HarmonyOS Next 应用元服务开发-分布式数据对象迁移数据权限与基础数据

import { distributedDataObject } from '@kit.ArkData';
import { UIAbility, AbilityConstant } from '@kit.AbilityKit';
import { BusinessError } from '@kit.BasicServicesKit';
import { hilog } from '@kit.PerformanceAnalysisKit';
const TAG: string = '[MigrationAbility]';
const DOMAIN_NUMBER: number = 0xFF00;

// 业务数据定义
class ParentObject {
  mother: string
  father: string

  constructor(mother: string, father: string) {
    this.mother = mother
    this.father = father
  }
}

// 支持字符、数字、布尔值、对象的传递
class SourceObject {
  name: string | undefined
  age: number | undefined
  isVis: boolean | undefined
  parent: ParentObject | undefined

  constructor(name: string | undefined, age: number | undefined, isVis: boolean | undefined, parent: ParentObject | undefined) {
    this.name = name
    this.age = age
    this.isVis = isVis
    this.parent = parent
  }
}

export default class MigrationAbility extends UIAbility {
  d_object?: distributedDataObject.DataObject;

  async onContinue(wantParam: Record<string, Object>): Promise<AbilityConstant.OnContinueResult> {
    // ...
    let parentSource: ParentObject = new ParentObject('jack mom', 'jack Dad');
    let source: SourceObject = new SourceObject("jack", 18, false, parentSource);

    // 创建分布式数据对象
    this.d_object = distributedDataObject.create(this.context, source);

    // 生成数据对象组网id，激活分布式数据对象
    let dataSessionId: string = distributedDataObject.genSessionId();
    this.d_object.setSessionId(dataSessionId);

    // 将组网id存在want中传递到对端
    wantParam['dataSessionId'] = dataSessionId;

    // 数据对象持久化，确保迁移后即使应用退出，对端依然能够恢复数据对象
    // 从wantParam.targetDevice中获取到对端设备的networkId作为入参
    await this.d_object.save(wantParam.targetDevice as string).then((result:
      distributedDataObject.SaveSuccessResponse) => {
      hilog.info(DOMAIN_NUMBER, TAG, `Succeeded in saving. SessionId: ${result.sessionId},
        version:${result.version}, deviceId:${result.deviceId}`);
    }).catch((err: BusinessError) => {
      hilog.error(DOMAIN_NUMBER, TAG, 'Failed to save. Error: ', JSON.stringify(err) ?? '');
    });
  }
}

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.

import { AbilityConstant, UIAbility, Want } from '@kit.AbilityKit';
import { distributedDataObject } from '@kit.ArkData';
import { hilog } from '@kit.PerformanceAnalysisKit';
const TAG: string = '[MigrationAbility]';
const DOMAIN_NUMBER: number = 0xFF00;

// 示例数据对象定义与上同

export default class MigrationAbility extends UIAbility {
  d_object?: distributedDataObject.DataObject;

  onCreate(want: Want, launchParam: AbilityConstant.LaunchParam): void {
    if (launchParam.launchReason === AbilityConstant.LaunchReason.CONTINUATION) {
      // ...
      // 调用封装好的分布式数据对象处理函数
      this.handleDistributedData(want);
    }
  }

  onNewWant(want: Want, launchParam: AbilityConstant.LaunchParam): void {
    if (launchParam.launchReason === AbilityConstant.LaunchReason.CONTINUATION) {
      if (want.parameters !== undefined) {
        // ...
        // 调用封装好的分布式数据对象处理函数
        this.handleDistributedData(want);
      }
    }
  }

  handleDistributedData(want: Want) {
    // 创建空的分布式数据对象
    let remoteSource: SourceObject = new SourceObject(undefined, undefined, undefined, undefined);
    this.d_object = distributedDataObject.create(this.context, remoteSource);

    // 读取分布式数据对象组网id
    let dataSessionId = '';
    if (want.parameters !== undefined) {
      dataSessionId = want.parameters.dataSessionId as string;
    }
    // 添加数据变更监听
    this.d_object.on("status", (sessionId: string, networkId: string, status: 'online' | 'offline' | 'restored') => {
      hilog.info(DOMAIN_NUMBER, TAG, "status changed " + sessionId + " " + status + " " + networkId);
      if (status == 'restored') {
        if (this.d_object) {
          // 收到迁移恢复的状态时，可以从分布式数据对象中读取数据
          hilog.info(DOMAIN_NUMBER, TAG, "restored name:" + this.d_object['name']);
          hilog.info(DOMAIN_NUMBER, TAG, "restored parents:" + JSON.stringify(this.d_object['parent']));
        }
      }

    // 激活分布式数据对象
    this.d_object.setSessionId(dataSessionId);
  }
}

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.