Bug 1725111 - [remote] Use contextDescriptor as broadcasting argument for MessageHandler commands r=webdriver-reviewers,whimboo

Instead of using a broadcast boolean flag in the CommandDestination, use a contextDescriptor.
The only context descriptor type supported here is CONTEXT_DESCRIPTOR_TYPES.ALL, and the behavior is unchanged.

Differential Revision: https://phabricator.services.mozilla.com/D131439

remote/shared/messagehandler/MessageHandler.jsm

@@ -169,9 +169,14 @@ class MessageHandler extends EventEmitter {
    * @typedef {Object} CommandDestination
    * @property {String} type
    *     One of MessageHandler.type.
-   * @property {String} id
+   * @property {String=} id
    *     Unique context identifier. The format depends on the type.
    *     For WINDOW_GLOBAL destinations, this is a browsing context id.
+   *     Optional, should only be provided if `contextDescriptor` is missing.
+   * @property {ContextDescriptor=} contextDescriptor
+   *     Descriptor used to match several contexts, which will all receive the
+   *     command.
+   *     Optional, should only be provided if `id` is missing.
    */
 
   /**

remote/shared/messagehandler/test/browser/broadcast/head.js

@@ -31,6 +31,9 @@ function sendTestBroadcastCommand(module, command, params, rootMessageHandler) {
   const { WindowGlobalMessageHandler } = ChromeUtils.import(
     "chrome://remote/content/shared/messagehandler/WindowGlobalMessageHandler.jsm"
   );
+  const { CONTEXT_DESCRIPTOR_TYPES } = ChromeUtils.import(
+    "chrome://remote/content/shared/messagehandler/MessageHandler.jsm"
+  );
 
   info("Send a test broadcast command");
   return rootMessageHandler.handleCommand({
@@ -38,8 +41,10 @@ function sendTestBroadcastCommand(module, command, params, rootMessageHandler) {
     commandName: command,
     params,
     destination: {
+      contextDescriptor: {
+        type: CONTEXT_DESCRIPTOR_TYPES.ALL,
+      },
       type: WindowGlobalMessageHandler.type,
-      broadcast: true,
     },
   });
 }

remote/shared/messagehandler/transports/FrameTransport.jsm

@@ -13,6 +13,8 @@ const { XPCOMUtils } = ChromeUtils.import(
 XPCOMUtils.defineLazyModuleGetters(this, {
   Services: "resource://gre/modules/Services.jsm",
 
+  CONTEXT_DESCRIPTOR_TYPES:
+    "chrome://remote/content/shared/messagehandler/MessageHandler.jsm",
   MessageHandlerFrameActor:
     "chrome://remote/content/shared/messagehandler/transports/js-window-actors/MessageHandlerFrameActor.jsm",
 });
@@ -46,9 +48,9 @@ class FrameTransport {
    *     being processed by WINDOW_GLOBAL MessageHandlers.
    */
   forwardCommand(command) {
-    if (command.destination.id && command.destination.broadcast) {
+    if (command.destination.id && command.destination.contextDescriptor) {
       throw new Error(
-        "Invalid command destination with both 'id' and 'broadcast' properties"
+        "Invalid command destination with both 'id' and 'contextDescriptor' properties"
       );
     }
 
@@ -63,18 +65,21 @@ class FrameTransport {
       return this._sendCommandToBrowsingContext(command, browsingContext);
     }
 
-    // ... otherwise broadcast to all registered destinations.
+    // ... otherwise broadcast to destinations matching the contextDescriptor.
-    if (command.destination.broadcast) {
+    if (command.destination.contextDescriptor) {
       return this._broadcastCommand(command);
     }
 
     throw new Error(
-      "Unrecognized command destination, missing 'id' or 'broadcast' properties"
+      "Unrecognized command destination, missing 'id' or 'contextDescriptor' properties"
     );
   }
 
   _broadcastCommand(command) {
-    const browsingContexts = this._getAllBrowsingContexts();
+    const { contextDescriptor } = command.destination;
+    const browsingContexts = this._getBrowsingContextsForDescriptor(
+      contextDescriptor
+    );
 
     return Promise.all(
       browsingContexts.map(async browsingContext => {
@@ -104,6 +109,18 @@ class FrameTransport {
     return `[object ${this.constructor.name} ${this._messageHandler.name}]`;
   }
 
+  _getBrowsingContextsForDescriptor(contextDescriptor) {
+    const { type } = contextDescriptor;
+    if (type === CONTEXT_DESCRIPTOR_TYPES.ALL) {
+      return this._getAllBrowsingContexts();
+    }
+
+    // TODO: Handle other types of context descriptors.
+    throw new Error(
+      `Unsupported contextDescriptor type for broadcasting: ${type}`
+    );
+  }
+
   _getAllBrowsingContexts() {
     let browsingContexts = [];
     // Fetch all top level window's browsing contexts

remote/webdriver-bidi/modules/root/log.jsm

@@ -11,6 +11,8 @@ const { XPCOMUtils } = ChromeUtils.import(
 );
 
 XPCOMUtils.defineLazyModuleGetters(this, {
+  CONTEXT_DESCRIPTOR_TYPES:
+    "chrome://remote/content/shared/messagehandler/MessageHandler.jsm",
   Module: "chrome://remote/content/shared/messagehandler/Module.jsm",
 });
 
@@ -30,7 +32,7 @@ class Log extends Module {
           moduleName: "log",
           category: "event",
           contextDescriptor: {
-            type: "all",
+            type: CONTEXT_DESCRIPTOR_TYPES.ALL,
           },
           values: ["log.entryAdded"],
         });