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  2. Mozilla
  3. Add-ons
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  5. JavaScript APIs
  6. downloads
  7. downloads.DownloadItem

downloads.DownloadItem

In This Article
  1. Type
  2. Browser compatibility

The DownloadItem type of the downloads API represents a downloaded file.

Type

Values of this type are objects. They contain the following properties:

id
An integer representing a unique identifier for the downloaded file that is persistent across browser sessions.
url
A string representing the absolute URL from which the file was downloaded.
referrer
A string representing the downloaded file's referrer.
filename
A string representing the file's absolute local path.
incognito
A boolean that indicates whether the download is recorded in the browser's history (false), or not (true).
danger
A string indicating whether this download is thought to be safe or known to be suspicious. Its possible values are defined in the downloads.DangerType type.
mime
A string representing the downloaded file's MIME type.
startTime
A string (in ISO 8601 format) representing the number of milliseconds between the UNIX epoch and when this download began.
endTimeOptional
A string (in ISO 8601 format) representing the number of milliseconds between the UNIX epoch and when this download ended.
estimatedEndTimeOptional
A string (in ISO 8601 format) representing the estimated number of milliseconds between the UNIX epoch and when this download is estimated to be completed.
state
A string Indicating whether the download is progressing, interrupted, or complete. Possible values are defined in the downloads.State type.
paused
A boolean indicating whether the download is paused, i.e. if the download has stopped reading data from the host but has kept the connection open. If so, the value is true, false if not.
canResume
A boolean indicating whether a currently-interrupted (e.g. paused) download can be resumed from the point where it was interrupted (true), or not (false).
errorOptional
A string indicating why a download was interrupted. Possible values are defined in the downloads.InterruptReason type.
bytesReceived
A number representing the number of bytes received so far from the host during the download; this does not take file compression into consideration.
totalBytes
A number indicating the total number of bytes in the file being downloaded. This does not take file compression into consideration. A value of -1 here means that the total number of bytes is unknown.
fileSize
A number indicating the total number of bytes in the whole file, after decompression. A value of -1 here means that the total file size is unknown.
exists
A boolean indicating whether a downloaded file still exists (true) or not (false). This information might be out-of-date, as browsers do not automatically watch for file removal — to check whether a file exists, call the downloads.search() method, filtering for the file in question.
byExtensionIdOptional
A string representing the ID of the extension that triggered the download (if it was triggered by an extension). This does not change once set.
byExtensionNameOptional
A string representing the name of the extension that triggered the download (if it was triggered by an extension). This may change if the extension changes its name or the user changes their locale.

Browser compatibility

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

ChromeEdgeFirefoxFirefox for AndroidOpera
Basic supportYesNo4748Yes

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,
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Document Tags and Contributors

Tags: 
  • Add-ons
  • API
  • DownloadItem
  • downloads
  • Extensions
  • Non-standard
  • Reference
  • Type
  • WebExtensions
 Contributors to this page: andrewtruongmoz, JeffersonScher, wbamberg, chrisdavidmills
 Last updated by: andrewtruongmoz, Jul 13, 2017, 10:17:35 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