# File Subsystem Changelog

## cl.file.1 Change of the mediaLibrary Interface Compatibility

Changed the compatibility of some **mediaLibrary** APIs.

**Change Impact**

The compatibility of some [mediaLibrary](../../../application-dev/reference/apis/js-apis-medialibrary.md) APIs is changed.
For applications developed based on earlier versions, pay attention to the iterative update of deprecated APIs.

**Key API/Component Changes**

| Module                   | Method/Attribute/Enum/Constant                                         | Change Type|
| ------------------------- | ------------------------------------------------------------ | -------- |
| medialibrary   |  **function** getFileAssets(options: MediaFetchOptions, callback: AsyncCallback<FetchFileResult>): void | Interface compatibility changed    |
| medialibrary   |  **function** getFileAssets(options: MediaFetchOptions): Promise<FetchFileResult> | Interface compatibility changed    |
| medialibrary   |  **function** createAsset(mediaType: MediaType, displayName: string, relativePath: string, callback: AsyncCallback<FileAsset>): void| Interface compatibility changed    |
| medialibrary   |  **function** createAsset(mediaType: MediaType, displayName: string, relativePath: string): Promise<FileAsset>| Interface compatibility changed    |
| medialibrary   |  **function** getAlbums(options: MediaFetchOptions, callback: AsyncCallback<Array<Album>>): void | Interface compatibility changed    |
| medialibrary   |  **function** getAlbums(options: MediaFetchOptions): Promise<Array<Album>> | Interface compatibility changed    |
| medialibrary   |  **function** FileAsset.commitModify(callback: AsyncCallback<void>): void | Interface compatibility changed    |
| medialibrary   |  **function** FileAsset.commitModify(): Promise<void> | Interface compatibility changed    |
| medialibrary   |  **function** FileAsset.deleteAsset(uri: string, callback: AsyncCallback<void>): void | Interface compatibility changed    |
| medialibrary   |  **function** FileAsset.deleteAsset(uri: string): Promise<void> | Interface compatibility changed    |

**Adaptation Guide**

**getFileAssets**

From API version 10, the albums represented by physical directories are replaced by logical albums, which allow multiple files in an album and presence of a file in multiple albums. This design, however, makes **parent**, **albumId**, **albumUri**, and **albumName** incompatible. They cannot be used as parameters of **MediaFetchOptions** in **getFileAssets()**. The following is an example of incorrect use of the APIs.

1. Call [getMediaLibrary](../../../application-dev/reference/apis/js-apis-medialibrary.md#medialibrarygetmedialibrary) to obtain a **MediaLibrary** instance.
2. Call [MediaFetchOptions](../../../application-dev/reference/apis/js-apis-medialibrary.md#mediafetchoptions7) to create the file fetching options.
3. Call [getFileAssets](../../../application-dev/reference/apis/js-apis-medialibrary.md#getfileassets7) to obtain file assets.

**Example (incorrect)**:

```js
import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let fileKeyObj = mediaLibrary.FileKey;
    let albumId = 1;
    let getImageOp = {
      selections: fileKeyObj.ALBUM_ID + '= ?', // File assets cannot be obtained based on the parent, albumId, albumUri, and albumName attributes.
      selectionArgs: [albumId.toString()],
    };
    const fetchFileResult = await media.getFileAssets(getImageOp); // The obtained fetchFileResult is empty.
    const fileAsset = await fetchFileResult.getFirstObject();
    console.info('mediaLibrary fileAsset displayName: ' + fileAsset.displayName);
  } catch (err) {
    console.error('mediaLibrary fail, err: ' + err);
  }
}
```

Use **getFileAssets()** as follows:

**Example (correct)**:

```js
import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let fileKeyObj = mediaLibrary.FileKey;
    let imageType = mediaLibrary.MediaType.IMAGE;
    let getImageOp = {
      selections: fileKeyObj.MEDIA_TYPE + '= ?',
      selectionArgs: [imageType.toString()], // Query all files of the image type.
    };
    const fetchFileResult = await media.getFileAssets(getImageOp); 
    const fileAsset = await fetchFileResult.getFirstObject();
    console.info('mediaLibrary fileAsset displayName: ' + fileAsset.displayName);
  } catch (err) {
    console.error('mediaLibrary fail, err: ' + err);
  }
}
```

**createAsset**

Since the SDK of API version 10, **relativePath** is no longer associated with an album. After a file is created, the last-level directory of **relativePath** is not displayed as an album.

**getAlbums**

Since the SDK of API version 10, **relativePath** is no longer associated with an album. Therefore, **relativePath** cannot be used as a search criterion in **getAlbums**, and the values of **ALBUM_NAME** can be **Camera** and **Screenshots** only. The following is an example of incorrect use of the APIs.

1. Use [getMediaLibrary](../../../application-dev/reference/apis/js-apis-medialibrary.md#medialibrarygetmedialibrary) to obtain a **MediaLibrary** instance.
2. Use [MediaFetchOptions](../../../application-dev/reference/apis/js-apis-medialibrary.md#mediafetchoptions7) to create the album fetching options.
3. Use [getAlbums](../../../application-dev/reference/apis/js-apis-medialibrary.md#getalbums7) to obtain albums.

**Example (incorrect)**:

```js
import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let AlbumNoArgsfetchOp = {
      selections: mediaLibrary.FileKey.ALBUM_NAME + ' = ?',
      selectionArgs:['New album 1'], //Obtain the album named New album 1.
    };
    const albumList = await media.getAlbums(AlbumNoArgsfetchOp); // The fetchFileResult returned is empty.
    for (let i = 0; i < albumList.length; i++) {
      console.info('mediaLibrary album albumName: ' + albumList[i].albumName);
    }
  } catch (err) {
    console.error('mediaLibrary fail, err: ' + err);
  }
}
```

The following example shows how to obtain **Camera** and **Screenshots** albums:

**Example (correct)**:

```js
import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let AlbumNoArgsfetchOp = {
      selections: mediaLibrary.FileKey.ALBUM_NAME + ' = ? OR ' + mediaLibrary.FileKey.ALBUM_NAME + ' = ?',
      selectionArgs: ['Camera', 'Screenshots'], // Obtain the camera and screenshot albums.
    };
    const albumList = await media.getAlbums(AlbumNoArgsfetchOp);
    for (let i = 0; i < albumList.length; i++) {
      console.info('mediaLibrary album albumName: ' + albumList[i].albumName);
    }
  } catch (err) {
    console.error('mediaLibrary fail, err: ' + err);
  }
}
```

**FileAsset.commitModify**

The **orientation** attribute for audio is deleted from the SDK of API version 10. When **commitModify** is used, the **orientation** attribute of audio resources cannot be modified.

**FileAsset.deleteAsset**

The change has resolved a known issue of the file deletion mechanism. This issue may cause a system application to permanently delete a file that is not in the trash using **MediaLibrary.deleteAsset**.

The correct procedure for a system application to permanently delete a file is as follows:

1. Call [getFileAssets](../../../application-dev/reference/apis/js-apis-medialibrary.md#getfileassets7) to obtain file assets.
2. Call [FileAsset.trash](../../../application-dev/reference/apis/js-apis-medialibrary.md#trash8) to move the file to the trash.
3. Call [MediaLibrary.deleteAsset](../../../application-dev/reference/apis/js-apis-medialibrary.md#deleteasset8) to permanently delete the file.

**Example (correct)**:

```js
import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let fileKeyObj = mediaLibrary.FileKey;
    let imageType = mediaLibrary.MediaType.IMAGE;
    let getImageOp = {
      selections: fileKeyObj.MEDIA_TYPE + '= ?',
      selectionArgs: [imageType.toString()],
    };
    const fetchFileResult = await media.getFileAssets(getImageOp); 
    const fileAsset = await fetchFileResult.getFirstObject();
    // Delete the file (move it to the trash of Gallery).
    await fileAsset.trash(true);
    // Delete the file from the system permanently.
    await media.deleteAsset(fileAsset.uri);
  } catch (err) {
    console.error('Failed to delete asset permanently from system, error: ' + err);
  }
}
```