chromium/content/browser/background_fetch/storage/database_task.h

// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_BACKGROUND_FETCH_STORAGE_DATABASE_TASK_H_
#define CONTENT_BROWSER_BACKGROUND_FETCH_STORAGE_DATABASE_TASK_H_

#include <memory>
#include <set>
#include <string>

#include "base/memory/raw_ptr.h"
#include "base/memory/scoped_refptr.h"
#include "content/browser/background_fetch/background_fetch.pb.h"
#include "content/browser/background_fetch/background_fetch_registration_id.h"
#include "mojo/public/cpp/bindings/associated_remote.h"
#include "third_party/blink/public/common/service_worker/service_worker_status_code.h"
#include "third_party/blink/public/mojom/background_fetch/background_fetch.mojom.h"
#include "third_party/blink/public/mojom/cache_storage/cache_storage.mojom.h"

namespace blink {
class StorageKey;
}  // namespace blink

namespace storage {
class QuotaManagerProxy;
}  // namespace storage

namespace content {

class BackgroundFetchDataManager;
class ChromeBlobStorageContext;
class ServiceWorkerContextWrapper;

// Note that this also handles non-error cases where the NONE is NONE.
HandleBackgroundFetchErrorCallback;

namespace background_fetch {

class DatabaseTask;

// A DatabaseTaskHost is the entity responsible for scheduling and running
// DatabaseTasks, usually the BackgroundFetchDataManager. Note that a
// DatabaseTask can be a DatabaseTaskHost, in order to run subtasks.
class DatabaseTaskHost { … };

// A DatabaseTask is an asynchronous "transaction" that needs to read/write the
// Service Worker Database.
//
// Only one DatabaseTask can run at once per StoragePartition, and no other code
// reads/writes Background Fetch keys, so each task effectively has an exclusive
// lock, except that core Service Worker code may delete all keys for a
// ServiceWorkerRegistration or the entire database at any time.
//
// A DatabaseTask can also optionally run other DatabaseTasks as subtasks. This
// allows us to re-use commonly used DatabaseTasks. Subtasks are started as soon
// as they are added, and cannot outlive the parent DatabaseTask.
class DatabaseTask : public DatabaseTaskHost { … };

}  // namespace background_fetch

}  // namespace content

#endif  // CONTENT_BROWSER_BACKGROUND_FETCH_STORAGE_DATABASE_TASK_H_