callback_command.h | Explore in Territory

// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_WEB_APPLICATIONS_COMMANDS_INTERNAL_CALLBACK_COMMAND_H_
#define CHROME_BROWSER_WEB_APPLICATIONS_COMMANDS_INTERNAL_CALLBACK_COMMAND_H_

#include <memory>
#include <string>
#include <tuple>
#include <type_traits>

#include "base/functional/callback.h"
#include "base/values.h"
#include "chrome/browser/web_applications/commands/command_result.h"
#include "chrome/browser/web_applications/commands/internal/command_internal.h"
#include "chrome/browser/web_applications/commands/web_app_command.h"
#include "chrome/browser/web_applications/locks/all_apps_lock.h"
#include "chrome/browser/web_applications/locks/app_lock.h"
#include "chrome/browser/web_applications/locks/noop_lock.h"
#include "chrome/browser/web_applications/locks/shared_web_contents_lock.h"
#include "chrome/browser/web_applications/locks/shared_web_contents_with_app_lock.h"

namespace web_app::internal {

// The callback commands allow simple operations that don't involve asynchronous
// work to be commands without needing to create a dedicated class, but still
// offer all of the advantages of commands. All "callback commands" take two
// callbacks, the one to be run as the command, and the one to be run on
// completion. There are specializations here to allow different types of
// completion callback support:
// - CallbackCommand: Equivalent of base::PostTakeAndReply. This is used for
//                    completion callbacks that are simple closures - they don't
//                    take any results from the command callback.
// - CallbackCommandWithResult: Equivalent of base::PostTakeAndReplyWithResult.
//                              This is used if the completion callback takes a
//                              single argument, and thus the command callback
//                              can return that single argument.
//
// For a solution that allows multiple return values / multiple arguments in the
// completion callback, see this file in https://crrev.com/c/5105100/6/.
//
// Note: Prefer using WebAppCommandScheduler::ScheduleCallbackWithLock
// instead of this class directly.
template <typename LockType>
class CallbackCommand : public WebAppCommand<LockType> { … };

// Equivalent of base::PostTaskAndReplyWithResult for the command system.
template <typename LockType, typename ItemType>
class CallbackCommandWithResult : public WebAppCommand<LockType, ItemType> { … };

}  // namespace web_app::internal

#endif  // CHROME_BROWSER_WEB_APPLICATIONS_COMMANDS_INTERNAL_CALLBACK_COMMAND_H_
chromium/chrome/browser/web_applications/commands/internal/callback_command.h
