从异步钩子 HTTPINCOMINGMESSAGE 获取 HTTP 标头/正文

问题描述

我正在尝试从异步钩子 IncomingMessage 提供的 HTTPINCOMINGMESSAGE 实例中获取 HTTP 标头和 HTTP 正文：

import asyncHooks = require("async_hooks");
import { IncomingMessage } from "http";

asyncHooks.createHook({
  init: (
    asyncId: number,type: string,triggerAsyncId: number,req: IncomingMessage
  ) => {
    if (type !== "HTTPINCOMINGMESSAGE") return;

    // Where are the HTTP headers?
    console.log(req.headers); // prints `undefined`

    // How do I get the HTTP body?
    console.log(req.on); // prints `undefined`

    // Yet,`req` is an `IncomingMessage`,the same than following `req`:
    //
    //   const http = require('http');
    //   http.createServer((req,res) => {
    //     // The HTTP request headers are available here!
    //     console.log(req.headers);
    //     // `req` is an `IncomingMessage` as well
    //     console.log(req.constructor===IncomingMessage); // prints `true`
    //   });
    //
    console.log(req.constructor===IncomingMessage); // prints `true`
  },})
.enable();

我已经深入研究了 Node.js 源代码，但没有运气。我找不到填充 req.headers 的代码，也找不到创建 HTTP 正文流的代码。

编辑

总体目标是使 Wildcard API 能够提供context：

import { context } from '@wildcard-api/server';

// Wildcard saves a cookie on behaf of the Wildcard user,and exposes
// the value saved in the cookie over an ES6 proxy `context`.

function called_somewhere_within_an_HTTP_Request_lifecycle() {
  // Wildcard uses Async Hooks to be able to kNow the HTTP request associated
  // with the following `context.userName` ES6 proxy getter call,and therefore
  // can provide the value `userName` saved in the cookie of the HTTP request.
  console.log(context.userName);
}

解决方法

不应使用异步钩子来修改程序行为。创建此 API 是为了跟踪异步资源，例如来衡量绩效。尝试以这种方式修改程序会导致未定义的行为和不可预测的错误。

您可以对 NodeJS 的 HTTP 库进行猴子补丁，但我强烈建议您避免使用它。

nodejs-server nodejs-stream