http: expose websockets

PR-URL: https://github.com/nodejs/node/pull/53721
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Paolo Insogna <paolo@cowtech.it>
Reviewed-By: James M Snell <jasnell@gmail.com>

lib/http.js

@@ -42,6 +42,7 @@ const {
   ServerResponse,
 } = require('_http_server');
 let maxHeaderSize;
+let undici;
 
 /**
  * Returns a new instance of `http.Server`.
@@ -114,6 +115,14 @@ function get(url, options, cb) {
   return req;
 }
 
+/**
+ * Lazy loads WebSocket, CloseEvent and MessageEvent classes from undici
+ * @returns {object} An object containing WebSocket, CloseEvent, and MessageEvent classes.
+ */
+function lazyUndici() {
+  return undici ??= require('internal/deps/undici/undici');
+}
+
 module.exports = {
   _connectionListener,
   METHODS: methods.toSorted(),
@@ -160,3 +169,30 @@ ObjectDefineProperty(module.exports, 'globalAgent', {
     httpAgent.globalAgent = value;
   },
 });
+
+ObjectDefineProperty(module.exports, 'WebSocket', {
+  __proto__: null,
+  configurable: true,
+  enumerable: true,
+  get() {
+    return lazyUndici().WebSocket;
+  },
+});
+
+ObjectDefineProperty(module.exports, 'CloseEvent', {
+  __proto__: null,
+  configurable: true,
+  enumerable: true,
+  get() {
+    return lazyUndici().CloseEvent;
+  },
+});
+
+ObjectDefineProperty(module.exports, 'MessageEvent', {
+  __proto__: null,
+  configurable: true,
+  enumerable: true,
+  get() {
+    return lazyUndici().MessageEvent;
+  },
+});