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Kohei Ueno
Kohei Ueno

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Packet Sniffing tool implemented in Node.js (alternatives to Charles, hoxy, etc...)

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GitHub logo cola119 / ESniffer

Modern network analyze tool. Alternatives to Hoxy, Charles, etc.

ESniffer 🔬

Modern network analyze tool. Alternatives to Hoxy, Charles, etc.

Install

npm i esniffer
yarn add esniffer

Example

// index.js
import ESniffer from "esniffer";
import fs from "fs";
// Required if you want to monitor over HTTPS
const key = fs.readFileSync(`path/to/root-key.pem`);
const cert = fs.readFileSync(`path/to/root-cert.pem`);
const proxy = ESniffer.createServer({ secure: { key, cert } });
proxy.listen(8080);
proxy.on("request", (req) => {
  req.pipe(process.stdout);
});
proxy.on("response", (res) => {
  res.pipe(process.stdout);
});
proxy.on("info", (info) => {
  console.log(info);
}
…

Charles is an HTTP proxy / HTTP monitor / Reverse Proxy that enables a developer to view all of the HTTP and SSL / HTTPS traffic between their machine and the Internet. I'm a heavy user of Charles for debugging but sometimes struggle with its lack of customization.

If we can monitor HTTP/HTTPS traffic using Node.js script, we can do even more useful debugging and testing. So I've developed a simple module that allows for packet monitoring.

import ESniffer from "esniffer";
import fs from "fs";

// Required if you want to monitor over HTTPS
const key = fs.readFileSync(`path/to/root-key.pem`);
const cert = fs.readFileSync(`path/to/root-cert.pem`);

const proxy = ESniffer.createServer({ secure: { key, cert } });
proxy.listen(8080);

proxy.on("request", (req) => {
  req.pipe(process.stdout);
});
proxy.on("response", (res) => {
  res.pipe(process.stdout);
});
proxy.on("info", (info) => {
  console.log(info);
});
proxy.on("error", (e) => {
  console.error(e.message);
});

This is inheriting the EventEmitter so we can access request to the server and response from the server via custom events. By installing and trusting a self-signed certificate, we can also monitor over HTTPS communication. See examples for more information.

Finally, I welcome bug reports and requests for additional features. Github Star, please!

GitHub logo cola119 / ESniffer

Modern network analyze tool. Alternatives to Hoxy, Charles, etc.

ESniffer 🔬

Modern network analyze tool. Alternatives to Hoxy, Charles, etc.

Install

npm i esniffer
yarn add esniffer

Example

// index.js
import ESniffer from "esniffer";
import fs from "fs";
// Required if you want to monitor over HTTPS
const key = fs.readFileSync(`path/to/root-key.pem`);
const cert = fs.readFileSync(`path/to/root-cert.pem`);
const proxy = ESniffer.createServer({ secure: { key, cert } });
proxy.listen(8080);
proxy.on("request", (req) => {
  req.pipe(process.stdout);
});
proxy.on("response", (res) => {
  res.pipe(process.stdout);
});
proxy.on("info", (info) => {
  console.log(info);
}
…

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