Module @helia/dnslink

Example: Using custom DNS over HTTPS resolvers

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

import { createHelia } from 'helia'
import { dnsLink } from '@helia/dnslink'
import { dns } from '@multiformats/dns'
import { dnsOverHttps } from '@multiformats/dns/resolvers'
import type { DefaultLibp2pServices } from 'helia'
import type { Libp2p } from '@libp2p/interface'

const node = await createHelia<Libp2p<DefaultLibp2pServices>>({
  dns: dns({
    resolvers: {
      '.': dnsOverHttps('https://private-dns-server.me/dns-query')
    }
  })
})
const name = dnsLink(node)

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

Calling resolve with the @helia/dnslink 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.tech TXT
// ;; ANSWER SECTION:
// _dnslink.ipfs.tech. 60 IN CNAME _dnslink.ipfs-tech.on.fleek.co.
// _dnslink.ipfs-tech.on.fleek.co. 120 IN TXT "dnslink=/ipfs/bafybe..."

import { createHelia } from 'helia'
import { dnsLink } from '@helia/dnslink'

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

const [{ answer }] = await name.resolve('blog.ipfs.tech')

console.info(answer)
// { data: '/ipfs/bafybe...' }
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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 { dnsLink } from '@helia/dnslink'
import { dns } from '@multiformats/dns'
import { dnsOverHttps } from '@multiformats/dns/resolvers'
import type { DefaultLibp2pServices } from 'helia'
import type { Libp2p } from '@libp2p/interface'

const node = await createHelia<Libp2p<DefaultLibp2pServices>>({
  dns: dns({
    resolvers: {
      '.': dnsOverHttps('https://mozilla.cloudflare-dns.com/dns-query')
    }
  })
})
const name = dnsLink(node)

const result = await name.resolve('blog.ipfs.tech')
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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 { dnsLink } from '@helia/dnslink'
import { dns } from '@multiformats/dns'
import { dnsJsonOverHttps } from '@multiformats/dns/resolvers'
import type { DefaultLibp2pServices } from 'helia'
import type { Libp2p } from '@libp2p/interface'

const node = await createHelia<Libp2p<DefaultLibp2pServices>>({
  dns: dns({
    resolvers: {
      '.': dnsJsonOverHttps('https://mozilla.cloudflare-dns.com/dns-query')
    }
  })
})
const name = dnsLink(node)

const result = await name.resolve('blog.ipfs.tech')
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