Why

BIMI is the standard behind the brand logo mailbox providers show next to an email. Domains publish it as a TXT record:

$ dig +short TXT default._bimi.microlink.io
"v=BIMI1; l=https://cdn.microlink.io/logo/logo.svg;"

The specification constrains the logo to SVG Tiny P/S: vector, square, and transparent, which is exactly the shape a logo is expected to have.

The record is published in the domain's own DNS, so it is self asserted: the same level of trust as og:logo. Domains may also publish a Verified Mark Certificate under a=, where a certificate authority has attested the mark against the trademark owner, but this package does not read or validate it.

That makes it a higher quality source than a favicon, and it doesn't need the markup: a single DNS lookup, so it works even when the page is JavaScript rendered or unreachable.

Coverage is the trade-off. It's common among large brands and rare in the long tail, so pair it with metascraper-logo and metascraper-logo-favicon.

Install

$ npm install metascraper-logo-bimi --save

Usage

Rules are evaluated in the order the packages are declared, so put it first to prefer the BIMI published logo over anything found in the markup:

const metascraper = require('metascraper')([
  require('metascraper-logo-bimi')(),
  require('metascraper-logo')(),
  require('metascraper-logo-favicon')()
])

The lookup is done against the registrable domain, meaning https://blog.example.com/post resolves default._bimi.example.com.

API

metascraper-logo-bimi([options])

The record is read by bimi-url, and every option is passed to it: gotOpts, keyvOpts, resolveLogoUrl, resolveTxt, and selector are documented there.

Supplying your own resolveTxt is the common one, since node:dns resolves with no timeout by default:

const { Resolver } = require('dns').promises

const resolver = new Resolver({ timeout: 2000 })

const metascraper = require('metascraper')([
  require('metascraper-logo-bimi')({
    resolveTxt: hostname => resolver.resolveTxt(hostname)
  })
])

The same seam takes a DNS over HTTPS resolver, so the lookup leaves through the same egress as the rest of your traffic. bimi-url has that example.

createGetLogo, resolveLogoUrl and toLogoUrl are re-exported from bimi-url for use outside a metascraper rule.

License

metascraper-logo-bimi © Microlink, released under the MIT License. Authored and maintained by Microlink with help from contributors.

microlink.io · GitHub microlinkhq · X @microlinkhq