---
title: "system.perspective.download"
description: "Downloads data from the Gateway to a device running a Session."
---

# system.perspective.download

> Downloads data from the Gateway to a device running a Session.

This function is used in **Python Scripting**.

## Description
When calling from the Gateway scope, the call must include a sessionId. 

 

This function interacts with mobile apps directly to ensure that download requests can be saved to the local device. Requires version 1.0.2 of the [Ignition Perspective App](ignition-modules\perspective\perspective-sessions\ignition-perspective-app.md).

## Syntax - Gateway Scope
:::tip
This function accepts [keyword arguments](platform\scripting\python-scripting\user-defined-functions.md#keyword-arguments).
:::

`system.perspective.download(filename, data,  [contentType], sessionId, [pageId])`

### Parameters
Type | Parameter | Description 
------- | ------- | ------ 
String | `filename` | Suggested name for the downloaded file.
String | `data` | The data to be downloaded. May be a string, a byte[], or an InputStream. Strings will be written in UTF-8 encoding.
String | `contentType` | Value for the "Content-Type" header, for example: "text/plain; charset=utf-8". [optional] 
String | `sessionId` | Identifier of the Session to target. If omitted, the current Session will be used automatically. When targeting a different session, then the pageId parameter must be included in the call. 
String | `pageId` | Identifier of the page to target. If omitted, the current page will be used automatically. [optional] 

### Returns
Nothing

### Scope
Gateway, Perspective Session

:::note
This function will only work in the Gateway scope if both `sessionId` and `pageId` are supplied to the call.
:::

## Syntax - Session Scope

:::tip
This function accepts [keyword arguments](platform\scripting\python-scripting\user-defined-functions.md#keyword-arguments).
:::

`system.perspective.download(filename, data, [contentType], [sessionId], [pageId])`

### Parameters 
Type | Parameter | Description 
------- | ------- | ------
String | `filename` | Suggested name for the downloaded file.
String | `data` | The data to be downloaded. May be a string, a byte[], or an InputStream. Strings will be written in UTF-8 encoding.
String | `contentType` | Value for the "Content-Type" header, for example: "text/plain; charset=utf-8". [optional] 
String | `sessionId` | Identifier of the Session to target. If omitted, the current Session will be used automatically. When targeting a different session, then the pageId parameter must be included in the call. [optional] 
String | `pageId` | Identifier of the page to target. If omitted, the current page will be used automatically. [optional] 

### Returns
Nothing

### Scope
Perspective Session

## Code Examples

```python title="Code Snippet"

# Downloads the file "myFile.pdf" (located on the Gateway) to the user running the current Session.
 
filename = 'myFile.pdf'
data = system.file.readFileAsBytes('C:\\'+filename)
system.perspective.download(filename, data)
```