electron/docs/api/download-item.md

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## Class: DownloadItem
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> Control file downloads from remote sources.
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Process: [Main](../glossary.md#main-process)
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`DownloadItem` is an `EventEmitter` that represents a download item in Electron.
It is used in `will-download` event of `Session` class, and allows users to
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control the download item.
```javascript
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// In the main process.
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const { BrowserWindow } = require('electron')
let win = new BrowserWindow()
win.webContents.session.on('will-download', (event, item, webContents) => {
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// Set the save path, making Electron not to prompt a save dialog.
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item.setSavePath('/tmp/save.pdf')
item.on('updated', (event, state) => {
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if (state === 'interrupted') {
console.log('Download is interrupted but can be resumed')
} else if (state === 'progressing') {
if (item.isPaused()) {
console.log('Download is paused')
} else {
console.log(`Received bytes: ${item.getReceivedBytes()}`)
}
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}
})
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item.once('done', (event, state) => {
if (state === 'completed') {
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console.log('Download successfully')
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} else {
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console.log(`Download failed: ${state}`)
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}
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})
})
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```
### Instance Events
#### Event: 'updated'
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Returns:
* `event` Event
* `state` String - Can be `progressing` or `interrupted`.
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Emitted when the download has been updated and is not done.
The `state` can be one of following:
* `progressing` - The download is in-progress.
* `interrupted` - The download has interrupted and can be resumed.
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#### Event: 'done'
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Returns:
* `event` Event
* `state` String - Can be `completed`, `cancelled` or `interrupted`.
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Emitted when the download is in a terminal state. This includes a completed
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download, a cancelled download (via `downloadItem.cancel()`), and interrupted
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download that can't be resumed.
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The `state` can be one of following:
* `completed` - The download completed successfully.
* `cancelled` - The download has been cancelled.
* `interrupted` - The download has interrupted and can not resume.
### Instance Methods
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The `downloadItem` object has the following methods:
#### `downloadItem.setSavePath(path)`
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* `path` String - Set the save file path of the download item.
The API is only available in session's `will-download` callback function.
If user doesn't set the save path via the API, Electron will use the original
routine to determine the save path; this usually prompts a save dialog.
**[Deprecated](modernization/property-updates.md): use the `savePath` property instead.**
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#### `downloadItem.getSavePath()`
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Returns `String` - The save path of the download item. This will be either the path
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set via `downloadItem.setSavePath(path)` or the path selected from the shown
save dialog.
**[Deprecated](modernization/property-updates.md): use the `savePath` property instead.**
#### `downloadItem.setSaveDialogOptions(options)`
* `options` SaveDialogOptions - Set the save file dialog options. This object has the same
properties as the `options` parameter of [`dialog.showSaveDialog()`](dialog.md).
This API allows the user to set custom options for the save dialog that opens
for the download item by default.
The API is only available in session's `will-download` callback function.
#### `downloadItem.getSaveDialogOptions()`
Returns `SaveDialogOptions` - Returns the object previously set by `downloadItem.setSaveDialogOptions(options)`.
#### `downloadItem.pause()`
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Pauses the download.
#### `downloadItem.isPaused()`
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Returns `Boolean` - Whether the download is paused.
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#### `downloadItem.resume()`
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Resumes the download that has been paused.
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**Note:** To enable resumable downloads the server you are downloading from must support range requests and provide both `Last-Modified` and `ETag` header values. Otherwise `resume()` will dismiss previously received bytes and restart the download from the beginning.
#### `downloadItem.canResume()`
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Returns `Boolean` - Whether the download can resume.
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#### `downloadItem.cancel()`
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Cancels the download operation.
#### `downloadItem.getURL()`
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Returns `String` - The origin url where the item is downloaded from.
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#### `downloadItem.getMimeType()`
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Returns `String` - The files mime type.
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#### `downloadItem.hasUserGesture()`
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Returns `Boolean` - Whether the download has user gesture.
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#### `downloadItem.getFilename()`
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Returns `String` - The file name of the download item.
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**Note:** The file name is not always the same as the actual one saved in local
disk. If user changes the file name in a prompted download saving dialog, the
actual name of saved file will be different.
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#### `downloadItem.getTotalBytes()`
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Returns `Integer` - The total size in bytes of the download item.
If the size is unknown, it returns 0.
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#### `downloadItem.getReceivedBytes()`
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Returns `Integer` - The received bytes of the download item.
#### `downloadItem.getContentDisposition()`
Returns `String` - The Content-Disposition field from the response
header.
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#### `downloadItem.getState()`
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Returns `String` - The current state. Can be `progressing`, `completed`, `cancelled` or `interrupted`.
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**Note:** The following methods are useful specifically to resume a
`cancelled` item when session is restarted.
#### `downloadItem.getURLChain()`
Returns `String[]` - The complete url chain of the item including any redirects.
#### `downloadItem.getLastModifiedTime()`
Returns `String` - Last-Modified header value.
#### `downloadItem.getETag()`
Returns `String` - ETag header value.
#### `downloadItem.getStartTime()`
Returns `Double` - Number of seconds since the UNIX epoch when the download was
started.
### Instance Properties
#### `downloadItem.savePath`
A `String` property that determines the save file path of the download item.
The property is only available in session's `will-download` callback function.
If user doesn't set the save path via the property, Electron will use the original
routine to determine the save path; this usually prompts a save dialog.