dns: expose getDefaultResultOrder

PR-URL: https://github.com/nodejs/node/pull/46973
Fixes: https://github.com/nodejs/node/issues/46919
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Paolo Insogna <paolo@cowtech.it>

doc/api/dns.md

@@ -792,6 +792,18 @@ priority than [`--dns-result-order`][]. When using [worker threads][],
 [`dns.setDefaultResultOrder()`][] from the main thread won't affect the default
 dns orders in workers.
 
+## `dns.getDefaultResultOrder()`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+Get the default value for `verbatim` in [`dns.lookup()`][] and
+[`dnsPromises.lookup()`][]. The value could be:
+
+* `ipv4first`: for `verbatim` defaulting to `false`.
+* `verbatim`: for `verbatim` defaulting to `true`.
+
 ## `dns.setServers(servers)`
 
 <!-- YAML
@@ -1351,6 +1363,14 @@ higher priority than [`--dns-result-order`][]. When using [worker threads][],
 [`dnsPromises.setDefaultResultOrder()`][] from the main thread won't affect the
 default dns orders in workers.
 
+### `dnsPromises.getDefaultResultOrder()`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+Get the value of `dnsOrder`.
+
 ### `dnsPromises.setServers(servers)`
 
 <!-- YAML

lib/dns.js

@@ -38,6 +38,7 @@ const {
   validateHints,
   emitInvalidHostnameWarning,
   getDefaultVerbatim,
+  getDefaultResultOrder,
   setDefaultResultOrder,
   errorCodes: dnsErrorCodes,
 } = require('internal/dns/utils');
@@ -305,6 +306,7 @@ module.exports = {
   lookupService,
 
   Resolver,
+  getDefaultResultOrder,
   setDefaultResultOrder,
   setServers: defaultResolverSetServers,
 

lib/internal/dns/promises.js

@@ -14,6 +14,7 @@ const {
   emitInvalidHostnameWarning,
   getDefaultVerbatim,
   errorCodes: dnsErrorCodes,
+  getDefaultResultOrder,
   setDefaultResultOrder,
   setDefaultResolver,
 } = require('internal/dns/utils');
@@ -335,6 +336,7 @@ module.exports = {
   lookup,
   lookupService,
   Resolver,
+  getDefaultResultOrder,
   setDefaultResultOrder,
   setServers: defaultResolverSetServers,
 

lib/internal/dns/utils.js

@@ -284,6 +284,10 @@ function setDefaultResultOrder(value) {
   dnsOrder = value;
 }
 
+function getDefaultResultOrder() {
+  return dnsOrder;
+}
+
 function createResolverClass(resolver) {
   const resolveMap = { __proto__: null };
 
@@ -346,6 +350,7 @@ module.exports = {
   validateTries,
   emitInvalidHostnameWarning,
   getDefaultVerbatim,
+  getDefaultResultOrder,
   setDefaultResultOrder,
   errorCodes,
   createResolverClass,

test/internet/test-dns-getDefaultResultOrder.js

@@ -0,0 +1,24 @@
+'use strict';
+
+const common = require('../common');
+
+const assert = require('assert');
+const dns = require('dns');
+
+dns.setDefaultResultOrder('ipv4first');
+let dnsOrder = dns.getDefaultResultOrder();
+assert.ok(dnsOrder === 'ipv4first');
+dns.setDefaultResultOrder('verbatim');
+dnsOrder = dns.getDefaultResultOrder();
+assert.ok(dnsOrder === 'verbatim');
+
+{
+  (async function() {
+    const result = await dns.promises.lookup('localhost');
+    const result1 = await dns.promises.lookup('localhost', { verbatim: true });
+    assert.ok(result !== undefined);
+    assert.ok(result1 !== undefined);
+    assert.ok(result.address === result1.address);
+    assert.ok(result.family === result1.family);
+  })().then(common.mustCall());
+}