# @ohos.request (Upload and Download)

The **request** module provides applications with basic upload, download, and background transmission agent capabilities.

> **NOTE**
>
> The initial APIs of this module are supported since API version 6. Newly added APIs will be marked with a superscript to indicate their earliest API version.


## Modules to Import


```js
import request from '@ohos.request';
```


## Constraints

Only HTTP requests are supported. HTTPS requests are not supported.

The download server must support the HTTP HEAD method so that the size of the data to download can be obtained through **Content-length**. Otherwise, the download task fails. If this is the case, you can check the failure cause through [on('fail')<sup>7+</sup>](#onfail7).

## Constants

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

### Network Types
You can set **networkType** in [DownloadConfig](#downloadconfig) to specify the network type for the download service.

| Name| Type| Value| Description|
| -------- | -------- | -------- | -------- |
| NETWORK_MOBILE | number | 0x00000001 | Whether download is allowed on a mobile network.|
| NETWORK_WIFI | number | 0x00010000 | Whether download is allowed on a WLAN.|

### Download Error Codes
The table below lists the error codes that may be returned by [on('fail')<sup>7+</sup>](#onfail7)/[off('fail')<sup>7+</sup>](#offfail7)/[getTaskInfo<sup>9+</sup>](#gettaskinfo9).

| Name| Type| Value| Description|
| -------- | -------- | -------- | -------- |
| ERROR_CANNOT_RESUME<sup>7+</sup> | number |   0   | Failure to resume the download due to network errors.|
| ERROR_DEVICE_NOT_FOUND<sup>7+</sup> | number |   1   | Failure to find a storage device such as a memory card.|
| ERROR_FILE_ALREADY_EXISTS<sup>7+</sup> | number |   2   | Failure to download the file because it already exists.|
| ERROR_FILE_ERROR<sup>7+</sup> | number |   3   | File operation failure.|
| ERROR_HTTP_DATA_ERROR<sup>7+</sup> | number |   4   | HTTP transmission failure.|
| ERROR_INSUFFICIENT_SPACE<sup>7+</sup> | number |   5   | Insufficient storage space.|
| ERROR_TOO_MANY_REDIRECTS<sup>7+</sup> | number |   6   | Error caused by too many network redirections.|
| ERROR_UNHANDLED_HTTP_CODE<sup>7+</sup> | number |   7   | Unidentified HTTP code.|
| ERROR_UNKNOWN<sup>7+</sup> | number |   8   | Unknown error.|
| ERROR_OFFLINE<sup>9+</sup> | number |   9   | No network connection.|
| ERROR_UNSUPPORTED_NETWORK_TYPE<sup>9+</sup> | number |   10   | Network type mismatch.|


### Causes of Download Pause
The table below lists the causes of download pause that may be returned by [getTaskInfo<sup>9+</sup>](#gettaskinfo9).

| Name| Type| Value| Description|
| -------- | -------- | -------- | -------- |
| PAUSED_QUEUED_FOR_WIFI<sup>7+</sup> | number |   0   | Download paused and queuing for a WLAN connection, because the file size exceeds the maximum value allowed by a mobile network session.|
| PAUSED_WAITING_FOR_NETWORK<sup>7+</sup> | number |   1   | Download paused due to a network connection problem, for example, network disconnection.|
| PAUSED_WAITING_TO_RETRY<sup>7+</sup> | number |   2   | Download paused and then retried.|
| PAUSED_BY_USER<sup>9+</sup> | number |   3   | The user paused the session.|
| PAUSED_UNKNOWN<sup>7+</sup> | number |   4   | Download paused due to unknown reasons.|

### Download Task Status Codes
The table below lists the download task status codes that may be returned by [getTaskInfo<sup>9+</sup>](#gettaskinfo9).

| Name| Type| Value| Description|
| -------- | -------- | -------- | -------- |
| SESSION_SUCCESSFUL<sup>7+</sup> | number |   0   | Successful download.|
| SESSION_RUNNING<sup>7+</sup> | number |   1   | Download in progress.|
| SESSION_PENDING<sup>7+</sup> | number |   2   | Download pending.|
| SESSION_PAUSED<sup>7+</sup> | number |   3   | Download paused.|
| SESSION_FAILED<sup>7+</sup> | number |   4   | Download failure without retry.|


## request.uploadFile<sup>9+</sup>

uploadFile(context: BaseContext, config: UploadConfig): Promise&lt;UploadTask&gt;

Uploads files. This API uses a promise to return the result. You can use [on('complete'|'fail')<sup>9+</sup>](#oncomplete--fail9) to obtain the upload error information.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context | [BaseContext](js-apis-inner-application-baseContext.md) | Yes| Application-based context.|
| config | [UploadConfig](#uploadconfig) | Yes| Upload configurations.|


**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;[UploadTask](#uploadtask)&gt; | Promise used to return the **UploadTask** object.|

**Error codes**
For details about the error codes, see [Upload and Download Error Codes](../errorcodes/errorcode-request.md).

| ID| Error Message|
| -------- | -------- |
| 13400002 | Bad file path. |

**Example**

  ```js
  let uploadTask;
  let uploadConfig = {
    url: 'https://patch',
    header: { key1: "value1", key2: "value2" },
    method: "POST",
    files: [{ filename: "test", name: "test", uri: "internal://cache/test.jpg", type: "jpg" }],
    data: [{ name: "name123", value: "123" }],
  };
  try {
    request.uploadFile(globalThis.abilityContext, uploadConfig).then((data) => {
      uploadTask = data;
    }).catch((err) => {
        console.error('Failed to request the upload. Cause: ' + JSON.stringify(err));
    });
  } catch (err) {
    console.error('err.code : ' + err.code + ', err.message : ' + err.message);
  }
  ```


## request.uploadFile<sup>9+</sup>

uploadFile(context: BaseContext, config: UploadConfig, callback: AsyncCallback&lt;UploadTask&gt;): void

Uploads files. This API uses an asynchronous callback to return the result. You can use [on('complete'|'fail')<sup>9+</sup>](#oncomplete--fail9) to obtain the upload error information.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context | [BaseContext](js-apis-inner-application-baseContext.md) | Yes| Application-based context.|
| config | [UploadConfig](#uploadconfig) | Yes| Upload configurations.|
| callback | AsyncCallback&lt;[UploadTask](#uploadtask)&gt; | Yes| Callback used to return the **UploadTask** object.|

**Error codes**
For details about the error codes, see [Upload and Download Error Codes](../errorcodes/errorcode-request.md).

| ID| Error Message|
| -------- | -------- |
| 13400002 | Bad file path. |

**Example**

  ```js
  let uploadTask;
  let uploadConfig = {
    url: 'https://patch',
    header: { key1: "value1", key2: "value2" },
    method: "POST",
    files: [{ filename: "test", name: "test", uri: "internal://cache/test.jpg", type: "jpg" }],
    data: [{ name: "name123", value: "123" }],
  };
  try {
    request.uploadFile(globalThis.abilityContext, uploadConfig, (err, data) => {
      if (err) {
          console.error('Failed to request the upload. Cause: ' + JSON.stringify(err));
          return;
      }
      uploadTask = data;
    });
  } catch (err) {
    console.error('err.code : ' + err.code + ', err.message : ' + err.message);
  }
  ```

## request.upload<sup>(deprecated)</sup>

upload(config: UploadConfig): Promise&lt;UploadTask&gt;

Uploads files. This API uses a promise to return the result.

**Model restriction**: This API can be used only in the FA model.

>  **NOTE**
>
>  This API is deprecated since API version 9. You are advised to use [request.uploadFile<sup>9+</sup>](#requestuploadfile9).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| config | [UploadConfig](#uploadconfig) | Yes| Upload configurations.|

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;[UploadTask](#uploadtask)&gt; | Promise used to return the **UploadTask** object.|

**Example**

  ```js
  let uploadTask;
  let uploadConfig = {
    url: 'https://patch',
    header: { key1: "value1", key2: "value2" },
    method: "POST",
    files: [{ filename: "test", name: "test", uri: "internal://cache/test.jpg", type: "jpg" }],
    data: [{ name: "name123", value: "123" }],
  };
  request.upload(uploadConfig).then((data) => {
      uploadTask = data;
  }).catch((err) => {
      console.error('Failed to request the upload. Cause: ' + JSON.stringify(err));
  })
  ```


## request.upload<sup>(deprecated)</sup>

upload(config: UploadConfig, callback: AsyncCallback&lt;UploadTask&gt;): void

Uploads files. This API uses an asynchronous callback to return the result.

**Model restriction**: This API can be used only in the FA model.

>  **NOTE**
>
>  This API is deprecated since API version 9. You are advised to use [request.uploadFile<sup>9+</sup>](#requestuploadfile9-1).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| config | [UploadConfig](#uploadconfig) | Yes| Upload configurations.|
| callback | AsyncCallback&lt;[UploadTask](#uploadtask)&gt; | Yes| Callback used to return the **UploadTask** object.|

**Example**

  ```js
  let uploadTask;
  let uploadConfig = {
    url: 'https://patch',
    header: { key1: "value1", key2: "value2" },
    method: "POST",
    files: [{ filename: "test", name: "test", uri: "internal://cache/test.jpg", type: "jpg" }],
    data: [{ name: "name123", value: "123" }],
  };
  request.upload(uploadConfig, (err, data) => {
      if (err) {
          console.error('Failed to request the upload. Cause: ' + JSON.stringify(err));
          return;
      }
      uploadTask = data;
  });
  ```

## UploadTask

Implements file uploads. Before using any APIs of this class, you must obtain an **UploadTask** object.



### on('progress')

on(type: 'progress', callback:(uploadedSize: number, totalSize: number) =&gt; void): void

Subscribes to an upload event. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to subscribe to. The value is **'progress'** (upload progress).|
| callback | function | Yes| Callback for the upload progress event.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| uploadedSize | number | Yes| Size of the uploaded files, in bits. |
| totalSize | number | Yes| Total size of the files to upload, in bits. |

**Example**

  ```js
  uploadTask.on('progress', function callback(uploadedSize, totalSize) {
      console.info("upload totalSize:" + totalSize + "  uploadedSize:" + uploadedSize);
  }
  );
  ```


### on('headerReceive')<sup>7+</sup>

on(type: 'headerReceive', callback:  (header: object) =&gt; void): void

Subscribes to an upload event. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to subscribe to. The value is **'headerReceive'** (response header).|
| callback | function | Yes| Callback for the HTTP Response Header event.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| header | object | Yes| HTTP Response Header.|

**Example**

  ```js
  uploadTask.on('headerReceive', function callback(headers){   
      console.info("upOnHeader headers:" + JSON.stringify(headers));
  }
  );
  ```


### on('complete' | 'fail')<sup>9+</sup>

 on(type:'complete' | 'fail', callback: Callback&lt;Array&lt;TaskState&gt;&gt;): void;

Subscribes to an upload event. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to subscribe to. The value **'complete'** means the upload completion event, and **'fail'** means the upload failure event.|
| callback | Callback&lt;Array&lt;TaskState&gt;&gt; | Yes| Callback used to return the result.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| taskstates | Array&lt;[TaskState](#taskstate9)&gt; | Yes| Upload result.|

**Example**

  ```js
  uploadTask.on('complete', function callback(taskStates) {
    for (let i = 0; i < taskStates.length; i++ ) {
      console.info("upOnComplete taskState:" + JSON.stringify(taskStates[i]));
    }
  }
  );

  uploadTask.on('fail', function callback(taskStates) {
    for (let i = 0; i < taskStates.length; i++ ) {
      console.info("upOnFail taskState:" + JSON.stringify(taskStates[i]));
    }
  }
  );
  ```


### off('progress')

off(type:  'progress',  callback?: (uploadedSize: number, totalSize: number) =&gt;  void): void

Unsubscribes from an upload event. This API uses an asynchronous callback to return the result. 

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to unsubscribe from. The value is **'progress'** (upload progress).|
| callback | function | No| Callback for the upload progress event.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| uploadedSize | number | Yes| Size of the uploaded files, in bits. |
| totalSize | number | Yes| Total size of the files to upload, in bits. |

**Example**

  ```js
  uploadTask.off('progress', function callback(uploadedSize, totalSize) {
      console.info('uploadedSize: ' + uploadedSize, 'totalSize: ' + totalSize);
  }
  );
  ```


### off('headerReceive')<sup>7+</sup>

off(type: 'headerReceive', callback?: (header: object) =&gt; void): void

Unsubscribes from an upload event. This API uses an asynchronous callback to return the result. 

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to unsubscribe from. The value is **'headerReceive'** (response header).|
| callback | function | No| Callback for the HTTP Response Header event.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| header | object | Yes| HTTP Response Header.|

**Example**

  ```js
  uploadTask.off('headerReceive', function callback(headers) {
      console.info("upOnHeader headers:" + JSON.stringify(headers));
  }
  );
  ```

### off('complete' | 'fail')<sup>9+</sup>

 off(type:'complete' | 'fail', callback?: Callback&lt;Array&lt;TaskState&gt;&gt;): void;

Unsubscribes from an upload event. This API uses an asynchronous callback to return the result. 

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to subscribe to. The value **'complete'** means the upload completion event, and **'fail'** means the upload failure event.|
| callback | Callback&lt;Array&lt;TaskState&gt;&gt; | No| Callback used to return the result.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| taskstates | Array&lt;[TaskState](#taskstate9)&gt; | Yes| Upload result.|

**Example**

  ```js
  uploadTask.off('complete', function callback(taskStates) {
    for (let i = 0; i < taskStates.length; i++ ) {
      console.info("upOnComplete taskState:" + JSON.stringify(taskStates[i]));
    }
  }
  );

  uploadTask.off('fail', function callback(taskStates) {
    for (let i = 0; i < taskStates.length; i++ ) {
      console.info("upOnFail taskState:" + JSON.stringify(taskStates[i]));
    }
  }
  );
  ```

### delete<sup>9+</sup>
delete(): Promise&lt;boolean&gt;

Deletes this upload task. This API uses a promise to return the result. 

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;boolean&gt; | Promise used to return the task removal result. It returns **true** if the operation is successful and returns **false** otherwise.|

**Example**

  ```js
  uploadTask.delete().then((result) => {
      if (result) {
          console.info('Upload task removed successfully. ');
      } else {
          console.error('Failed to remove the upload task. ');
      }
  }).catch((err) => {
      console.error('Failed to remove the upload task. Cause: ' + JSON.stringify(err));
  });
  ```


### delete<sup>9+</sup>

delete(callback: AsyncCallback&lt;boolean&gt;): void

Deletes this upload task. This API uses an asynchronous callback to return the result. 

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;boolean&gt; | Yes| Callback used to return the result.|

**Example**

  ```js
  uploadTask.delete((err, result) => {
      if (err) {
          console.error('Failed to remove the upload task. Cause: ' + JSON.stringify(err));
          return;
      }
      if (result) {
          console.info('Upload task removed successfully.');
      } else {
          console.error('Failed to remove the upload task.');
      }
  });
  ```


### remove<sup>(deprecated)</sup>

remove(): Promise&lt;boolean&gt;

Removes this upload task. This API uses a promise to return the result. 

>  **NOTE**
>
>  This API is deprecated since API version 9. You are advised to use [delete<sup>9+</sup>](#delete9).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;boolean&gt; | Promise used to return the task removal result. It returns **true** if the operation is successful and returns **false** otherwise.|

**Example**

  ```js
  uploadTask.remove().then((result) => {
      if (result) {
          console.info('Upload task removed successfully. ');
      } else {
          console.error('Failed to remove the upload task. ');
      }
  }).catch((err) => {
      console.error('Failed to remove the upload task. Cause: ' + JSON.stringify(err));
  });
  ```


### remove<sup>(deprecated)</sup>

remove(callback: AsyncCallback&lt;boolean&gt;): void

Removes this upload task. This API uses an asynchronous callback to return the result. 

>  **NOTE**
>
>  This API is deprecated since API version 9. You are advised to use [delete<sup>9+</sup>](#delete9-1).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;boolean&gt; | Yes| Callback used to return the result.|

**Example**

  ```js
  uploadTask.remove((err, result) => {
      if (err) {
          console.error('Failed to remove the upload task. Cause: ' + JSON.stringify(err));
          return;
      }
      if (result) {
          console.info('Upload task removed successfully.');
      } else {
          console.error('Failed to remove the upload task.');
      }
  });
  ```

## UploadConfig
Describes the configuration for an upload task.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| url | string | Yes| Resource URL.|
| header | Object | Yes| HTTP or HTTPS header added to an upload request.|
| method | string | Yes| Request method, which can be **'POST'** or **'PUT'**. The default value is **'POST'**.|
| files | Array&lt;[File](#file)&gt; | Yes| List of files to upload, which is submitted through **multipart/form-data**.|
| data | Array&lt;[RequestData](#requestdata)&gt; | Yes| Form data in the request body.|

## TaskState<sup>9+</sup>
Implements a **TaskState** object, which is the callback parameter of the [on('complete' | 'fail')<sup>9+</sup>](#oncomplete--fail9) and [off('complete' | 'fail')<sup>9+</sup>](#offcomplete--fail9) APIs.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Upload

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| path | string | Yes| File path.|
| responseCode | number | Yes| Return value of an upload task.|
| message | string | Yes| Description of the upload task result.|

## File
Describes the list of files in [UploadConfig](#uploadconfig).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| filename | string | Yes| File name in the header when **multipart** is used.|
| name | string | Yes| Name of a form item when **multipart** is used. The default value is **file**.|
| uri | string | Yes| Local path for storing files.<br>Only the **internal** protocol type is supported. In the value, **internal://cache/** is mandatory. Example:<br>internal://cache/path/to/file.txt |
| type | string | Yes| Type of the file content. By default, the type is obtained based on the extension of the file name or URI.|


## RequestData
Describes the form data in [UploadConfig](#uploadconfig).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| name | string | Yes| Name of a form element.|
| value | string | Yes| Value of a form element.|

## request.downloadFile<sup>9+</sup>

downloadFile(context: BaseContext, config: DownloadConfig): Promise&lt;DownloadTask&gt;

Downloads files. This API uses a promise to return the result. You can use [on('complete'|'pause'|'remove')<sup>7+</sup>](#oncompletepauseremove7) to obtain the download task state, which can be completed, paused, or removed. You can also use [on('fail')<sup>7+</sup>](#onfail7) to obtain the task download error information.


**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context | [BaseContext](js-apis-inner-application-baseContext.md) | Yes| Application-based context.|
| config | [DownloadConfig](#downloadconfig) | Yes| Download configurations.|

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;[DownloadTask](#downloadtask)&gt; | Promise used to return the result.|

**Error codes**
For details about the error codes, see [Upload and Download Error Codes](../errorcodes/errorcode-request.md).

| ID| Error Message|
| -------- | -------- |
| 13400001 | File operation error. |
| 13400002 | Bad file path. |
| 13400003 | Task manager service error. |

**Example**

  ```js
  let downloadTask;
  try {
    request.downloadFile(globalThis.abilityContext, { url: 'https://xxxx/xxxx.hap' }).then((data) => {
        downloadTask = data;
    }).catch((err) => {
        console.error('Failed to request the download. Cause: ' + JSON.stringify(err));
    })
  } catch (err) {
    console.error('err.code : ' + err.code + ', err.message : ' + err.message);
  }
  ```


## request.downloadFile<sup>9+</sup>

downloadFile(context: BaseContext, config: DownloadConfig, callback: AsyncCallback&lt;DownloadTask&gt;): void;

Downloads files. This API uses an asynchronous callback to return the result. You can use [on('complete'|'pause'|'remove')<sup>7+</sup>](#oncompletepauseremove7) to obtain the download task state, which can be completed, paused, or removed. You can also use [on('fail')<sup>7+</sup>](#onfail7) to obtain the task download error information.


**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context | [BaseContext](js-apis-inner-application-baseContext.md) | Yes| Application-based context.|
| config | [DownloadConfig](#downloadconfig) | Yes| Download configurations.|
| callback | AsyncCallback&lt;[DownloadTask](#downloadtask)&gt; | Yes| Callback used to return the result.|

**Error codes**
For details about the error codes, see [Upload and Download Error Codes](../errorcodes/errorcode-request.md).

| ID| Error Message|
| -------- | -------- |
| 13400001 | File operation error. |
| 13400002 | Bad file path. |
| 13400003 | Task manager service error. |

**Example**

  ```js
  let downloadTask;
  try {
    request.downloadFile(globalThis.abilityContext, { url: 'https://xxxx/xxxxx.hap', 
    filePath: 'xxx/xxxxx.hap'}, (err, data) => {
        if (err) {
            console.error('Failed to request the download. Cause: ' + JSON.stringify(err));
            return;
        }
        downloadTask = data;
    });
  } catch (err) {
    console.error('err.code : ' + err.code + ', err.message : ' + err.message);
  }
  ```

## request.download<sup>(deprecated)</sup>

download(config: DownloadConfig): Promise&lt;DownloadTask&gt;

Downloads files. This API uses a promise to return the result.

>  **NOTE**
>
>  This API is deprecated since API version 9. You are advised to use [request.downloadFile<sup>9+</sup>](#requestdownloadfile9).

**Model restriction**: This API can be used only in the FA model.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| config | [DownloadConfig](#downloadconfig) | Yes| Download configurations.|

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;[DownloadTask](#downloadtask)&gt; | Promise used to return the result.|

**Example**

  ```js
  let downloadTask;
  request.download({ url: 'https://xxxx/xxxx.hap' }).then((data) => {
      downloadTask = data;
  }).catch((err) => {
      console.error('Failed to request the download. Cause: ' + JSON.stringify(err));
  })
  ```


## request.download<sup>(deprecated)</sup>

download(config: DownloadConfig, callback: AsyncCallback&lt;DownloadTask&gt;): void

Downloads files. This API uses an asynchronous callback to return the result.

>  **NOTE**
>
>  This API is deprecated since API version 9. You are advised to use [request.downloadFile<sup>9+</sup>](#requestdownloadfile9-1).

**Model restriction**: This API can be used only in the FA model.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| config | [DownloadConfig](#downloadconfig) | Yes| Download configurations.|
| callback | AsyncCallback&lt;[DownloadTask](#downloadtask)&gt; | Yes| Callback used to return the result.|

**Example**

  ```js
  let downloadTask;
  request.download({ url: 'https://xxxx/xxxxx.hap', 
  filePath: 'xxx/xxxxx.hap'}, (err, data) => {
      if (err) {
          console.error('Failed to request the download. Cause: ' + JSON.stringify(err));
          return;
      }
      downloadTask = data;
  });
  ```

## DownloadTask

Implements file downloads.


### on('progress')

on(type: 'progress', callback:(receivedSize: number, totalSize: number) =&gt; void): void

Subscribes to a download event. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to subscribe to. The value is **'progress'** (download progress).|
| callback | function | Yes| Callback for the download progress event.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| receivedSize | number | Yes| Size of the downloaded files, in bits.|
| totalSize | number | Yes| Total size of the files to download, in bits.|

**Example**

  ```js
  downloadTask.on('progress', function download_callback(receivedSize, totalSize) {
      console.info("download receivedSize:" + receivedSize + " totalSize:" + totalSize);
  }
  );
  ```


### off('progress')

off(type: 'progress', callback?: (receivedSize: number, totalSize: number) =&gt; void): void

Unsubscribes from a download event. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to unsubscribe from. The value is **'progress'** (download progress).|
| callback | function | No| Callback for the download progress event.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| receivedSize | number | Yes| Size of the downloaded files, in bits.|
| totalSize | number | Yes| Total size of the files to download, in bits.|

**Example**

  ```js
  downloadTask .off('progress', function download_callback(receivedSize, totalSize) {
      console.info("download receivedSize:" + receivedSize + " totalSize:" + totalSize);
  }
  );
  ```


### on('complete'|'pause'|'remove')<sup>7+</sup>

on(type: 'complete'|'pause'|'remove', callback:() =&gt; void): void

Subscribes to a download event. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to subscribe to.<br>- **'complete'**: download task completion event.<br>- **'pause'**: download task pause event.<br>- **'remove'**: download task removal event.|
| callback | function | Yes| Callback used to return the result.|

**Example**

  ```js
  downloadTask.on('complete', function callback() {
      console.info('Download task completed.');
  }
  );
  ```


### off('complete'|'pause'|'remove')<sup>7+</sup>

off(type: 'complete'|'pause'|'remove', callback?:() =&gt; void): void

Unsubscribes from a download event. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to unsubscribe from.<br>- **'complete'**: download task completion event.<br>- **'pause'**: download task pause event.<br>- **'remove'**: download task removal event.|
| callback | function | No| Callback used to return the result.|

**Example**

  ```js
  downloadTask.off('complete', function callback() {
      console.info('Download task completed.');
  }
  );
  ```


### on('fail')<sup>7+</sup>

on(type: 'fail', callback: (err: number) =&gt; void): void

Subscribes to the download task failure event. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to subscribe to. The value is **'fail'** (download failure).|
| callback | function | Yes| Callback for the download task failure event.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| err | number | Yes| Error code of the download failure. For details about the error codes, see [Download Error Codes](#download-error-codes).|

**Example**

  ```js 
  downloadTask.on('fail', function callBack(err) {
      console.info('Download task failed. Cause:' + err);
  }
  );
  ```


### off('fail')<sup>7+</sup>

off(type: 'fail', callback?: (err: number) =&gt; void): void

Unsubscribes from the download task failure event. This API uses an asynchronous callback to return the result. 

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| type | string | Yes| Type of the event to unsubscribe from. The value is **'fail'** (download failure).|
| callback | function | No| Callback for the download task failure event.|

  Parameters of the callback function

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| err | number | Yes| Error code of the download failure. For details about the error codes, see [Download Error Codes](#download-error-codes).|

**Example**

  ```js
  downloadTask.off('fail', function callBack(err) {
      console.info('Download task failed. Cause:' + err);
  } 
  );
  ```

### delete<sup>9+</sup>

delete(): Promise&lt;boolean&gt;

Removes this download task. This API uses a promise to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;boolean&gt; | Promise used to return the task removal result.|

**Example**

  ```js
  downloadTask.delete().then((result) => {
      if (result) {
          console.info('Download task removed.');
      } else {
          console.error('Failed to remove the download task.');
      }
  }).catch ((err) => {
      console.error('Failed to remove the download task.');
  });
  ```


### delete<sup>9+</sup>

delete(callback: AsyncCallback&lt;boolean&gt;): void

Deletes this download task. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;boolean&gt; | Yes| Callback used to return the task deletion result.|

**Example**

  ```js
  downloadTask.delete((err, result)=>{
      if(err) {
          console.error('Failed to remove the download task.');
          return;
      } 
      if (result) {
          console.info('Download task removed.');
      } else {
          console.error('Failed to remove the download task.');
      } 
  });
  ```


### getTaskInfo<sup>9+</sup>

getTaskInfo(): Promise&lt;DownloadInfo&gt;

Obtains the information about this download task. This API uses a promise to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;[DownloadInfo](#downloadinfo7)&gt; | Promise used to return the download task information.|

**Example**

  ```js
  downloadTask.getTaskInfo().then((downloadInfo) => {    
      console.info('Download task queried. Data:' + JSON.stringify(downloadInfo))
  }) .catch((err) => {
      console.error('Failed to query the download task. Cause:' + err)
  });
  ```


### getTaskInfo<sup>9+</sup>

getTaskInfo(callback: AsyncCallback&lt;DownloadInfo&gt;): void

Obtains the information about this download task. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;[DownloadInfo](#downloadinfo7)&gt; | Yes| Callback used to return the download task information.|

**Example**

  ```js
  downloadTask.getTaskInfo((err, downloadInfo)=>{
      if(err) {
          console.error('Failed to query the download mimeType. Cause:' + JSON.stringify(err));
      } else {
          console.info('download query success. data:'+ JSON.stringify(downloadInfo));
      }
  });
  ```


### getTaskMimeType<sup>9+</sup>

getTaskMimeType(): Promise&lt;string&gt;

Obtains the **MimeType** of this download task. This API uses a promise to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;string&gt; | Promise used to return the **MimeType** of the download task.|

**Example**

  ```js
  downloadTask.getTaskMimeType().then((data) => {    
      console.info('Download task queried. Data:' + JSON.stringify(data));
  }).catch((err) => {
      console.error('Failed to query the download MimeType. Cause:' + JSON.stringify(err))
  });
  ```


### getTaskMimeType<sup>9+</sup>

getTaskMimeType(callback: AsyncCallback&lt;string&gt;): void;

Obtains the **MimeType** of this download task. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;string&gt; | Yes| Callback used to return the **MimeType** of the download task.|

**Example**

  ```js
  downloadTask.getTaskMimeType((err, data)=>{
      if(err) {
          console.error('Failed to query the download mimeType. Cause:' + JSON.stringify(err));
      } else {
          console.info('Download task queried. data:' + JSON.stringify(data));
      }
  });
  ```


### suspend<sup>9+</sup>

suspend(): Promise&lt;boolean&gt;

Pauses this download task. This API uses a promise to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;boolean&gt; | Promise used to return the download task pause result.|

**Example**

  ```js
  downloadTask.suspend().then((result) => {    
      if (result) {
           console.info('Download task paused. ');
      } else {
          console.error('Failed to pause the download task. Cause:' + JSON.stringify(result));
      }
  }).catch((err) => {
      console.error('Failed to pause the download task. Cause:' + JSON.stringify(err));
  });
  ```


### suspend<sup>9+</sup>

suspend(callback: AsyncCallback&lt;boolean&gt;): void

Pauses this download task. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;boolean&gt; | Yes| Callback used to return the result.|

**Example**

  ```js
  downloadTask.suspend((err, result)=>{
      if(err) {
          console.error('Failed to pause the download task. Cause:' + JSON.stringify(err));
          return;
      }
      if (result) {
           console.info('Download task paused. ');
      } else {
          console.error('Failed to pause the download task. Cause:' + JSON.stringify(result));
      }
  });
  ```


### restore<sup>9+</sup>

restore(): Promise&lt;boolean&gt;

Resumes this download task. This API uses a promise to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;boolean&gt; | Promise used to return the result.|

**Example**

  ```js
  downloadTask.restore().then((result) => {
      if (result) {
          console.info('Download task resumed.')
      } else {
          console.error('Failed to resume the download task. ');
      }
      console.info('Download task resumed.')
  }).catch((err) => {
      console.error('Failed to resume the download task. Cause:' + err);
  });
  ```


### restore<sup>9+</sup>

restore(callback: AsyncCallback&lt;boolean&gt;): void

Resumes this download task. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;boolean&gt; | Yes| Callback used to return the result.|

**Example**

  ```js
  downloadTask.restore((err, result)=>{
      if (err) {
          console.error('Failed to resume the download task. Cause:' + err);
          return;
      } 
      if (result) {
          console.info('Download task resumed.');
      } else {
          console.error('Failed to resume the download task.');
      }
  });
  ```



### remove<sup>(deprecated)</sup>

remove(): Promise&lt;boolean&gt;

Removes this download task. This API uses a promise to return the result.

>  **NOTE**
>
>  This API is deprecated since API version 9. You are advised to use [delete<sup>9+</sup>](#delete9-2).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;boolean&gt; | Promise used to return the task removal result.|

**Example**

  ```js
  downloadTask.remove().then((result) => {
      if (result) {
          console.info('Download task removed.');
      } else {
          console.error('Failed to remove the download task.');
      }
  }).catch ((err) => {
      console.error('Failed to remove the download task.');
  });
  ```


### remove<sup>(deprecated)</sup>

remove(callback: AsyncCallback&lt;boolean&gt;): void

Removes this download task. This API uses an asynchronous callback to return the result.

>  **NOTE**
>
>  This API is deprecated since API version 9. You are advised to use [delete<sup>9+</sup>](#delete9-3).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;boolean&gt; | Yes| Callback used to return the task removal result.|

**Example**

  ```js
  downloadTask.remove((err, result)=>{
      if(err) {
          console.error('Failed to remove the download task.');
          return;
      } 
      if (result) {
          console.info('Download task removed.');
      } else {
          console.error('Failed to remove the download task.');
      } 
  });
  ```


### query<sup>(deprecated)</sup>

query(): Promise&lt;DownloadInfo&gt;

Queries this download task. This API uses a promise to return the result.

>  **NOTE**
>
>  This API is supported since API version 7 and is deprecated since API version 9. You are advised to use [getTaskInfo<sup>9+</sup>](#gettaskinfo9).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;[DownloadInfo](#downloadinfo7)&gt; | Promise used to return the download task information.|

**Example**

  ```js
  downloadTask.query().then((downloadInfo) => {    
      console.info('Download task queried. Data:' + JSON.stringify(downloadInfo))
  }) .catch((err) => {
      console.error('Failed to query the download task. Cause:' + err)
  });
  ```


### query<sup>(deprecated)</sup>

query(callback: AsyncCallback&lt;DownloadInfo&gt;): void

Queries this download task. This API uses an asynchronous callback to return the result.

>  **NOTE**
>
>  This API is supported since API version 7 and is deprecated since API version 9. You are advised to use [getTaskInfo<sup>9+</sup>](#gettaskinfo9-1).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;[DownloadInfo](#downloadinfo7)&gt; | Yes| Callback used to return the download task information.|

**Example**

  ```js
  downloadTask.query((err, downloadInfo)=>{
      if(err) {
          console.error('Failed to query the download mimeType. Cause:' + JSON.stringify(err));
      } else {
          console.info('download query success. data:'+ JSON.stringify(downloadInfo));
      }
  });
  ```


### queryMimeType<sup>(deprecated)</sup>

queryMimeType(): Promise&lt;string&gt;

Queries the **MimeType** of this download task. This API uses a promise to return the result.

>  **NOTE**
>
>  This API is supported since API version 7 and is deprecated since API version 9. You are advised to use [getTaskMimeType<sup>9+</sup>](#gettaskmimetype9).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;string&gt; | Promise used to return the **MimeType** of the download task.|

**Example**

  ```js
  downloadTask.queryMimeType().then((data) => {    
      console.info('Download task queried. Data:' + JSON.stringify(data));
  }).catch((err) => {
      console.error('Failed to query the download MimeType. Cause:' + JSON.stringify(err))
  });
  ```


### queryMimeType<sup>(deprecated)</sup>

queryMimeType(callback: AsyncCallback&lt;string&gt;): void;

Queries the **MimeType** of this download task. This API uses an asynchronous callback to return the result.

>  **NOTE**
>
>  This API is supported since API version 7 and is deprecated since API version 9. You are advised to use [getTaskMimeType<sup>9+</sup>](#gettaskmimetype9-1).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;string&gt; | Yes| Callback used to return the **MimeType** of the download task.|

**Example**

  ```js
  downloadTask.queryMimeType((err, data)=>{
      if(err) {
          console.error('Failed to query the download mimeType. Cause:' + JSON.stringify(err));
      } else {
          console.info('Download task queried. data:' + JSON.stringify(data));
      }
  });
  ```


### pause<sup>(deprecated)</sup>

pause(): Promise&lt;void&gt;

Pauses this download task. This API uses a promise to return the result.

>  **NOTE**
>
>  This API is supported since API version 7 and is deprecated since API version 9. You are advised to use [suspend<sup>9+</sup>](#suspend9).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;void&gt; | Promise used to return the download task pause result.|

**Example**

  ```js
  downloadTask.pause().then((result) => {    
      if (result) {
           console.info('Download task paused. ');
      } else {
          console.error('Failed to pause the download task. Cause:' + JSON.stringify(result));
      }
  }).catch((err) => {
      console.error('Failed to pause the download task. Cause:' + JSON.stringify(err));
  });
  ```


### pause<sup>(deprecated)</sup>

pause(callback: AsyncCallback&lt;void&gt;): void

>  **NOTE**
>
>  This API is supported since API version 7 and is deprecated since API version 9. You are advised to use [suspend<sup>9+</sup>](#suspend9-1).

Pauses this download task. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;void&gt; | Yes| Callback used to return the result.|

**Example**

  ```js
  downloadTask.pause((err, result)=>{
      if(err) {
          console.error('Failed to pause the download task. Cause:' + JSON.stringify(err));
          return;
      }
      if (result) {
           console.info('Download task paused. ');
      } else {
          console.error('Failed to pause the download task. Cause:' + JSON.stringify(result));
      }
  });
  ```


### resume<sup>(deprecated)</sup>

resume(): Promise&lt;void&gt;

Resumes this download task. This API uses a promise to return the result.

>  **NOTE**
>
>  This API is supported since API version 7 and is deprecated since API version 9. You are advised to use [restore<sup>9+</sup>](#restore9).

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Return value**

| Type| Description|
| -------- | -------- |
| Promise&lt;void&gt; | Promise used to return the result.|

**Example**

  ```js
  downloadTask.resume().then((result) => {
      if (result) {
          console.info('Download task resumed.')
      } else {
          console.error('Failed to resume the download task. ');
      }
      console.info('Download task resumed.')
  }).catch((err) => {
      console.error('Failed to resume the download task. Cause:' + err);
  });
  ```


### resume<sup>(deprecated)</sup>

resume(callback: AsyncCallback&lt;void&gt;): void

>  **NOTE**
>
>  This API is supported since API version 7 and is deprecated since API version 9. You are advised to use [restore<sup>9+</sup>](#restore9-1).

Resumes this download task. This API uses an asynchronous callback to return the result.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

**Parameters**

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| callback | AsyncCallback&lt;void&gt; | Yes| Callback used to return the result.|

**Example**

  ```js
  downloadTask.resume((err, result)=>{
      if (err) {
          console.error('Failed to resume the download task. Cause:' + err);
          return;
      } 
      if (result) {
          console.info('Download task resumed.');
      } else {
          console.error('Failed to resume the download task.');
      }
  });
  ```


## DownloadConfig
Defines the download task configuration.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| url | string | Yes| Resource URL.|
| header | Object | No| HTTPS flag header to be included in the download request.<br>The **X-TLS-Version** parameter in **header** specifies the TLS version to be used. If this parameter is not set, the CURL_SSLVERSION_TLSv1_2 version is used. Available options are as follows:<br>CURL_SSLVERSION_TLSv1_0<br>CURL_SSLVERSION_TLSv1_1<br>CURL_SSLVERSION_TLSv1_2<br>CURL_SSLVERSION_TLSv1_3<br>The **X-Cipher-List** parameter in **header** specifies the cipher suite list to be used. If this parameter is not specified, the secure cipher suite list is used. Available options are as follows:<br>- The TLS 1.2 cipher suite list includes the following ciphers:<br>TLS_DHE_RSA_WITH_AES_128_GCM_SHA256,TLS_DHE_RSA_WITH_AES_256_GCM_SHA384,<br>TLS_DHE_DSS_WITH_AES_128_GCM_SHA256,TLS_DSS_RSA_WITH_AES_256_GCM_SHA384,<br>TLS_PSK_WITH_AES_256_GCM_SHA384,TLS_DHE_PSK_WITH_AES_128_GCM_SHA256,<br>TLS_DHE_PSK_WITH_AES_256_GCM_SHA384,TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256,<br>TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,<br>TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,<br>TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256,<br>TLS_ECDHE_PSK_WITH_AES_128_GCM_SHA256,TLS_ECDHE_PSK_WITH_AES_256_GCM_SHA384,<br>TLS_ECDHE_PSK_WITH_AES_128_GCM_SHA256,TLS_DHE_RSA_WITH_AES_128_CCM,<br>TLS_DHE_RSA_WITH_AES_256_CCM,TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256,<br>TLS_PSK_WITH_AES_256_CCM,TLS_DHE_PSK_WITH_AES_128_CCM,<br>TLS_DHE_PSK_WITH_AES_256_CCM,TLS_ECDHE_ECDSA_WITH_AES_128_CCM,<br>TLS_ECDHE_ECDSA_WITH_AES_256_CCM,TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256<br>- The TLS 1.3 cipher suite list includes the following ciphers:<br>TLS_AES_128_GCM_SHA256,TLS_AES_256_GCM_SHA384,TLS_CHACHA20_POLY1305_SHA256,TLS_AES_128_CCM_SHA256<br>- The TLS 1.3 cipher suite list adds the Chinese national cryptographic algorithm:<br>TLS_SM4_GCM_SM3,TLS_SM4_CCM_SM3 |
| enableMetered | boolean | No| Whether download is allowed on a metered connection.<br>- **true**: allowed<br>- **false**: not allowed|
| enableRoaming | boolean | No| Whether download is allowed on a roaming network.<br>- **true**: allowed<br>- **false**: not allowed|
| description | string | No| Description of the download session.|
| filePath<sup>7+</sup> | string | No| Path where the downloaded file is stored.<br>- filePath:'/data/storage/el2/base/haps/entry/files/test.txt': Save the file to an absolute path.<br>- In the FA model, use [context](js-apis-inner-app-context.md#contextgetcachedir) to obtain the cache directory of the application, for example, **\${featureAbility.getContext().getFilesDir()}/test.txt\**, and store the file in this directory.<br>- In the stage model, use [AbilityContext](js-apis-inner-application-context.md) to obtain the file path, for example, **\${globalThis.abilityContext.tempDir}/test.txt\**, and store the file in this path.|
| networkType | number | No| Network type allowed for download.<br>- NETWORK_MOBILE: 0x00000001<br>- NETWORK_WIFI: 0x00010000|
| title | string | No| Download task name.|
| background<sup>9+</sup> | boolean | No| Whether to enable the background task notification. When this parameter is enabled, the download status is displayed in the notification panel.|


## DownloadInfo<sup>7+</sup>
Defines the download task information, which is the callback parameter of the [query<sup>(deprecated)</sup>](#querydeprecated-1) API.

**Required permissions**: ohos.permission.INTERNET

**System capability**: SystemCapability.MiscServices.Download

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| downloadId | number | Yes| ID of the downloaded file.|
| failedReason | number | No| Cause of the download failure. The value can be any constant in [Download Error Codes](#download-error-codes).|
| fileName | string | Yes| Name of the downloaded file.|
| filePath | string | Yes| URI of the saved file.|
| pausedReason | number | No| Cause of download pause. The value can be any constant in [Causes of Download Pause](#causes-of-download-pause).|
| status | number | Yes| Download task status code. The value can be any constant in [Download Task Status Codes](#download-task-status-codes).|
| targetURI | string | Yes| URI of the downloaded file.|
| downloadTitle | string | Yes| Download task name.|
| downloadTotalBytes | number | Yes| Total size of the files to download, in bytes.|
| description | string | Yes| Description of the file to download.|
| downloadedBytes | number | Yes| Size of the files downloaded, in bytes.|