Update exports in index.ts to include .js extensions, add centralized WHOIS server fallbacks for TLDs in whois-fallbacks.ts, and integrate fallbacks into the ianaWhoisServerForTld function in whois.ts for improved error handling.

src/index.ts

@@ -1,2 +1,2 @@
-export * from "./lookup";
+export * from "./lookup.js";
-export * from "./types";
+// export * from "./types.js";

src/whois-fallbacks.ts

@@ -0,0 +1,84 @@
+// Centralized WHOIS server fallbacks by TLD.
+// These are used when IANA's TLD page does not list a server or is unreachable.
+export const WHOIS_FALLBACKS: Record<string, string> = {
+  // gTLDs
+  com: "whois.verisign-grs.com",
+  net: "whois.verisign-grs.com",
+  org: "whois.pir.org",
+  info: "whois.afilias.net",
+  biz: "whois.nic.biz",
+  xyz: "whois.nic.xyz",
+  top: "whois.nic.top",
+  club: "whois.nic.club",
+  site: "whois.nic.site",
+  online: "whois.nic.online",
+  shop: "whois.nic.shop",
+  store: "whois.nic.store",
+  tech: "whois.nic.tech",
+  space: "whois.nic.space",
+  link: "whois.nic.link",
+  guru: "whois.nic.guru",
+  mobi: "whois.nic.mobi",
+  name: "whois.nic.name",
+  pro: "whois.nic.pro",
+  tel: "whois.nic.tel",
+  travel: "whois.nic.travel",
+  aero: "whois.aero",
+  jobs: "whois.nic.jobs",
+  cat: "whois.nic.cat",
+  museum: "whois.museum",
+  coop: "whois.nic.coop",
+  asia: "whois.nic.asia",
+  app: "whois.nic.google",
+  dev: "whois.nic.google",
+  page: "whois.nic.google",
+  blog: "whois.nic.blog",
+  // ccTLDs (port 43 policy varies by registry)
+  us: "whois.nic.us",
+  uk: "whois.nic.uk",
+  co: "whois.nic.co",
+  me: "whois.nic.me",
+  tv: "whois.nic.tv",
+  io: "whois.nic.io",
+  ai: "whois.nic.ai",
+  de: "whois.denic.de",
+  fr: "whois.nic.fr",
+  nl: "whois.domain-registry.nl",
+  ru: "whois.tcinet.ru",
+  pl: "whois.dns.pl",
+  br: "whois.registro.br",
+  it: "whois.nic.it",
+  es: "whois.nic.es",
+  se: "whois.iis.se",
+  no: "whois.norid.no",
+  dk: "whois.dk-hostmaster.dk",
+  fi: "whois.fi",
+  ch: "whois.nic.ch",
+  at: "whois.nic.at",
+  be: "whois.dns.be",
+  cz: "whois.nic.cz",
+  sk: "whois.sk-nic.sk",
+  hu: "whois.nic.hu",
+  ro: "whois.rotld.ro",
+  bg: "whois.register.bg",
+  gr: "whois.ics.forth.gr",
+  tr: "whois.trabis.gov.tr",
+  il: "whois.isoc.org.il",
+  za: "whois.registry.net.za",
+  nz: "whois.srs.net.nz",
+  jp: "whois.jprs.jp",
+  cn: "whois.cnnic.cn",
+  kr: "whois.kr",
+  tw: "whois.twnic.net.tw",
+  sg: "whois.sgnic.sg",
+  hk: "whois.hkirc.hk",
+  id: "whois.id",
+  my: "whois.mynic.my",
+  ph: "whois.dot.ph",
+  th: "whois.thnic.co.th",
+  vn: "whois.vnnic.vn",
+  mx: "whois.mx",
+  ar: "whois.nic.ar",
+  cl: "whois.nic.cl",
+  pe: "kero.yachay.pe",
+};

src/whois.ts

@@ -2,6 +2,7 @@ import { createConnection } from "node:net";
 import { DEFAULT_TIMEOUT_MS } from "./config.js";
 import type { LookupOptions } from "./types.js";
 import { withTimeout } from "./utils.js";
+import { WHOIS_FALLBACKS } from "./whois-fallbacks.js";
 
 export interface WhoisQueryResult {
   serverQueried: string;
@@ -84,10 +85,15 @@ export async function ianaWhoisServerForTld(
       html.match(/Whois Server:\s*<a[^>]*>([^<]+)<\/a>/i) ||
       html.match(/Whois Server:\s*([^<\n]+)/i);
     const server = m?.[1]?.trim();
-    if (!server) return undefined;
+    if (!server)
+      return (
+        WHOIS_FALLBACKS[tld.toLowerCase()] ?? `whois.nic.${tld.toLowerCase()}`
+      );
     return server.replace(/^https?:\/\//i, "").replace(/\/$/, "");
   } catch {
-    return undefined;
+    return (
+      WHOIS_FALLBACKS[tld.toLowerCase()] ?? `whois.nic.${tld.toLowerCase()}`
+    );
   }
 }