Node.JS module for getting ASN for a given IP address. It uses data from http://thyme.apnic.net/current/ .
Mostly inspired by https://www.npmjs.com/package/iptoasn but without native code and using async/await instead of callback style.
npm install --save asnlookup
This module downloads raw BGP table (~13MB) and ASN to name mapping (~2MB) files from http://thyme.apnic.net/current/ and converts them into a more useful format that allows for a quick search.
WARNING: To improve the lookup speed by a lot only /16 at most is currently supported as the first 2 bytes of the address is used for quick lookup! On the upside this makes it more specific for ranges covered by various ASNs
'use strict'; // you must pass a filepath for the local cache, otherwise .asnlookup.cache will be used const asnlookup = require('./index.js')('.asnlookup.cache'); (async function() { const testArray = [ '8.8.8.8', '50.22.180.100', '1.2.3.4', '104.16.181.15', '127.0.0.1', 'asd' ]; // call .load() for an attempt to load the local cache, this will require 10s of MB of memory! await asnlookup.load(); // check when the cache was updated // lastUpdated are days // lastUpdated is Infinity if there's no cache at all const lastUpdated = asnlookup.lastUpdated(); console.log(`Last updated ${lastUpdated} days ago.`); // update the cache if it's older than 31 days if (lastUpdated > 31) { console.log('Cache too old or never created. Updating...'); await asnlookup.update(); } testArray.forEach(function(ip) { console.log(ip, '-', asnlookup.lookup(ip)); }); })();Result of this sample script:
Last updated 0 days ago. 8.8.8.8 - LEVEL3 50.22.180.100 - SOFTLAYER 1.2.3.4 - null 104.16.181.15 - CLOUDFLARENET 127.0.0.1 - null asd - null