libp2p-websocket-star

libp2p-webrtc-star without webrtc. Just plain socket.io.

Description

libp2p-websocket-star is one of the Websocket transports available for libp2p. libp2p-websocket-star incorporates both a transport and a discovery service that is facilitated by the signalling server, also part of this module.

Note: This module uses pull-streams for all stream based interfaces.

Usage

Installation

> npm install libp2p-websocket-star

API

Example

const libp2p = require("libp2p")
const Id = require("peer-id")
const Info = require("peer-info")
const multiaddr = require("multiaddr")
const pull = require('pull-stream')

const WSStar = require('libp2p-websocket-star')

Id.create((err, id) => {
  if (err) throw err

  const peerInfo = new Info(id)
  peerInfo.multiaddrs.add(multiaddr("/dns4/ws-star-signal-1.servep2p.com/wss/p2p-websocket-star/"))
  const ws = new WSStar({ id }) //the id is required for the crypto challenge
  const modules = {
    transport: [
      ws
    ],
    discovery: [
      ws.discovery
    ]
  }
  const swarm = new libp2p(modules, peerInfo)

  swarm.handle("/test/1.0.0", (protocol, conn) => {
    pull(
      pull.values(['hello']),
      conn,
      pull.map(s => s.toString()),
      pull.log()
    )
  })

  swarm.start(err => {
    if (err) throw err
    swarm.dial(peerInfo, "/test/1.0.0", (err, conn) => {
      if (err) throw err
      pull(
        pull.values(['hello from the other side']),
        conn,
        pull.map(s => s.toString()),
        pull.log()
      )
    })
  })
})

Outputs:

hello
hello from the other side

Signalling server

libp2p-websocket-star comes with its own signalling server, used for peers to handshake their signalling data and establish a connection. You can install it in your machine by installing the module globally:

> npm install --global libp2p-websocket-star-signal

This will expose a ws-star-sig cli tool. To spawn a server do:

> ws-star-signal --port=9090 --host=127.0.0.1

Defaults:

• port - 13579
• host - '0.0.0.0'

Hosted Signalling Server

We host a signalling server at ws-star-signal-1.servep2p.com and ws-star-signal-2.servep2p.com that can be used for practical demos and experimentation, it should not be used for apps in production. A libp2p-websocket-star address, using the signalling server we provide, looks like:

/dns4/ws-star-signal-1.servep2p.com/wss/p2p-websocket-star/ipfs/<your-peer-id>

Note: The address above indicates WebSockets Secure, which can be accessed from both http and https.

This module uses pull-streams

We expose a streaming interface based on pull-streams, rather then on the Node.js core streams implementation (aka Node.js streams). pull-streams offers us a better mechanism for error handling and flow control guarantees. If you would like to know more about why we did this, see the discussion at this issue.

You can learn more about pull-streams at:

• The history of Node.js streams, nodebp April 2014
• The history of streams, 2016
• pull-streams, the simple streaming primitive
• pull-streams documentation

Converting pull-streams to Node.js Streams

If you are a Node.js streams user, you can convert a pull-stream to a Node.js stream using the module pull-stream-to-stream, giving you an instance of a Node.js stream that is linked to the pull-stream. For example:

const pullToStream = require('pull-stream-to-stream')

const nodeStreamInstance = pullToStream(pullStreamInstance)
// nodeStreamInstance is an instance of a Node.js Stream

To learn more about this utility, visit https://pull-stream.github.io/#pull-stream-to-stream.