ProxyAgent: support socks5 protocol

[idranme]

This would solve...

Using the socks5 proxy.

The implementation should look like...

import { ProxyAgent } from 'undici'
const client = new ProxyAgent('socks5://127.0.0.1:7890/')

I have also considered...

Additional context

[mcollina]

This would be amazing, but it'd also be somewhat feasible to create it outside of this module. I recommend that route at this point as we are stretched really thin.

[idranme]

It would be best if it could be integrated in this module.

[mcollina]

PRs are welcomed.

[KhafraDev]

have you tried https://github.com/Kaciras/fetch-socks?

[idranme]

have you tried https://github.com/Kaciras/fetch-socks?

https://github.com/Kaciras/fetch-socks/blob/master/package.json#L34

This package depends on an undici. So I don't think it's ideal.

[KhafraDev]

the caret means it supports undici versions of at least 5.22.1

[idranme]

the caret means it supports undici versions of at least 5.22.1

When I use undici, it installs one more on its side, which will now will exist two undici.

[KhafraDev]

you can probably use dedupe

[PandaWorker]

Wouldn't it be simpler to make a buildConnector for each type of proxy and use it as a connector?

const httpProxyBuildConnector = (proxy) => {
 return (opts) => {
    const socket = createConnection(opts);
    return socket;
  }
}

const socksProxyBuildConnector = (proxy) => {
  return (opts) => {
    const socket = createConnection(opts);
    return socket;
  }
}

const proxyConnector = httpProxyBuildConnector(proxy);
const proxyAgent = new Agent({connect: proxyConnector });

const resp = await fetch('localhost:3000/', {
  dispatcher: proxyAgent
});

Or you can do it the same way as done by aiohttp in python (https://github.com/Slzdude/aiohttp-proxy)

[eugenepugach]

Also after implementation SOCKS5 - we have got CRITICAL Vulnerability ❌ CVE-2023-38545 which affected on the security.

[joyeecheung]

If no one is working on it I am interested in picking it up, as I am working on nodejs/node#57165 I think it would be a great addition for Node.js built fetch to work more seamlessly with socks 5 proxies. The lack of support of it was one of the reasons I added the local README config in node-core-utils as a workaround (because if you try to fetch github raw content within Chinese GFW you get connection issues). It would also help closing nodejs/node-core-utils#653 and overall making Node.js easier to use for developers in China (socks5 is very popular in China).