libp2p-gossipsub

js-libp2p-gossipsub

Lead Maintainer

Cayman Nava

Table of Contents

• Specs
• Install
• Usage
• API
• Contribute
• License

Specs

Gossipsub is an implementation of pubsub based on meshsub and floodsub. You can read the specification here.

libp2p-gossipsub currently implements the v1.0 of the spec.

Install

npm install libp2p-gossipsub

Usage

const Gossipsub = require('libp2p-gossipsub')

const registrar = {
  handle: (multicodecs, handle) => {
    // register multicodec to libp2p
    // handle function is called everytime a remote peer opens a stream to the peer.
  },
  register: (multicodecs, handlers) => {
    // handlers will be used to notify pubsub of peer connection establishment or closing
  },
  unregister: (id) => {

  }
}

const gsub = new Gossipsub(peerId, registrar, options)

await gsub.start()

gsub.on('fruit', (data) => {
  console.log(data)
})
gsub.subscribe('fruit')

gsub.publish('fruit', new Buffer('banana'))

API

Create a gossipsub implementation

const options = {…}
const gossipsub = new Gossipsub(peerId, registrar, options)

Options is an optional object with the following key-value pairs:

• fallbackToFloodsub: boolean identifying whether the node should fallback to the floodsub protocol, if another connecting peer does not support gossipsub (defaults to true).
• emitSelf: boolean identifying whether the node should emit to self on publish, in the event of the topic being subscribed (defaults to false).
• msgIdFn: a function with signature (message) => string defining the message id given a message, used internally to deduplicate gossip (defaults to (message) => message.from + message.seqno.toString('hex'))
• messageCache: optional, a customized MessageCache instance, see the implementation for the interface.

For the remaining API, see https://github.com/libp2p/js-libp2p-pubsub

Contribute

This module is actively under development. Please check out the issues and submit PRs!

License

MIT © ChainSafe Systems

Changelog

0.4.1 (2020-05-27)

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