@libp2p/kad-dht

JavaScript implementation of the Kad-DHT for libp2p

About

This module implements the libp2p Kademlia spec in TypeScript.

The Kademlia DHT allow for several operations such as finding peers, searching for providers of DHT records, etc.

Example - Using with libp2p

import { kadDHT } from '@libp2p/kad-dht'
import { createLibp2p } from 'libp2p'
import { peerIdFromString } from '@libp2p/peer-id'
import { ping } from '@libp2p/ping'
import { identify } from '@libp2p/identify'

const node = await createLibp2p({
  services: {
    dht: kadDHT({
      // DHT options
    }),
    ping: ping(),
    identify: identify()
  }
})

const peerId = peerIdFromString('QmFoo')
const peerInfo = await node.peerRouting.findPeer(peerId)

console.info(peerInfo) // peer id, multiaddrs
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Example - Connecting to the IPFS Amino DHT

The Amino DHT is a public-good DHT used by IPFS to fetch content, find peers, etc.

If you are trying to access content on the public internet, this is the implementation you want.

import { kadDHT, removePrivateAddressesMapper } from '@libp2p/kad-dht'
import { createLibp2p } from 'libp2p'
import { peerIdFromString } from '@libp2p/peer-id'
import { ping } from '@libp2p/ping'
import { identify } from '@libp2p/identify'

const node = await createLibp2p({
  services: {
    aminoDHT: kadDHT({
      protocol: '/ipfs/kad/1.0.0',
      peerInfoMapper: removePrivateAddressesMapper
    }),
    ping: ping(),
    identify: identify()
  }
})

const peerId = peerIdFromString('QmFoo')
const peerInfo = await node.peerRouting.findPeer(peerId)

console.info(peerInfo) // peer id, multiaddrs
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Example - Connecting to a LAN-only DHT

This DHT only works with privately dialable peers.

This is for use when peers are on the local area network.

import { kadDHT, removePublicAddressesMapper } from '@libp2p/kad-dht'
import { createLibp2p } from 'libp2p'
import { peerIdFromString } from '@libp2p/peer-id'
import { ping } from '@libp2p/ping'
import { identify } from '@libp2p/identify'

const node = await createLibp2p({
  services: {
    lanDHT: kadDHT({
      protocol: '/ipfs/lan/kad/1.0.0',
      peerInfoMapper: removePublicAddressesMapper,
      clientMode: false
    }),
    ping: ping(),
    identify: identify()
  }
})

const peerId = peerIdFromString('QmFoo')
const peerInfo = await node.peerRouting.findPeer(peerId)

console.info(peerInfo) // peer id, multiaddrs
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Example - Connecting to both a LAN-only DHT and the IPFS Amino DHT

When using multiple DHTs, you should specify distinct datastore, metrics and log prefixes to ensure that data is kept separate for each instance.

import { kadDHT, removePublicAddressesMapper, removePrivateAddressesMapper } from '@libp2p/kad-dht'
import { createLibp2p } from 'libp2p'
import { peerIdFromString } from '@libp2p/peer-id'
import { ping } from '@libp2p/ping'
import { identify } from '@libp2p/identify'

const node = await createLibp2p({
  services: {
    lanDHT: kadDHT({
      protocol: '/ipfs/lan/kad/1.0.0',
      peerInfoMapper: removePublicAddressesMapper,
      clientMode: false,
      logPrefix: 'libp2p:dht-lan',
      datastorePrefix: '/dht-lan',
      metricsPrefix: 'libp2p_dht_lan'
    }),
    aminoDHT: kadDHT({
      protocol: '/ipfs/kad/1.0.0',
      peerInfoMapper: removePrivateAddressesMapper,
      logPrefix: 'libp2p:dht-amino',
      datastorePrefix: '/dht-amino',
      metricsPrefix: 'libp2p_dht_amino'
    }),
    ping: ping(),
    identify: identify()
  }
})

const peerId = peerIdFromString('QmFoo')
const peerInfo = await node.peerRouting.findPeer(peerId)

console.info(peerInfo) // peer id, multiaddrs
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Install

$ npm i @libp2p/kad-dht
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Browser <script> tag

Loading this module through a script tag will make its exports available as Libp2pKadDht in the global namespace.

<script src="https://unpkg.com/@libp2p/kad-dht/dist/index.min.js"></script>
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API Docs

• https://libp2p.github.io/js-libp2p/modules/_libp2p_kad_dht.html

License

Licensed under either of

• Apache 2.0, (LICENSE-APACHE / http://www.apache.org/licenses/LICENSE-2.0)
• MIT (LICENSE-MIT / http://opensource.org/licenses/MIT)

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.