Js-libp2p "peer and content routing" / kad-dht example

5

Thank you again. So I am trying to follow these instructions…

After reading the js-libp2p-websockets README I made a very simple standalone script bounce.js:

// Based on peer-and-content-routing 1.js
/* eslint-disable no-console */
'use strict'

const Libp2p = require('libp2p')
const Websockets = require('libp2p-websockets')
//const WebRTCStar = require('libp2p-webrtc-star')
const Mplex = require('libp2p-mplex')
const { NOISE } = require('libp2p-noise')
const KadDHT = require('libp2p-kad-dht')

const delay = require('delay')

const createNode = async () => {
  const node = await Libp2p.create({
    addresses: {
      listen: ['/ip4/0.0.0.0/tcp/10001/ws']
    },
    modules: {
      transport: [Websockets],
      streamMuxer: [Mplex],
      connEncryption: [NOISE],
      dht: KadDHT
    },
    config: {
      dht: {
        enabled: true
      }
    }
  })

  await node.start()
  return node
}

let node1
;(async () => {
  node1 = await createNode()
  console.log("Self is", node1.peerId.toB58String())
})();

I then set my web app to have only /ip4/127.0.0.1/tcp/10001/ws in the bootstrap list. Though this web app works fine connecting to the public IPs in the libp2p-in-the-browser script, it does not manage to discover the bounce.js peer. (“/ip4/127.0.0.1/tcp/10001” also did not work). Probing I find port 10001 is open on localhost, so the problem does not seem to be at the bounce.js end. Am I missing something?

A couple related questions about webrtc-star…

  1. Reading the js-libp2p-webrtc-star README it’s not so obvious how to set oneself up as a WStar listener. They give the example of creating a WStar object manually with WStar({ wrtc: require('wrtc') }), but how do I feed that into Libp2p.create? Can I get Libp2p.create to create the WStar object for me given the wrtc object?

  2. In webrtc-star , if a direct connect fails, particularly due to NAT traversal or firewalls, WebRTC ICE uses a relay TURN server. In other words, ICE will first use STUN with UDP to directly connect peers and, if that fails, will fall back to a TURN relay server.

    Okay. So would it be correct to say that (for my ‘application’ p2p network) the utility of hosting a webrtc “bootstrap” node on the public internet (assuming I already have the websocket “bootstrap” node working) would be only to allow nodes that can connect via webrtc-star but not websockets to enter the network? Webrtc-star peers do not help with initiating connections to other webrtc-star peers (except by gossiping about their existence)? (If this is correct it differs from the impression the comment in the libp2p-in-the-browser example initially gave me.)

    Are nodes able to discover websocket nodes through webrtc-star peers and vice versa? That is, do nodes gossip about the multiaddrs of peers with different connection types?

As a piece of feedback— if every libp2p app effectively has to host its own bootstrap server, that does seem to reduce the usefulness of libp2p. Once I have gone to the bother of setting up a host to run the bootstrap node, for many applications it would have been about as simple to just set up a traditional server for hosting the data. (Setting up a traditional server might even be easier because it could potentially be done inside application hosts such as Apache.) On the other hand, if it were somehow possible for participants in an app to find each other through public gateways such as the bootstrap.libp2p․io servers, this would make libp2p much more useful. Is this something that the “rendezvous” spec (referenced in the issue 744 you link) could possibly help with? A related question— if I understand everything correctly, the bootstrap.libp2p․io and wrtc-star1…dwebops.pub nodes listed in the libp2p-in-the-browser examples could never be used as the basis of any app, because the only thing those nodes can definitely do is gossip about other peers to discover— it seems that there’s no guarantee that any node in that bootstrap list (or among the peers you discover from the bootstrap nodes) will ever support any specific “protocol”, not even the libp2p “official” protocols like kad-dht. What exactly is the purpose of hosting those bootstrap.libp2p․io peers, then? Do they exist only for the sample-code apps like libp2p-in-the-browser to work? Have I missed something?

Thanks for your patience with my many questions.