Instances of the worker.MessageChannel class represent an asynchronous, two-way communications channel. The MessageChannel has no methods of its own. new MessageChannel()yields an object with port1 and port2 properties, which refer to linked MessagePort instances.

const { MessageChannel } = require('node:worker_threads');

const { port1, port2 } = new MessageChannel();
port1.on('message', (message) => console.log('received', message));
port2.postMessage({ foo: 'bar' });
// Prints: received { foo: 'bar' } from the `port1.on('message')` listener

MessageChannel class is a global reference for require('worker_threads').MessageChannel https://nodejs.org/api/globals.html#messagechannel