# 管理群组关键资产(C/C++)

<!--Kit: Asset Store Kit-->
<!--Subsystem: Security-->
<!--Owner: @JeremyXu-->
<!--Designer: @skye_you-->
<!--Tester: @nacyli-->
<!--Adviser: @zengyawen-->

以下为管理群组关键资产使用示例，请先查看开发指导：

- [新增关键资产(C/C++)](asset-native-add.md)
- [删除关键资产(C/C++)](asset-native-remove.md)
- [更新关键资产(C/C++)](asset-native-update.md)
- [查询关键资产(C/C++)](asset-native-query.md)

## 前置条件

在应用配置文件app.json5中，配置群组ID：demo_group_id。

```json
{
  "app": {
    // 其他配置项此处省略。
    "assetAccessGroups": [
      "demo_group_id"
    ]
  }
}
```

## 新增群组关键资产

在群组中新增密码为demo_pwd、别名为demo_alias、附属信息为demo_label的关键资产。用户首次解锁设备后，该关键资产可被访问。

```c
#include <string.h>

#include "asset/asset_api.h"

static napi_value AddAsset(napi_env env, napi_callback_info info)
{
    static const char *SECRET = "demo_pwd";
    static const char *ALIAS = "demo_alias";
    static const char *LABEL = "demo_label";
    static const char *GROUP_ID = "demo_group_id";

    Asset_Blob secret = {(uint32_t)(strlen(SECRET)), (uint8_t *)SECRET};
    Asset_Blob alias = {(uint32_t)(strlen(ALIAS)), (uint8_t *)ALIAS};
    Asset_Blob label = {(uint32_t)(strlen(LABEL)), (uint8_t *)LABEL};
    Asset_Blob group_id = { (uint32_t)(strlen(GROUP_ID)), (uint8_t *)GROUP_ID};
    Asset_Attr attr[] = {
        {.tag = ASSET_TAG_ACCESSIBILITY, .value.u32 = ASSET_ACCESSIBILITY_DEVICE_FIRST_UNLOCKED},
        {.tag = ASSET_TAG_SECRET, .value.blob = secret},
        {.tag = ASSET_TAG_ALIAS, .value.blob = alias},
        {.tag = ASSET_TAG_DATA_LABEL_NORMAL_1, .value.blob = label},
        {.tag = ASSET_TAG_GROUP_ID, .value.blob = group_id},
    };

    int32_t addResult = OH_Asset_Add(attr, sizeof(attr) / sizeof(attr[0]));
    napi_value ret;
    napi_create_int32(env, addResult, &ret);
    return ret;
}
```

## 删除群组关键资产

在群组中删除别名是demo_alias的关键资产。

```c
#include <string.h>

#include "asset/asset_api.h"

static napi_value RemoveAsset(napi_env env, napi_callback_info info)
{
    static const char *ALIAS = "demo_alias";
    static const char *GROUP_ID = "demo_group_id";

    Asset_Blob alias = {(uint32_t)(strlen(ALIAS)), (uint8_t *)ALIAS};
    Asset_Blob group_id = {(uint32_t)(strlen(GROUP_ID)), (uint8_t *)GROUP_ID};
    Asset_Attr attr[] = {
        {.tag = ASSET_TAG_ALIAS, .value.blob = alias}, // 此处指定别名删除单条群组关键资产，也可不指定别名删除多条群组关键资产。
        {.tag = ASSET_TAG_GROUP_ID, .value.blob = group_id},
    };

    int32_t removeResult = OH_Asset_Remove(attr, sizeof(attr) / sizeof(attr[0]));
    napi_value ret;
    napi_create_int32(env, removeResult, &ret);
    return ret;
}
```

## 更新群组关键资产

在群组中更新别名为demo_alias的关键资产，将关键资产的明文更新为demo_pwd_new，附属信息更新为demo_label_new。

```c
#include <string.h>

#include "asset/asset_api.h"

static napi_value UpdateAsset(napi_env env, napi_callback_info info)
{
    static const char *ALIAS = "demo_alias";
    static const char *SECRET = "demo_pwd_new";
    static const char *LABEL = "demo_label_new";
    static const char *GROUP_ID = "demo_group_id";

    Asset_Blob alias = {(uint32_t)(strlen(ALIAS)), (uint8_t *)ALIAS};
    Asset_Blob new_secret = {(uint32_t)(strlen(SECRET)), (uint8_t *)SECRET};
    Asset_Blob new_label = {(uint32_t)(strlen(LABEL)), (uint8_t *)LABEL};
    Asset_Blob group_id = {(uint32_t)(strlen(GROUP_ID)), (uint8_t *)GROUP_ID};
    Asset_Attr query[] = {
        {.tag = ASSET_TAG_ALIAS, .value.blob = alias},
        {.tag = ASSET_TAG_GROUP_ID, .value.blob = group_id},
    };
    Asset_Attr attributesToUpdate[] = {
        {.tag = ASSET_TAG_SECRET, .value.blob = new_secret},
        {.tag = ASSET_TAG_DATA_LABEL_NORMAL_1, .value.blob = new_label},
    };

    int32_t updateResult = OH_Asset_Update(query, sizeof(query) / sizeof(query[0]), attributesToUpdate,
                                           sizeof(attributesToUpdate) / sizeof(attributesToUpdate[0]));
    napi_value ret;
    napi_create_int32(env, updateResult, &ret);
    return ret;
}
```

## 查询单条群组关键资产明文

在群组中查询别名为demo_alias的关键资产明文。

```c
#include <string.h>

#include "asset/asset_api.h"

static napi_value QueryAsset(napi_env env, napi_callback_info info)
{
    static const char *ALIAS = "demo_alias";
    static const char *GROUP_ID = "demo_group_id";
    Asset_Blob alias = { (uint32_t)(strlen(ALIAS)), (uint8_t *)ALIAS };
    Asset_Blob group_id = { (uint32_t)(strlen(GROUP_ID)), (uint8_t *)GROUP_ID };
    Asset_Attr attr[] = {
        {.tag = ASSET_TAG_ALIAS, .value.blob = alias}, // 指定了群组关键资产别名，最多查询到一条满足条件的群组关键资产。
        {.tag = ASSET_TAG_RETURN_TYPE, .value.u32 = ASSET_RETURN_ALL}, // 此处表示需要返回群组关键资产的所有信息，即属性+明文。
        {.tag = ASSET_TAG_GROUP_ID, .value.blob = group_id},
    };

    Asset_ResultSet resultSet = {0};
    int32_t queryResult = OH_Asset_Query(attr, sizeof(attr) / sizeof(attr[0]), &resultSet);
    if (queryResult == ASSET_SUCCESS) {
        // 解析resultSet。
        for (uint32_t i = 0; i < resultSet.count; i++) {
            // 解析secret属性：其中data数据对应是secret->blob.data，长度对应是secret->blob.size。
            Asset_Attr *secret = OH_Asset_ParseAttr(resultSet.results + i, ASSET_TAG_SECRET);
        }
    }
    OH_Asset_FreeResultSet(&resultSet);
    
    napi_value ret;
    napi_create_int32(env, queryResult, &ret);
    return ret;
}
```

## 查询单条群组关键资产属性

查询别名是demo_alias的关键资产属性。

```c
#include <string.h>

#include "asset/asset_api.h"

static napi_value QueryAttributes(napi_env env, napi_callback_info info)
{
    static const char *ALIAS = "demo_alias";
    static const char *GROUP_ID = "demo_group_id";
    Asset_Blob alias = {(uint32_t)(strlen(ALIAS)), (uint8_t *)ALIAS};
    Asset_Blob group_id = {(uint32_t)(strlen(GROUP_ID)), (uint8_t *)GROUP_ID};
    Asset_Attr attr[] = {
        {.tag = ASSET_TAG_ALIAS, .value.blob = alias}, // 指定了群组关键资产别名，最多查询到一条满足条件的群组关键资产。
        {.tag = ASSET_TAG_RETURN_TYPE, .value.u32 = ASSET_RETURN_ATTRIBUTES}, // 此处表示仅返回群组关键资产属性，不包含群组关键资产明文。
        {.tag = ASSET_TAG_GROUP_ID, .value.blob = group_id},
    };

    Asset_ResultSet resultSet = {0};
    int32_t queryResult = OH_Asset_Query(attr, sizeof(attr) / sizeof(attr[0]), &resultSet);
    if (queryResult == ASSET_SUCCESS) {
        // 解析结果。
        for (uint32_t i = 0; i < resultSet.count; i++) {
            // 解析数据标签：其中数据是label->blob.data，长度对应是label->blob.size。
            Asset_Attr *label = OH_Asset_ParseAttr(resultSet.results + i, ASSET_TAG_DATA_LABEL_NORMAL_1);
        }
    }
    OH_Asset_FreeResultSet(&resultSet);
    
    napi_value ret;
    napi_create_int32(env, queryResult, &ret);
    return ret;
}
```