@helia/ipns

An implementation of IPNS for Helia

About

IPNS operations using a Helia node

Example - Getting started

With IPNSRouting routers:

import { createHelia } from 'helia'
import { ipns } from '@helia/ipns'
import { unixfs } from '@helia/unixfs'

const helia = await createHelia()
const name = ipns(helia)

// create a public key to publish as an IPNS name
const keyInfo = await helia.libp2p.services.keychain.createKey('my-key')
const peerId = await helia.libp2p.services.keychain.exportPeerId(keyInfo.name)

// store some data to publish
const fs = unixfs(helia)
const cid = await fs.add(Uint8Array.from([0, 1, 2, 3, 4]))

// publish the name
await name.publish(peerId, cid)

// resolve the name
const result = name.resolve(peerId)

console.info(result.cid, result.path)
Copy

Example - Publishing a recursive record

A recursive record is a one that points to another record rather than to a value.

import { createHelia } from 'helia'
import { ipns } from '@helia/ipns'
import { unixfs } from '@helia/unixfs'

const helia = await createHelia()
const name = ipns(helia)

// create a public key to publish as an IPNS name
const keyInfo = await helia.libp2p.services.keychain.createKey('my-key')
const peerId = await helia.libp2p.services.keychain.exportPeerId(keyInfo.name)

// store some data to publish
const fs = unixfs(helia)
const cid = await fs.add(Uint8Array.from([0, 1, 2, 3, 4]))

// publish the name
await name.publish(peerId, cid)

// create another public key to re-publish the original record
const recursiveKeyInfo = await helia.libp2p.services.keychain.createKey('my-recursive-key')
const recursivePeerId = await helia.libp2p.services.keychain.exportPeerId(recursiveKeyInfo.name)

// publish the recursive name
await name.publish(recursivePeerId, peerId)

// resolve the name recursively - it resolves until a CID is found
const result = name.resolve(recursivePeerId)
console.info(result.cid.toString() === cid.toString()) // true
Copy

Example - Publishing a record with a path

It is possible to publish CIDs with an associated path.

import { createHelia } from 'helia'
import { ipns } from '@helia/ipns'
import { unixfs } from '@helia/unixfs'

const helia = await createHelia()
const name = ipns(helia)

// create a public key to publish as an IPNS name
const keyInfo = await helia.libp2p.services.keychain.createKey('my-key')
const peerId = await helia.libp2p.services.keychain.exportPeerId(keyInfo.name)

// store some data to publish
const fs = unixfs(helia)
const fileCid = await fs.add(Uint8Array.from([0, 1, 2, 3, 4]))

// store the file in a directory
const dirCid = await fs.mkdir()
const finalDirCid = await fs.cp(fileCid, dirCid, '/foo.txt')

// publish the name
await name.publish(peerId, `/ipfs/${finalDirCid}/foo.txt)

// resolve the name
const result = name.resolve(peerId)

console.info(result.cid, result.path) // QmFoo.. 'foo.txt'
Copy

Example - Using custom PubSub router

Additional IPNS routers can be configured - these enable alternative means to publish and resolve IPNS names.

One example is the PubSub router - this requires an instance of Helia with libp2p PubSub configured.

It works by subscribing to a pubsub topic for each IPNS name that we try to resolve. Updated IPNS records are shared on these topics so an update must occur before the name is resolvable.

This router is only suitable for networks where IPNS updates are frequent and multiple peers are listening on the topic(s), otherwise update messages may fail to be published with "Insufficient peers" errors.

import { createHelia, libp2pDefaults } from 'helia'
import { ipns } from '@helia/ipns'
import { pubsub } from '@helia/ipns/routing'
import { unixfs } from '@helia/unixfs'
import { gossipsub } from '@chainsafe/libp2p-gossipsub'

const libp2pOptions = libp2pDefaults()
libp2pOptions.services.pubsub = gossipsub()

const helia = await createHelia({
  libp2p: libp2pOptions
})
const name = ipns(helia, {
 routers: [
   pubsub(helia)
 ]
})

// create a public key to publish as an IPNS name
const keyInfo = await helia.libp2p.services.keychain.createKey('my-key')
const peerId = await helia.libp2p.services.keychain.exportPeerId(keyInfo.name)

// store some data to publish
const fs = unixfs(helia)
const cid = await fs.add(Uint8Array.from([0, 1, 2, 3, 4]))

// publish the name
await name.publish(peerId, cid)

// resolve the name
const { cid, path } = name.resolve(peerId)
Copy

Example - Using custom DNS over HTTPS resolvers

With default DNSResolver resolvers:

import { createHelia } from 'helia'
import { ipns } from '@helia/ipns'
import { unixfs } from '@helia/unixfs'
import { dnsOverHttps } from '@helia/ipns/dns-resolvers'

const helia = await createHelia()
const name = ipns(helia, {
 resolvers: [
   dnsOverHttps('https://private-dns-server.me/dns-query'),
 ]
})

const { cid, path } = name.resolveDns('some-domain-with-dnslink-entry.com')
Copy

Example - Resolving a domain with a dnslink entry

Calling resolveDns with the @helia/ipns instance:

// resolve a CID from a TXT record in a DNS zone file, using the default
// resolver for the current platform eg:
// > dig _dnslink.ipfs.io TXT
// ;; ANSWER SECTION:
// _dnslink.ipfs.io.          60     IN      TXT     "dnslink=/ipns/website.ipfs.io"
// > dig _dnslink.website.ipfs.io TXT
// ;; ANSWER SECTION:
// _dnslink.website.ipfs.io.  60     IN      TXT     "dnslink=/ipfs/QmWebsite"

const { cid, path } = name.resolveDns('ipfs.io')

console.info(cid)
// QmWebsite
Copy

Example - Using DNS-Over-HTTPS

This example uses the Mozilla provided RFC 1035 DNS over HTTPS service. This uses binary DNS records so requires extra dependencies to process the response which can increase browser bundle sizes.

If this is a concern, use the DNS-JSON-Over-HTTPS resolver instead.

// use DNS-Over-HTTPS
import { dnsOverHttps } from '@helia/ipns/dns-resolvers'

const { cid, path } = name.resolveDns('ipfs.io', {
  resolvers: [
    dnsOverHttps('https://mozilla.cloudflare-dns.com/dns-query')
  ]
})
Copy

Example - Using DNS-JSON-Over-HTTPS

DNS-JSON-Over-HTTPS resolvers use the RFC 8427 application/dns-json and can result in a smaller browser bundle due to the response being plain JSON.

// use DNS-JSON-Over-HTTPS
import { dnsJsonOverHttps } from '@helia/ipns/dns-resolvers'

const { cid, path } = name.resolveDns('ipfs.io', {
  resolvers: [
    dnsJsonOverHttps('https://mozilla.cloudflare-dns.com/dns-query')
  ]
})
Copy

Install

$ npm i @helia/ipns
Copy

Browser <script> tag

Loading this module through a script tag will make it's exports available as HeliaIpns in the global namespace.

<script src="https://unpkg.com/@helia/ipns/dist/index.min.js"></script>
Copy

API Docs

• https://ipfs.github.io/helia/modules/_helia_ipns.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)

Contribute

Contributions welcome! Please check out the issues.

Also see our contributing document for more information on how we work, and about contributing in general.

Please be aware that all interactions related to this repo are subject to the IPFS Code of Conduct.

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.