autoproxy

autoproxy is a local HTTPS proxy relay written in Node.js.

中文文档: README.zh-CN.md

It fetches public proxies from https://free-proxy-list.net/en/, keeps only entries where both Google = yes and Https = yes, and forwards incoming CONNECT requests to the filtered upstream proxy pool.

⚠️ For Learning and Research Purposes Only

This project is intended solely as a learning exercise and technical demonstration. Free public proxies are inherently untrusted third-party servers — they may be unstable, inject malicious content, intercept traffic, or go offline without notice. Never use this project to handle sensitive data, credentials, or any production workload.

If you need a reliable proxy for real-world use, please purchase a trustworthy commercial proxy service.

The author(s) of this project accept no responsibility or liability for any loss, damage, security incident, legal issue, or other consequence arising directly or indirectly from the use of this software.

Features

• Auto-fetch proxy list from free-proxy-list.net/en/
• Filter by:
  • Google = yes
  • Https = yes
• Auto-refresh proxy pool on a fixed interval
• Local proxy listener on port 2319 by default
• HTTPS tunneling via CONNECT with fallback to next upstream proxy

How It Works

1. On startup, the service fetches and parses the proxy table HTML.
2. It extracts and deduplicates IP:Port entries that match the filter rules.
3. It listens for local proxy client traffic.
4. For each CONNECT host:port request, it tries upstream proxies in a round-robin candidate order.
5. On the first successful upstream tunnel (HTTP 200), it starts full duplex socket piping between client and upstream.
6. A background timer keeps refreshing the proxy pool so list updates are applied automatically.

Project Structure

.
|- index.js
|- package.json
|- README.md
|- README.zh-CN.md
`- LICENSE

Requirements

• Node.js 18+ (LTS recommended)

Install and Run

npm install
npm start

Or run directly:

node index.js

Default listener:

0.0.0.0:2319

Configuration

All options are configurable with environment variables:

• PORT: local listen port, default 2319
• REFRESH_INTERVAL_MS: proxy refresh interval in milliseconds, default 60000
• MIN_REFRESH_GAP_MS: minimum allowed refresh gap in milliseconds, default 15000
• CONNECT_TIMEOUT_MS: upstream connect timeout in milliseconds, default 10000

PowerShell example:

$env:PORT=2319
$env:REFRESH_INTERVAL_MS=45000
$env:CONNECT_TIMEOUT_MS=8000
node index.js

Usage

Point your program's HTTPS proxy to 127.0.0.1:2319.

Example with curl:

curl -x http://127.0.0.1:2319 https://www.google.com -I

Notes:

• This service supports HTTPS tunneling via CONNECT.
• Regular HTTP proxying is not implemented and returns 405.

Logs

Typical logs:

• Refresh log:
  • [refresh] ... loaded N proxies
  • [refresh] ... failed: <reason>
• Connect log:
  • [connect] targetHost:targetPort via proxyHost:proxyPort

These logs help confirm whether pool refresh is healthy and whether traffic is actually relayed through upstream proxies.

Troubleshooting

1. Refresh failures such as EACCES or ETIMEDOUT
   • Usually means network access from current runtime is restricted.
2. Proxy pool is empty
   • No matching entries were parsed, or source HTML structure changed.
3. 502 Bad Gateway
   • All candidate upstream proxies failed for this connection attempt.

Security and Disclaimer

• Free public proxies are inherently unstable and risky. They are operated by unknown third parties and may snoop on, tamper with, or drop your traffic at any time.
• This project is for learning purposes only. Do not use it for sensitive, personal, or production-critical traffic.
• For production use, please purchase a reputable commercial proxy service instead of relying on free public proxies.
• The author(s) disclaim all liability for any damage, data loss, security breach, or legal consequence resulting from the use of this software. Use at your own risk.
• Make sure your use complies with applicable laws and target-site terms of service.

License

This project is licensed under the MIT License. See LICENSE.