interface_sdk-js/api/@ohos.app.ability.appRecovery.d.ts

/*
 * Copyright (c) 2022 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License"),
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import UIAbilityContext from './application/UIAbilityContext';
import Want from './@ohos.app.ability.Want';

/**
 * This module provides the capability of app recovery.
 * You can use this capability to save state and restart the application
 * which let end user continue their workflow when app error occurs.
 * This api support restart the app when js crash or app freeze occurs currently.
 * @syscap SystemCapability.Ability.AbilityRuntime.Core
 * @since 9
 */
declare namespace appRecovery {
  /**
   * The flag that determines when to restart you app.
   * @enum { number }
   * @syscap SystemCapability.Ability.AbilityRuntime.Core
   * @since 9
   */
  enum RestartFlag {
    /**
     * No restart restrictions.
     */
    ALWAYS_RESTART = 0,

    /**
     * Restart if current app process encounter uncaught js/ts/ets exception.
     */
    RESTART_WHEN_JS_CRASH = 0x0001,

    /**
     * Restart if the main thread of current app process block more than 6 seconds.
     */
    RESTART_WHEN_APP_FREEZE = 0x0002,

    /**
     * Do not restart in any scenario.
     */
    NO_RESTART = 0xFFFF,
  }

  /**
   * The flag that determines when to save ability state.
   * When start saving ability state, the { ohos.app.ability.UiAbility.onSaveState } will be called and
   * the page stack of current ability will be saved automatically.
   * @enum { number }
   * @syscap SystemCapability.Ability.AbilityRuntime.Core
   * @since 9
   */
  enum SaveOccasionFlag {
    /**
     * Saving ability state when an error occurs.
     * The error in current situation has the same semantic with { errorManager } defines
     * which means the state that the application cannot continue to work but allows developer to handle.
     */
    SAVE_WHEN_ERROR = 0x0001,

    /**
     * Saving ability state when ability is in background.
     */
    SAVE_WHEN_BACKGROUND = 0x0002,
  }

  /**
   * The flag that determines how to save the ability state.
   * @enum { number }
   * @syscap SystemCapability.Ability.AbilityRuntime.Core
   * @since 9
   */
  enum SaveModeFlag {
    /**
     * Save state to file immediately.
     */
    SAVE_WITH_FILE = 0x0001,

    /**
     * Keep state in memory and flush to file when error occurs or { restartApp } is invoked.
     */
    SAVE_WITH_SHARED_MEMORY = 0x0002,
  }

  /**
   * Enable appRecovery function.
   * @param { RestartFlag } The flag that determines the restart cases of your app, default value is { ALWAYS_RESTART }.
   * @param { SaveOccasionFlag } The flag that determines when to save ability state, default value is { SAVE_WHEN_ERROR }.
   * @param { SaveModeFlag } The flag that determines how to save the ability state, default value is { SAVE_WITH_FILE }.
   * @syscap SystemCapability.Ability.AbilityRuntime.Core
   * @StageModelOnly
   * @since 9
   */
  function enableAppRecovery(restart?: RestartFlag, saveOccasion?: SaveOccasionFlag, saveMode?: SaveModeFlag): void;

  /**
   * Restart current process and launch the first ability(the entry ability in most cases) of current process.
   * The previous saved state will be filled in the { want.wantParams } of { UIAbility.onCreate } interface.
   * and the { param } of { UIAbility.onCreate } will be set to APP_RECOVERY.
   * @syscap SystemCapability.Ability.AbilityRuntime.Core
   * @StageModelOnly
   * @since 9
   */
  function restartApp(): void;

  /**
   * Set the want that will be used when app restart initiated by appRecovery.
   * @param { Want } want that defines the ability you want to start
   * @syscap SystemCapability.Ability.AbilityRuntime.Core
   * @StageModelOnly
   * @since 10
   */
  function setRestartWant(want: Want): void;

  /**
   * Actively save application state.
   * The ability framework will call { UIAbility.onSaveState } of first launched ability and
   * persist state as { saveOccasion } flag from { enableAppRecovery } interface.
   * @returns true if save data successfully, otherwise false.
   * @syscap SystemCapability.Ability.AbilityRuntime.Core
   * @StageModelOnly
   * @since 9
   */
  function saveAppState(): boolean;
  /**
   * Save the ability state according to the context.
   * @param { UIAbilityContext } [context] - context indicates the ability context you want to save state.
   * If context is not specified, the onSaveState will be invoked on all the recoverable abilities in current process.
   * @returns true if save data successfully, otherwise false.
   * @syscap SystemCapability.Ability.AbilityRuntime.Core
   * @StageModelOnly
   * @since 10
   */
  function saveAppState(context?: UIAbilityContext): boolean;
}

export default appRecovery;