1 files changed, 83 insertions, 4 deletions

diff --git a/lib/internal/worker/io.js b/lib/internal/worker/io.js
index 73958dbc2d7..2352ac6ebf8 100644
--- a/lib/internal/worker/io.js
+++ b/lib/internal/worker/io.js
@@ -19,11 +19,13 @@ const {
 const {
   MessagePort,
   MessageChannel,
+  broadcastChannel,
   drainMessagePort,
   moveMessagePortToContext,
   receiveMessageOnPort: receiveMessageOnPort_,
   stopMessagePort,
-  checkMessagePort
+  checkMessagePort,
+  DOMException,
 } = internalBinding('messaging');
 const {
   getEnvMessagePort
@@ -41,14 +43,20 @@ const {
 } = require('internal/event_target');
 const { inspect } = require('internal/util/inspect');
 const {
-  ERR_INVALID_ARG_TYPE
-} = require('internal/errors').codes;
+  codes: {
+    ERR_INVALID_ARG_TYPE,
+    ERR_MISSING_ARGS,
+  }
+} = require('internal/errors');
 
 const kData = Symbol('kData');
+const kHandle = Symbol('kHandle');
 const kIncrementsPortRef = Symbol('kIncrementsPortRef');
 const kLastEventId = Symbol('kLastEventId');
 const kName = Symbol('kName');
 const kOrigin = Symbol('kOrigin');
+const kOnMessage = Symbol('kOnMessage');
+const kOnMessageError = Symbol('kOnMessageError');
 const kPort = Symbol('kPort');
 const kPorts = Symbol('kPorts');
 const kWaitingStreams = Symbol('kWaitingStreams');
@@ -324,6 +332,76 @@ function receiveMessageOnPort(port) {
   return { message };
 }
 
+function onMessageEvent(type, data) {
+  this.dispatchEvent(new MessageEvent(type, { data }));
+}
+
+class BroadcastChannel extends EventTarget {
+  constructor(name) {
+    if (arguments.length === 0)
+      throw new ERR_MISSING_ARGS('name');
+    super();
+    this[kName] = `${name}`;
+    this[kHandle] = broadcastChannel(this[kName]);
+    this[kOnMessage] = onMessageEvent.bind(this, 'message');
+    this[kOnMessageError] = onMessageEvent.bind(this, 'messageerror');
+    this[kHandle].on('message', this[kOnMessage]);
+    this[kHandle].on('messageerror', this[kOnMessageError]);
+  }
+
+  [inspect.custom](depth, options) {
+    if (depth < 0)
+      return 'BroadcastChannel';
+
+    const opts = {
+      ...options,
+      depth: options.depth == null ? null : options.depth - 1
+    };
+
+    return `BroadcastChannel ${inspect({
+      name: this[kName],
+      active: this[kHandle] !== undefined,
+    }, opts)}`;
+  }
+
+  get name() { return this[kName]; }
+
+  close() {
+    if (this[kHandle] === undefined)
+      return;
+    this[kHandle].off('message', this[kOnMessage]);
+    this[kHandle].off('messageerror', this[kOnMessageError]);
+    this[kOnMessage] = undefined;
+    this[kOnMessageError] = undefined;
+    this[kHandle].close();
+    this[kHandle] = undefined;
+  }
+
+  postMessage(message) {
+    if (arguments.length === 0)
+      throw new ERR_MISSING_ARGS('message');
+    if (this[kHandle] === undefined)
+      throw new DOMException('BroadcastChannel is closed.');
+    if (this[kHandle].postMessage(message) === undefined)
+      throw new DOMException('Message could not be posted.');
+  }
+
+  ref() {
+    if (this[kHandle])
+      this[kHandle].ref();
+    return this;
+  }
+
+  unref() {
+    if (this[kHandle])
+      this[kHandle].unref();
+    return this;
+  }
+}
+
+defineEventHandler(BroadcastChannel.prototype, 'message');
+defineEventHandler(BroadcastChannel.prototype, 'messageerror');
+
 module.exports = {
   drainMessagePort,
   messageTypes,
@@ -339,5 +417,6 @@ module.exports = {
   setupPortReferencing,
   ReadableWorkerStdio,
   WritableWorkerStdio,
-  createWorkerStdio
+  createWorkerStdio,
+  BroadcastChannel,
 };