libp2p-mdns

libp2p-mdns JavaScript implementation
=====================================


> JavaScript libp2p MulticastDNS discovery implementation

Lead Maintainer

Jacob Heun

Usage

``JavaScript
const MDNS = require('libp2p-mdns')

const mdns = new MDNS(options)

mdns.on('peer', (peerData) => {
console.log('Found a peer in the local network', peerData.id.toB58String(), peerData.multiaddrs)
})

// Broadcast for 20 seconds
mdns.start()
setTimeout(() => mdns.stop(), 20 * 1000)
`

- options
- peerId - PeerId to announce
- multiaddrs - multiaddrs to announce
- broadcast - (true/false) announce our presence through mDNS, default false
- interval - query interval, default 10 * 1000 (10 seconds)
- serviceTag - name of the service announce , default 'ipfs.local
- compat - enable/disable compatibility with go-libp2p-mdns, default true

MDNS messages

A query is sent to discover the IPFS nodes on the local network

``
{ type: 'query',
questions: [ { name: 'ipfs.local', type: 'PTR' } ]
}
`

When a query is detected, each IPFS node sends an answer about itself

`
[ { name: 'ipfs.local',
type: 'PTR',
class: 'IN',
ttl: 120,
data: 'QmNPubsDWATVngE3d5WDSNe7eVrFLuk38qb9t6vdLnu2aK.ipfs.local' },
{ name: 'QmNPubsDWATVngE3d5WDSNe7eVrFLuk38qb9t6vdLnu2aK.ipfs.local',
type: 'SRV',
class: 'IN',
ttl: 120,
data:
{ priority: 10,
weight: 1,
port: '20002',
target: 'LAPTOP-G5LJ7VN9' } },
{ name: 'QmNPubsDWATVngE3d5WDSNe7eVrFLuk38qb9t6vdLnu2aK.ipfs.local',
type: 'TXT',
class: 'IN',
ttl: 120,
data: ['QmNPubsDWATVngE3d5WDSNe7eVrFLuk38qb9t6vdLnu2aK'] },
{ name: 'LAPTOP-G5LJ7VN9',
type: 'A',
class: 'IN',
ttl: 120,
data: '127.0.0.1' },
{ name: 'LAPTOP-G5LJ7VN9',
type: 'AAAA',
class: 'IN',
ttl: 120,
data: '::1' } ]
``