlation_id_filter)


@app.get('/')
def index():
    logger.info(f"Request with id")
    return 'OK'


if __name__ == "__main__":
    uvicorn.run(app="main:app", host="0.0.0.0", port=8000)

应用上面的命令运行程序：

python main.py

用上面的命令发动 http 申请来做测试

http http://localhost:8000/  -v

能够应用 apt install httpie 或者 brew install httpie 来装置 http 命令

输入如下：

GET / HTTP/1.1
Accept: */*
Accept-Encoding: gzip, deflate
Connection: keep-alive
Host: localhost:8000
User-Agent: HTTPie/2.6.0



HTTP/1.1 200 OK
content-length: 4
content-type: application/json
date: Mon, 21 Feb 2022 13:36:50 GMT
server: uvicorn
x-request-id: a27b3b26382545e9ae15358a321a9568

"OK"

事实上，曾经有相应的开源实现了：snok/asgi-correlation-id