@iocium/favicon-fetcher

A simple TypeScript utility for fetching favicons and BIMI logos from major providers, compatible with Cloudflare Workers, modern browsers, and Node.js.

Install

npm install @iocium/favicon-fetcher

Usage

import { FaviconFetcher } from '@iocium/favicon-fetcher';

const fetcher = new FaviconFetcher('github.com', {
  iconHorseApiKey: 'your-api-key-here'
});
const result = await fetcher.fetchFavicon('iconHorse');

console.log(result.status, result.contentType);

Providers

• Google
• DuckDuckGo
• Bitwarden
• Yandex
• Fastmail
• icon.horse (Pro support via X-API-Key)
• NextDNS
• BIMI (via DNS TXT record lookup)

Configuration

useCorsProxy

Use this option to fetch through a CORS proxy when running in a browser:

new FaviconFetcher('github.com', {
  useCorsProxy: true // uses https://corsproxy.io/?
});

new FaviconFetcher('github.com', {
  useCorsProxy: 'https://my-cors-proxy/'
});

iconHorseApiKey

Use this to authenticate with icon.horse Pro.

new FaviconFetcher('github.com', {
  iconHorseApiKey: 'your-api-key'
});

This will override any X-API-Key passed manually in headers.

headers

Set custom headers for fetch requests. Useful for user-agent tagging or auth with custom endpoints:

new FaviconFetcher('example.com', {
  headers: {
    'User-Agent': 'MyFaviconBot/1.0'
  }
});

Note: X-API-Key will be overridden if using iconHorseApiKey.

dohServerUrl

Override the DNS-over-HTTPS server used for BIMI lookups (default: Cloudflare):

new FaviconFetcher('paypal.com', {
  dohServerUrl: 'https://dns.google/dns-query'
});

Advanced Examples

🔹 Fetching a BIMI logo (SVG)

const fetcher = new FaviconFetcher('paypal.com');
const result = await fetcher.fetchFavicon('bimi');

console.log(result.url);         // BIMI logo URL from TXT record
console.log(result.status);      // 200 if success
console.log(result.contentType); // image/svg+xml
console.log(result.content);     // ArrayBuffer (SVG image)

---

🔹 Using a custom DoH server for BIMI

By default, BIMI lookups use Cloudflare's DoH endpoint, but you can override this if you prefer another provider like Google or NextDNS:

const fetcher = new FaviconFetcher('paypal.com', {
  dohServerUrl: 'https://dns.google/dns-query'
});
const result = await fetcher.fetchFavicon('bimi');

Supported DoH endpoints:

• Cloudflare: https://cloudflare-dns.com/dns-query (default)
• Google: https://dns.google/dns-query
• NextDNS: https://dns.nextdns.io/YOUR_PROFILE_ID

⚠️ Ensure the DoH server supports application/dns-json responses (RFC 8484 JSON mode). No validation is performed on this URL — garbage in, garbage out.

---

🔹 Combining options: icon.horse Pro, custom headers, and CORS proxy

const fetcher = new FaviconFetcher('github.com', {
  iconHorseApiKey: 'your-real-api-key',
  useCorsProxy: 'https://my-cors-proxy/',
  headers: {
    'User-Agent': 'FaviconFetcherBot/2.0'
  }
});
const result = await fetcher.fetchFavicon('iconHorse');

Testing

npm test         # Runs mocked tests
npm run test:live  # Runs real network integration tests (LIVE_TEST=true)

License

MIT