Module index

Example: Getting started

With IPNSRouting routers:

import { createHelia } from 'helia'
import { ipns } from '@helia/ipns'
import { unixfs } from '@helia/unixfs'
import { generateKeyPair } from '@libp2p/crypto/keys'

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

// create a keypair to publish an IPNS name
const privateKey = await generateKeyPair('Ed25519')

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

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

// resolve the name
const result = await name.resolve(privateKey.publicKey)

console.info(result.cid, result.path)
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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'
import { generateKeyPair } from '@libp2p/crypto/keys'

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

// create a keypair to publish an IPNS name
const privateKey = await generateKeyPair('Ed25519')

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

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

// create another keypair to re-publish the original record
const recursivePrivateKey = await generateKeyPair('Ed25519')

// publish the recursive name
await name.publish(recursivePrivateKey, privateKey.publicKey)

// resolve the name recursively - it resolves until a CID is found
const result = await name.resolve(recursivePrivateKey.publicKey)
console.info(result.cid.toString() === cid.toString()) // true
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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'
import { generateKeyPair } from '@libp2p/crypto/keys'

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

// create a keypair to publish an IPNS name
const privateKey = await generateKeyPair('Ed25519')

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

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

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

// resolve the name
const result = await name.resolve(privateKey.publicKey)

console.info(result.cid, result.path) // QmFoo.. 'foo.txt'
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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'
import { generateKeyPair } from '@libp2p/crypto/keys'
import type { Libp2p, PubSub } from '@libp2p/interface'
import type { DefaultLibp2pServices } from 'helia'

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

const helia = await createHelia<Libp2p<DefaultLibp2pServices & { pubsub: PubSub }>>({
  libp2p: libp2pOptions
})
const name = ipns(helia, {
 routers: [
   pubsub(helia)
 ]
})

// create a keypair to publish an IPNS name
const privateKey = await generateKeyPair('Ed25519')

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

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

// resolve the name
const result = await name.resolve(privateKey.publicKey)
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Example: Using custom DNS over HTTPS resolvers

To use custom resolvers, configure Helia's dns option:

import { createHelia } from 'helia'
import { ipns } from '@helia/ipns'
import { dns } from '@multiformats/dns'
import { dnsOverHttps } from '@multiformats/dns/resolvers'
import { helia } from '@helia/ipns/routing'

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

const result = name.resolveDNSLink('some-domain-with-dnslink-entry.com')
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Example: Resolving a domain with a dnslink entry

Calling resolveDNSLink 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"

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

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

const { answer } = await name.resolveDNSLink('ipfs.io')

console.info(answer)
// { data: '/ipfs/QmWebsite' }
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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.

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

const node = await createHelia({
  dns: dns({
    resolvers: {
      '.': dnsOverHttps('https://mozilla.cloudflare-dns.com/dns-query')
    }
  })
})
const name = ipns(node)

const result = await name.resolveDNSLink('ipfs.io')
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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.

import { createHelia } from 'helia'
import { ipns } from '@helia/ipns'
import { dns } from '@multiformats/dns'
import { dnsJsonOverHttps } from '@multiformats/dns/resolvers'

const node = await createHelia({
  dns: dns({
    resolvers: {
      '.': dnsJsonOverHttps('https://mozilla.cloudflare-dns.com/dns-query')
    }
  })
})
const name = ipns(node)

const result = await name.resolveDNSLink('ipfs.io')
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Example: Republishing an existing IPNS record

The republishRecord method allows you to republish an existing IPNS record without needing the private key. This is useful for relay nodes or when you want to extend the availability of a record that was created elsewhere.

import { createHelia } from 'helia'
import { ipns } from '@helia/ipns'
import { createDelegatedRoutingV1HttpApiClient } from '@helia/delegated-routing-v1-http-api-client'
import { CID } from 'multiformats/cid'

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

const ipnsName = 'k51qzi5uqu5dktsyfv7xz8h631pri4ct7osmb43nibxiojpttxzoft6hdyyzg4'
const parsedCid: CID<unknown, 114, 0 | 18, 1> = CID.parse(ipnsName)
const delegatedClient = createDelegatedRoutingV1HttpApiClient('https://delegated-ipfs.dev')
const record = await delegatedClient.getIPNS(parsedCid)

await name.republishRecord(ipnsName, record)
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