| // Copyright 2013 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef EXTENSIONS_BROWSER_LAZY_BACKGROUND_TASK_QUEUE_H_ |
| #define EXTENSIONS_BROWSER_LAZY_BACKGROUND_TASK_QUEUE_H_ |
| |
| #include <stddef.h> |
| |
| #include <map> |
| #include <string> |
| |
| #include "base/callback_forward.h" |
| #include "base/compiler_specific.h" |
| #include "base/gtest_prod_util.h" |
| #include "base/scoped_observer.h" |
| #include "components/keyed_service/core/keyed_service.h" |
| #include "content/public/browser/notification_observer.h" |
| #include "content/public/browser/notification_registrar.h" |
| #include "extensions/browser/extension_registry_observer.h" |
| #include "extensions/browser/lazy_context_task_queue.h" |
| #include "extensions/common/extension_id.h" |
| |
| namespace content { |
| class BrowserContext; |
| } |
| |
| namespace extensions { |
| class Extension; |
| class ExtensionHost; |
| class ExtensionRegistry; |
| class LazyContextId; |
| |
| // This class maintains a queue of tasks that should execute when an |
| // extension's lazy background page is loaded. It is also in charge of loading |
| // the page when the first task is queued. |
| // |
| // It is the consumer's responsibility to use this class when appropriate, i.e. |
| // only with extensions that have not-yet-loaded lazy background pages. |
| class LazyBackgroundTaskQueue : public KeyedService, |
| public LazyContextTaskQueue, |
| public content::NotificationObserver, |
| public ExtensionRegistryObserver { |
| public: |
| typedef base::Callback<void(ExtensionHost*)> PendingTask; |
| |
| explicit LazyBackgroundTaskQueue(content::BrowserContext* browser_context); |
| ~LazyBackgroundTaskQueue() override; |
| |
| // Convenience method to return the LazyBackgroundTaskQueue for a given |
| // |context|. |
| static LazyBackgroundTaskQueue* Get(content::BrowserContext* context); |
| |
| // Returns true if the task should be added to the queue (that is, if the |
| // extension has a lazy background page that isn't ready yet). If the |
| // extension has a lazy background page that is being suspended this method |
| // cancels that suspension. |
| bool ShouldEnqueueTask(content::BrowserContext* context, |
| const Extension* extension) override; |
| // TODO(lazyboy): Find a better way to use AddPendingTask instead of this. |
| // Currently AddPendingTask has lots of consumers that depend on |
| // ExtensionHost. |
| void AddPendingTaskToDispatchEvent( |
| LazyContextId* context_id, |
| const LazyContextTaskQueue::PendingTask& task) override; |
| |
| // Adds a task to the queue for a given extension. If this is the first |
| // task added for the extension, its lazy background page will be loaded. |
| // The task will be called either when the page is loaded, or when the |
| // page fails to load for some reason (e.g. a crash or browser |
| // shutdown). In the latter case, the ExtensionHost parameter is NULL. |
| void AddPendingTask( |
| content::BrowserContext* context, |
| const std::string& extension_id, |
| const PendingTask& task); |
| |
| private: |
| FRIEND_TEST_ALL_PREFIXES(LazyBackgroundTaskQueueTest, AddPendingTask); |
| FRIEND_TEST_ALL_PREFIXES(LazyBackgroundTaskQueueTest, ProcessPendingTasks); |
| |
| // A map between a BrowserContext/extension_id pair and the queue of tasks |
| // pending the load of its background page. |
| typedef std::pair<content::BrowserContext*, ExtensionId> PendingTasksKey; |
| typedef std::vector<PendingTask> PendingTasksList; |
| using PendingTasksMap = |
| std::map<PendingTasksKey, std::unique_ptr<PendingTasksList>>; |
| |
| // content::NotificationObserver interface. |
| void Observe(int type, |
| const content::NotificationSource& source, |
| const content::NotificationDetails& details) override; |
| |
| // ExtensionRegistryObserver interface. |
| void OnExtensionUnloaded(content::BrowserContext* browser_context, |
| const Extension* extension, |
| UnloadedExtensionReason reason) override; |
| |
| // Called when a lazy background page has finished loading, or has failed to |
| // load (host is NULL in that case). All enqueued tasks are run in order. |
| void ProcessPendingTasks( |
| ExtensionHost* host, |
| content::BrowserContext* context, |
| const Extension* extension); |
| |
| content::BrowserContext* browser_context_; |
| content::NotificationRegistrar registrar_; |
| PendingTasksMap pending_tasks_; |
| |
| ScopedObserver<ExtensionRegistry, ExtensionRegistryObserver> |
| extension_registry_observer_; |
| }; |
| |
| } // namespace extensions |
| |
| #endif // EXTENSIONS_BROWSER_LAZY_BACKGROUND_TASK_QUEUE_H_ |