import { lookup } from 'dns' import { parse as parseIP } from 'ipaddr.js' function dnsLookupAll (hostname: string) { return new Promise((res, rej) => { lookup(hostname, { family: 0, all: true }, (err, adresses) => { if (err) return rej(err) return res(adresses.map(a => a.address)) }) }) } async function isResolvingToUnicastOnly (hostname: string) { const addresses = await dnsLookupAll(hostname) for (const address of addresses) { const parsed = parseIP(address) if (parsed.range() !== 'unicast') return false } return true } export { dnsLookupAll, isResolvingToUnicastOnly }