event_router.mojom | Explore in Territory

// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module extensions.mojom;

import "mojo/public/mojom/base/values.mojom";
import "url/mojom/url.mojom";

// The context that owns the event listener. This can either be an extension,
// indicated by `extension_id`, or a web page, indicated by `listener_url`.
union EventListenerOwner {
  string extension_id;
  url.mojom.Url listener_url;
};

// Details about a running javascript context for an extension service worker.
struct ServiceWorkerContext {
  // The scope associated with the extension service worker.
  // This should generally be the extension root scope.
  url.mojom.Url scope_url;
  // The service worker version.
  int64 version_id;
  // The thread ID for the worker running in the renderer.
  int32 thread_id;
};

// Details about a listener for a given event.
struct EventListener {
  // The owner of the event listener, either an extension or a web page.
  EventListenerOwner listener_owner;
  // The event name for which the listener was added.
  string event_name;
  // Details about the service worker context, if and only if this listener was
  // added by an extension service worker.
  ServiceWorkerContext? service_worker_context;
  // The event filter for the listener, if and only if this was for a filtered
  // event.
  mojo_base.mojom.DictionaryValue? filter;
};

// Implemented in the browser, this interface defines methods for handling
// event router messages from the main thread or service worker.
interface EventRouter {
  // Notifies the browser that a new `event_listener` has been added.
  AddListenerForMainThread(EventListener event_listener);

  // Notifies the browser that the given extension added a listener to an event
  // in a service worker.
  AddListenerForServiceWorker(EventListener event_listener);

  // Notifies the browser that the given extension added a listener to an event
  // from a lazy background page.
  AddLazyListenerForMainThread(string extension_id,
                               string event_name);

  // Notifies the browser that the given extension added a listener to an event
  // from an extension service worker.
  AddLazyListenerForServiceWorker(string extension_id,
                                  url.mojom.Url worker_scope_url,
                                  string event_name);

  // Notifies the browser that the given `extension_id` or `listener_url` added
  // a listener to instances of the named event that satisfy the filter. If it
  // has `extension_id` in `listener_owner`, the listener is added for the
  // extension. Otherwise, it has a `listener_url` in `listener_owner` and the
  // listener is added for the URL.
  AddFilteredListenerForMainThread(
      EventListenerOwner listener_owner,
      string event_name,
      mojo_base.mojom.DictionaryValue filter,
      bool add_lazy_listener);

  // Notifies the browser that the given extension added a listener for a
  // service worker to instances of the named event that satisfy the filter.
  AddFilteredListenerForServiceWorker(
      string extension_id,
      string event_name,
      ServiceWorkerContext service_worker_context,
      mojo_base.mojom.DictionaryValue filter,
      bool add_lazy_listener);

  // Notifies the browser that an `event_listener` has been removed.
  RemoveListenerForMainThread(EventListener event_listener);

  // Notifies the browser that the given extension removed a listener from an
  // event in a service worker.
  RemoveListenerForServiceWorker(EventListener event_listener);

  // Notifies the browser that the given extension is no longer interested in
  // receiving the given event from a lazy background page.
  RemoveLazyListenerForMainThread(string extension_id,
                                  string event_name);

  // Notifies the browser that the given extension is no longer interested in
  // receiving the given event from an extension service worker.
  RemoveLazyListenerForServiceWorker(string extension_id,
                                     url.mojom.Url worker_scope_url,
                                     string event_name);

  // Notifies the browser that the given `extension_id` or `listener_url` is no
  // longer interested in instances of the named event that satisfy the filter.
  // If it has `extension_id` in `listener_owner`, the listener is removed for
  // the extension. Otherwise, it has a `listener_url` in `listener_owner` and
  // the listener is removed for the URL.
  RemoveFilteredListenerForMainThread(
      EventListenerOwner listener_owner,
      string event_name,
      mojo_base.mojom.DictionaryValue filter,
      bool remove_lazy_listener);

  // Notifies the browser that the given extension is no longer interested in
  // instances of the named event that satisfy the filter from an extension
  // service worker.
  RemoveFilteredListenerForServiceWorker(
      string extension_id,
      string event_name,
      ServiceWorkerContext service_worker_context,
      mojo_base.mojom.DictionaryValue filter,
      bool remove_lazy_listener);

};
chromium/extensions/common/mojom/event_router.mojom
