Missing Resolver instantiation in node:stream docs #60455
Description
Affected URL(s)
Description of the problem
Running the below code yields the error ReferenceError: resolver is not defined.
import { Readable } from 'node:stream';
import { Resolver } from 'node:dns/promises';
await Readable.from([1, 2, 3, 4]).toArray(); // [1, 2, 3, 4]
// Make dns queries concurrently using .map and collect
// the results into an array using toArray
const dnsResults = await Readable.from([
'nodejs.org',
'openjsf.org',
'www.linuxfoundation.org',
]).map(async (domain) => {
const { address } = await resolver.resolve4(domain, { ttl: true });
return address;
}, { concurrency: 2 }).toArray();I suggest instantiating the Resolver object first. For example:
import { Readable } from 'node:stream';
import { Resolver } from 'node:dns/promises';
await Readable.from([1, 2, 3, 4]).toArray(); // [1, 2, 3, 4]
// added line
const resolver = new Resolver();
// Make dns queries concurrently using .map and collect
// the results into an array using toArray
const dnsResults = await Readable.from([
'nodejs.org',
'openjsf.org',
'www.linuxfoundation.org',
]).map(async (domain) => {
const { address } = await resolver.resolve4(domain, { ttl: true });
return address;
}, { concurrency: 2 }).toArray();