feat: support goog:channel along with channel (#2996)

Step towards addressing
#2840

src/bidiMapper/BidiServer.ts

@@ -68,11 +68,8 @@ export class BidiServer extends EventEmitter<BidiServerEvent> {
   };
 
   #processOutgoingMessage = async (messageEntry: OutgoingMessage) => {
-    const message = messageEntry.message;
-
-    if (messageEntry.channel !== null) {
-      message['channel'] = messageEntry.channel;
-    }
+    // Enrich message with channel data.
+    const message = {...messageEntry.message, ...messageEntry.channel};
 
     await this.#transport.sendMessage(message);
   };

src/bidiMapper/OutgoingMessage.ts

@@ -23,10 +23,7 @@ export class OutgoingMessage {
   readonly #message: ChromiumBidi.Message;
   readonly #channel: BidiPlusChannel;
 
-  private constructor(
-    message: ChromiumBidi.Message,
-    channel: BidiPlusChannel = null,
-  ) {
+  private constructor(message: ChromiumBidi.Message, channel: BidiPlusChannel) {
     this.#message = message;
     this.#channel = channel;
   }
@@ -48,7 +45,7 @@ export class OutgoingMessage {
 
   static createResolved(
     message: ChromiumBidi.Message,
-    channel?: BidiPlusChannel,
+    channel: BidiPlusChannel,
   ): Promise<Result<OutgoingMessage>> {
     return Promise.resolve({
       kind: 'success',

src/bidiMapper/modules/network/NetworkStorage.spec.ts

@@ -93,7 +93,7 @@ describe('NetworkStorage', () => {
       // Verify that the Request send the message
       // To the correct context
       [MockCdpNetworkEvents.defaultFrameId],
-      null,
+      {},
     );
     eventManager.on(EventManagerEvents.Event, ({message, event}) => {
       processingQueue.add(message, event);

src/bidiMapper/modules/session/EventManager.ts

@@ -103,11 +103,11 @@ export class EventManager extends EventEmitter<EventManagerEventsMap> {
    */
   #eventBuffers = new Map<string, Buffer<EventWrapper>>();
   /**
-   * Maps `eventName` + `browsingContext` to  Map of channel to last id
+   * Maps `eventName` + `browsingContext` to  Map of json stringified channel to last id.
    * Used to avoid sending duplicated events when user
    * subscribes -> unsubscribes -> subscribes.
    */
-  #lastMessageSent = new Map<string, Map<string | null, number>>();
+  #lastMessageSent = new Map<string, Map<string, number>>();
   #subscriptionManager: SubscriptionManager;
   #browsingContextStorage: BrowsingContextStorage;
   /**
@@ -366,15 +366,19 @@ export class EventManager extends EventEmitter<EventManagerEventsMap> {
     );
 
     const lastId = Math.max(
-      this.#lastMessageSent.get(lastSentMapKey)?.get(channel) ?? 0,
+      this.#lastMessageSent.get(lastSentMapKey)?.get(JSON.stringify(channel)) ??
+        0,
       eventWrapper.id,
     );
 
     const channelMap = this.#lastMessageSent.get(lastSentMapKey);
     if (channelMap) {
-      channelMap.set(channel, lastId);
+      channelMap.set(JSON.stringify(channel), lastId);
     } else {
-      this.#lastMessageSent.set(lastSentMapKey, new Map([[channel, lastId]]));
+      this.#lastMessageSent.set(
+        lastSentMapKey,
+        new Map([[JSON.stringify(channel), lastId]]),
+      );
     }
   }
 
@@ -388,7 +392,8 @@ export class EventManager extends EventEmitter<EventManagerEventsMap> {
   ): EventWrapper[] {
     const bufferMapKey = EventManager.#getMapKey(eventName, contextId);
     const lastSentMessageId =
-      this.#lastMessageSent.get(bufferMapKey)?.get(channel) ?? -Infinity;
+      this.#lastMessageSent.get(bufferMapKey)?.get(JSON.stringify(channel)) ??
+      -Infinity;
 
     const result: EventWrapper[] =
       this.#eventBuffers

src/bidiMapper/modules/session/SessionProcessor.ts

@@ -144,7 +144,7 @@ export class SessionProcessor {
 
   async subscribe(
     params: Session.SubscriptionRequest,
-    channel: BidiPlusChannel = null,
+    channel: BidiPlusChannel = {},
   ): Promise<Session.SubscribeResult> {
     const subscription = await this.#eventManager.subscribe(
       params.events as ChromiumBidi.EventNames[],
@@ -158,7 +158,7 @@ export class SessionProcessor {
 
   async unsubscribe(
     params: Session.SubscriptionRequest,
-    channel: BidiPlusChannel = null,
+    channel: BidiPlusChannel = {},
   ): Promise<EmptyResult> {
     await this.#eventManager.unsubscribe(
       params.events as ChromiumBidi.EventNames[],

src/bidiMapper/modules/session/SubscriptionManager.spec.ts

@@ -41,8 +41,8 @@ const SOME_NESTED_CONTEXT = 'SOME_NESTED_CONTEXT';
 const ANOTHER_CONTEXT = 'ANOTHER_CONTEXT';
 const ANOTHER_NESTED_CONTEXT = 'ANOTHER_NESTED_CONTEXT';
 
-const SOME_CHANNEL = 'SOME_CHANNEL';
-const ANOTHER_CHANNEL = 'ANOTHER_CHANNEL';
+const SOME_CHANNEL = {'goog:channel': 'SOME_CHANNEL'};
+const ANOTHER_CHANNEL = {'goog:channel': 'ANOTHER_CHANNEL'};
 
 describe('SubscriptionManager', () => {
   let subscriptionManager: SubscriptionManager;

src/bidiMapper/modules/session/SubscriptionManager.ts

@@ -95,29 +95,39 @@ export class SubscriptionManager {
     eventName: ChromiumBidi.EventNames,
     contextId: BrowsingContext.BrowsingContext,
   ): BidiPlusChannel[] {
-    const channels = new Set<BidiPlusChannel>();
+    // Maps JSON stringified channel to a channel.
+    // TODO: switch to `Set` of `goog:channel` once legacy `channel` is removed.
+    const channels = new Map<string, BidiPlusChannel>();
 
     for (const subscription of this.#subscriptions) {
       if (this.#isSubscribedTo(subscription, eventName, contextId)) {
-        channels.add(subscription.channel);
+        channels.set(
+          JSON.stringify(subscription.channel),
+          subscription.channel,
+        );
       }
     }
 
-    return Array.from(channels);
+    return Array.from(channels.values());
   }
 
   getChannelsSubscribedToEventGlobally(
     eventName: ChromiumBidi.EventNames,
   ): BidiPlusChannel[] {
-    const channels = new Set<BidiPlusChannel>();
+    // Maps JSON stringified channel to a channel.
+    // TODO: switch to `Set` of `goog:channel` once legacy `channel` is removed.
+    const channels = new Map<string, BidiPlusChannel>();
 
     for (const subscription of this.#subscriptions) {
       if (this.#isSubscribedTo(subscription, eventName)) {
-        channels.add(subscription.channel);
+        channels.set(
+          JSON.stringify(subscription.channel),
+          subscription.channel,
+        );
       }
     }
 
-    return Array.from(channels);
+    return Array.from(channels.values());
   }
 
   #isSubscribedTo(
@@ -249,7 +259,8 @@ export class SubscriptionManager {
     const eventsMatched = new Set<ChromiumBidi.EventNames>();
     const contextsMatched = new Set<BrowsingContext.BrowsingContext>();
     for (const subscription of this.#subscriptions) {
-      if (subscription.channel !== channel) {
+      // `channel` is undefined or an object with 1 field, so `JSON.stringify` is stable.
+      if (JSON.stringify(subscription.channel) !== JSON.stringify(channel)) {
         newSubscriptions.push(subscription);
         continue;
       }

src/bidiTab/Transport.ts

@@ -41,7 +41,7 @@ export class WindowBidiTransport implements BidiTransport {
       } catch (e: unknown) {
         const error = e instanceof Error ? e : new Error(e as string);
         // Transport-level error does not provide channel.
-        this.#respondWithError(message, ErrorCode.InvalidArgument, error, null);
+        this.#respondWithError(message, ErrorCode.InvalidArgument, error, {});
       }
     };
   }
@@ -73,14 +73,10 @@ export class WindowBidiTransport implements BidiTransport {
       error,
     );
 
-    if (channel) {
-      this.sendMessage({
-        ...errorResponse,
-        channel,
-      });
-    } else {
-      this.sendMessage(errorResponse);
-    }
+    this.sendMessage({
+      ...errorResponse,
+      ...(channel ?? {}),
+    });
   }
 
   static #getJsonType(value: unknown) {
@@ -120,7 +116,13 @@ export class WindowBidiTransport implements BidiTransport {
   }
 
   static #parseBidiMessage(message: string): ChromiumBidi.Command {
-    let command: ChromiumBidi.Command;
+    let command: {
+      id?: unknown;
+      method?: unknown;
+      params?: unknown;
+      channel?: unknown;
+      'goog:channel'?: unknown;
+    };
     try {
       command = JSON.parse(message);
     } catch {
@@ -136,7 +138,7 @@ export class WindowBidiTransport implements BidiTransport {
     const {id, method, params} = command;
 
     const idType = WindowBidiTransport.#getJsonType(id);
-    if (idType !== 'number' || !Number.isInteger(id) || id < 0) {
+    if (idType !== 'number' || !Number.isInteger(id) || (id as number) < 0) {
       // TODO: should uint64_t be the upper limit?
       // https://tools.ietf.org/html/rfc7049#section-2.1
       throw new Error(`Expected unsigned integer but got ${idType}`);
@@ -152,15 +154,26 @@ export class WindowBidiTransport implements BidiTransport {
       throw new Error(`Expected object params but got ${paramsType}`);
     }
 
-    let channel = command.channel;
-    if (channel !== undefined) {
-      const channelType = WindowBidiTransport.#getJsonType(channel);
+    let channel: BidiPlusChannel = {};
+    if (command['goog:channel'] !== undefined) {
+      const channelType = WindowBidiTransport.#getJsonType(
+        command['goog:channel'],
+      );
+      if (channelType !== 'string') {
+        throw new Error(
+          `Expected string value of 'goog:channel' but got ${channelType}`,
+        );
+      }
+      if (command['goog:channel'] !== '') {
+        channel = {'goog:channel': command['goog:channel'] as string};
+      }
+    } else if (command.channel !== undefined) {
+      const channelType = WindowBidiTransport.#getJsonType(command.channel);
       if (channelType !== 'string') {
-        throw new Error(`Expected string channel but got ${channelType}`);
+        throw new Error(`Expected string 'channel' but got ${channelType}`);
       }
-      // Empty string channel is considered as no channel provided.
-      if (channel === '') {
-        channel = undefined;
+      if (command.channel !== '') {
+        channel = {channel: command.channel as string};
       }
     }
 

src/protocol/chromium-bidi.ts

@@ -127,9 +127,7 @@ export type Command = (
       // not re-define it. Therefore, it's not part of generated types.
       id: WebDriverBidi.JsUint;
     } & WebDriverBidiBluetooth.Bluetooth.SimulateAdvertisement)
-) & {
-  channel?: WebDriverBidi.Script.Channel;
-};
+) & {channel: BidiPlusChannel};
 
 export type CommandResponse =
   | WebDriverBidi.CommandResponse
@@ -153,8 +151,22 @@ export const EVENT_NAMES = new Set([
 
 export type ResultData = WebDriverBidi.ResultData | Cdp.ResultData;
 
-export type BidiPlusChannel = string | null;
+// TODO: replace with optional string once legacy `channel` is removed.
+export type BidiPlusChannel =
+  | {
+      'goog:channel': string;
+      channel?: never;
+    }
+  | {
+      'goog:channel'?: never;
+      channel: string;
+    }
+  | {
+      'goog:channel'?: never;
+      channel?: never;
+    };
 
 export type Message = (WebDriverBidi.Message | Cdp.Message | BluetoothEvent) & {
-  channel?: BidiPlusChannel;
+  channel?: string;
+  'goog:channel'?: string;
 };