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Add-ons
  1. MDN
  2. Mozilla
  3. Add-ons
  4. Browser extensions
  5. JavaScript APIs
  6. downloads

downloads

In This Article
  1. Types
  2. Functions
  3. Events
  4. Browser compatibility
    1. Chrome incompatibilities
  5. Example extensions

Enables extensions to interact with the browser's download manager. You can use this API module to download files, cancel, pause, resume downloads, and show downloaded files in the file manager.

To use this API you need to have the "downloads" API permission specified in your manifest.json file.

Types

downloads.FilenameConflictAction
Defines options for what to do if the name of a downloaded file conflicts with an existing file.
downloads.InterruptReason
Defines a set of possible reasons why a download was interrupted.
downloads.DangerType
Defines a set of common warnings of possible dangers associated with downloadable files.
downloads.State
Defines different states that a current download can be in.
downloads.DownloadItem
Represents a downloaded file.
downloads.StringDelta
Represents the difference between two strings.
downloads.DoubleDelta
Represents the difference between two doubles.
downloads.BooleanDelta
Represents the difference between two booleans.
downloads.DownloadTime
Represents the time a download took to complete.
downloads.DownloadQuery
Defines a set of parameters that can be used to search the downloads manager for a specific set of downloads.

Functions

downloads.download()
Downloads a file, given its URL and other optional preferences.
downloads.search()
Queries the DownloadItems available in the browser's downloads manager, and returns those that match the specified search criteria.
downloads.pause()
Pauses a download.
downloads.resume()
Resumes a paused download.
downloads.cancel()
Cancels a download.
downloads.getFileIcon()
Retrieves an icon for the specified download.
downloads.open()
Opens the downloaded file with its associated application.
downloads.show()
Opens the platform's file manager application to show the downloaded file in its containing folder.
downloads.showDefaultFolder()
Opens the platform's file manager application to show the default downloads folder.
downloads.erase()
Erases matching DownloadItems from the browser's download history, without deleting the downloaded files from disk.
downloads.removeFile()
Removes a downloaded file from disk, but not from the browser's download history.
downloads.acceptDanger()
Prompts the user to accept or cancel a dangerous download.
downloads.drag()
Initiates dragging the downloaded file to another application.
downloads.setShelfEnabled()
Enables or disables the gray shelf at the bottom of every window associated with the current browser profile. The shelf will be disabled as long as at least one extension has disabled it.

Events

downloads.onCreated
Fires with the DownloadItem object when a download begins.
downloads.onErased
Fires with the downloadId when a download is erased from history.
downloads.onChanged
When any of a DownloadItem's properties except bytesReceived changes, this event fires with the downloadId and an object containing the properties that changed.

Browser compatibility

ChromeEdgeFirefoxFirefox for AndroidOpera
BooleanDeltaYesNo4748Yes
DangerTypeYesNo4748Yes
DoubleDeltaYesNo4748Yes
DownloadItemYesNo4748Yes
DownloadQueryYesNo4748Yes
DownloadTimeYesNo4748Yes
FilenameConflictActionYesNo47 *48 *Yes
InterruptReasonYesNo4748Yes
StateYesNo4748Yes
StringDeltaYesNo4748Yes
acceptDangerYesNoNoNoYes
cancelYesNo4848Yes
downloadYesNo47 *48 *Yes
dragYesNoNoNoYes
eraseYesNo4848Yes
getFileIconYesNoNoNoYes
onChangedYesNo4748Yes
onCreatedYesNo4848Yes
onErasedYesNo4848Yes
openYesNo4848Yes
pauseYesNo4848Yes
removeFileYesNo4848Yes
resumeYesNo4848Yes
searchYesNo4748Yes
setShelfEnabledYesNoNoNoYes
showYesNo4848Yes
showDefaultFolderYesNo4848Yes

The "Chrome incompatibilities" section is included from https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Chrome_incompatibilities using the WebExtChromeCompat macro.

If you need to update this content, edit https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Chrome_incompatibilities, then shift-refresh this page to see your changes.

Chrome incompatibilities

None.

Example extensions

  • latest-download

Acknowledgements

This API is based on Chromium's chrome.downloads API.

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

// Copyright 2015 The Chromium Authors. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//    * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//    * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//    * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Document Tags and Contributors

Tags: 
  • Add-ons
  • API
  • downloads
  • Extensions
  • Interface
  • Non-standard
  • Reference
  • WebExtensions
 Contributors to this page: andrewtruongmoz, wbamberg, chrisdavidmills
 Last updated by: andrewtruongmoz, Jul 13, 2017, 10:14:01 AM
See also
  1. Browser extensions
  2. Getting started
    1. What are extensions?
    2. Your first extension
    3. Your second extension
    4. Anatomy of an extension
    5. Example extensions
  3. How to
    1. Intercept HTTP requests
    2. Modify a web page
    3. Add a button to the toolbar
    4. Implement a settings page
  4. User interface
    1. Introduction
    2. Toolbar button
    3. Address bar button
    4. Sidebar
    5. Context menu items
    6. Options page
    7. Bundled web pages
    8. Notifications
    9. Address bar suggestions
    10. Developer tools panels
  5. Concepts
    1. Using the JavaScript APIs
    2. Content scripts
    3. Match patterns
    4. Internationalization
    5. Content Security Policy
    6. Native messaging
  6. Porting
    1. Porting a Google Chrome extension
    2. Porting a legacy Firefox extension
    3. Embedded WebExtensions
    4. Comparison with the Add-on SDK
    5. Comparison with XUL/XPCOM extensions
    6. Chrome incompatibilities
    7. Differences between desktop and Android
  7. Firefox workflow
    1. Temporary Installation in Firefox
    2. Debugging
    3. Developing for Firefox for Android
    4. Getting started with web-ext
    5. web-ext command reference
    6. Extensions and the Add-on ID
    7. Publishing your extension
  8. JavaScript APIs
    1. Browser support for JavaScript APIs
    2. alarms
    3. bookmarks
    4. browserAction
    5. browsingData
    6. commands
    7. contextMenus
    8. contextualIdentities
    9. cookies
    10. devtools.inspectedWindow
    11. devtools.network
    12. devtools.panels
    13. downloads
      1. Methods
        1. acceptDanger()
        2. cancel()
        3. download()
        4. drag()
        5. erase()
        6. getFileIcon()
        7. open()
        8. pause()
        9. removeFile()
        10. resume()
        11. search()
        12. setShelfEnabled()
        13. show()
        14. showDefaultFolder()
      2. Types
        1. BooleanDelta
        2. DangerType
        3. DoubleDelta
        4. DownloadItem
        5. DownloadQuery
        6. DownloadTime
        7. FilenameConflictAction
        8. InterruptReason
        9. State
        10. StringDelta
      3. Events
        1. onChanged
        2. onCreated
        3. onErased
    14. events
    15. extension
    16. extensionTypes
    17. history
    18. i18n
    19. identity
    20. idle
    21. management
    22. notifications
    23. omnibox
    24. pageAction
    25. permissions
    26. privacy
    27. proxy
    28. runtime
    29. sessions
    30. sidebarAction
    31. storage
    32. tabs
    33. topSites
    34. types
    35. webNavigation
    36. webRequest
    37. windows
  9. Manifest keys
    1. applications
    2. author
    3. background
    4. browser_action
    5. chrome_settings_overrides
    6. chrome_url_overrides
    7. commands
    8. content_scripts
    9. content_security_policy
    10. default_locale
    11. description
    12. developer
    13. devtools_page
    14. homepage_url
    15. icons
    16. incognito
    17. manifest_version
    18. name
    19. omnibox
    20. optional_permissions
    21. options_ui
    22. page_action
    23. permissions
    24. protocol_handlers
    25. short_name
    26. sidebar_action
    27. version
    28. web_accessible_resources
  10. Themes
  11. Publishing add-ons
  12. Guides
    1. Signing and distribution overview
    2. Submit an add-on
    3. Creating an appealing listing
    4. Review policies
    5. Developer agreement
    6. Featured add-ons
    7. Contact addons.mozilla.org
  13. Community and support
  14. Channels
    1. Add-ons blog
    2. Add-on forums
    3. Stack Overflow
    4. Development newsgroup
    5. IRC Channel
  15. Legacy add-ons
  16. Legacy technologies
    1. Add-on SDK
    2. Legacy Firefox for Android
    3. Bootstrapped extensions
    4. Overlay extensions