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chrome.downloads

  • Description

    Use the chrome.downloads API to programmatically initiate, monitor, manipulate, and search for downloads.

  • Permissions
    downloads

Manifest

You must declare the "downloads" permission in the extension manifest to use this API.

{
"name": "My extension",
...
"permissions": [
"downloads"
],
...
}

Examples

You can find simple examples of using the chrome.downloads API in the examples/api/downloads directory. For other examples and for help in viewing the source code, see Samples.

Summary

Types

BooleanDelta

Properties

  • current

    boolean optional

  • previous

    boolean optional

DangerType

file

The download's filename is suspicious.

url

The download's URL is known to be malicious.

content

The downloaded file is known to be malicious.

uncommon

The download's URL is not commonly downloaded and could be dangerous.

host

The download came from a host known to distribute malicious binaries and is likely dangerous.

unwanted

The download is potentially unwanted or unsafe. E.g. it could make changes to browser or computer settings.

safe

The download presents no known danger to the user's computer.

accepted

The user has accepted the dangerous download.

Type

"file"

,

"url"

,

"content"

,

"uncommon"

,

"host"

,

"unwanted"

,

"safe"

,
or

"accepted"

DoubleDelta

Properties

  • current

    number optional

  • previous

    number optional

DownloadDelta

Properties

  • canResume

    BooleanDelta optional

    The change in canResume, if any.

  • danger

    StringDelta optional

    The change in danger, if any.

  • endTime

    StringDelta optional

    The change in endTime, if any.

  • error

    StringDelta optional

    The change in error, if any.

  • exists

    BooleanDelta optional

    The change in exists, if any.

  • fileSize

    DoubleDelta optional

    The change in fileSize, if any.

  • filename

    StringDelta optional

    The change in filename, if any.

  • finalUrl

    StringDelta optional

    Chrome 54+

    The change in finalUrl, if any.

  • id

    number

    The id of the DownloadItem that changed.

  • mime

    StringDelta optional

    The change in mime, if any.

  • paused

    BooleanDelta optional

    The change in paused, if any.

  • startTime

    StringDelta optional

    The change in startTime, if any.

  • state

    StringDelta optional

    The change in state, if any.

  • totalBytes

    DoubleDelta optional

    The change in totalBytes, if any.

  • url

    StringDelta optional

    The change in url, if any.

DownloadItem

Properties

  • byExtensionId

    string optional

    The identifier for the extension that initiated this download if this download was initiated by an extension. Does not change once it is set.

  • byExtensionName

    string optional

    The localized name of the extension that initiated this download if this download was initiated by an extension. May change if the extension changes its name or if the user changes their locale.

  • bytesReceived

    number

    Number of bytes received so far from the host, without considering file compression.

  • canResume

    boolean

    True if the download is in progress and paused, or else if it is interrupted and can be resumed starting from where it was interrupted.

  • Indication of whether this download is thought to be safe or known to be suspicious.

  • endTime

    string optional

    The time when the download ended in ISO 8601 format. May be passed directly to the Date constructor: chrome.downloads.search({}, function(items){items.forEach(function(item){if (item.endTime) console.log(new Date(item.endTime))})})

  • error

    InterruptReason optional

    Why the download was interrupted. Several kinds of HTTP errors may be grouped under one of the errors beginning with SERVER_. Errors relating to the network begin with NETWORK_, errors relating to the process of writing the file to the file system begin with FILE_, and interruptions initiated by the user begin with USER_.

  • estimatedEndTime

    string optional

    Estimated time when the download will complete in ISO 8601 format. May be passed directly to the Date constructor: chrome.downloads.search({}, function(items){items.forEach(function(item){if (item.estimatedEndTime) console.log(new Date(item.estimatedEndTime))})})

  • exists

    boolean

    Whether the downloaded file still exists. This information may be out of date because Chrome does not automatically watch for file removal. Call search() in order to trigger the check for file existence. When the existence check completes, if the file has been deleted, then an onChanged event will fire. Note that search() does not wait for the existence check to finish before returning, so results from search() may not accurately reflect the file system. Also, search() may be called as often as necessary, but will not check for file existence any more frequently than once every 10 seconds.

  • fileSize

    number

    Number of bytes in the whole file post-decompression, or -1 if unknown.

  • filename

    string

    Absolute local path.

  • finalUrl

    string

    Chrome 54+

    The absolute URL that this download is being made from, after all redirects.

  • id

    number

    An identifier that is persistent across browser sessions.

  • incognito

    boolean

    False if this download is recorded in the history, true if it is not recorded.

  • mime

    string

    The file's MIME type.

  • paused

    boolean

    True if the download has stopped reading data from the host, but kept the connection open.

  • referrer

    string

    Absolute URL.

  • startTime

    string

    The time when the download began in ISO 8601 format. May be passed directly to the Date constructor: chrome.downloads.search({}, function(items){items.forEach(function(item){console.log(new Date(item.startTime))})})

  • state

    Indicates whether the download is progressing, interrupted, or complete.

  • totalBytes

    number

    Number of bytes in the whole file, without considering file compression, or -1 if unknown.

  • url

    string

    The absolute URL that this download initiated from, before any redirects.

DownloadOptions

Properties

  • body

    string optional

    Post body.

  • conflictAction

    The action to take if filename already exists.

  • filename

    string optional

    A file path relative to the Downloads directory to contain the downloaded file, possibly containing subdirectories. Absolute paths, empty paths, and paths containing back-references ".." will cause an error. onDeterminingFilename allows suggesting a filename after the file's MIME type and a tentative filename have been determined.

  • headers

    Extra HTTP headers to send with the request if the URL uses the HTTP[s] protocol. Each header is represented as a dictionary containing the keys name and either value or binaryValue, restricted to those allowed by XMLHttpRequest.

  • method

    HttpMethod optional

    The HTTP method to use if the URL uses the HTTP[S] protocol.

  • saveAs

    boolean optional

    Use a file-chooser to allow the user to select a filename regardless of whether filename is set or already exists.

  • url

    string

    The URL to download.

DownloadQuery

Properties

  • bytesReceived

    number optional

    Number of bytes received so far from the host, without considering file compression.

  • danger

    DangerType optional

    Indication of whether this download is thought to be safe or known to be suspicious.

  • endTime

    string optional

    The time when the download ended in ISO 8601 format.

  • endedAfter

    string optional

    Limits results to DownloadItem that ended after the given ms since the epoch.

  • endedBefore

    string optional

    Limits results to DownloadItem that ended before the given ms since the epoch.

  • error

    InterruptReason optional

    Why a download was interrupted.

  • exists

    boolean optional

    Whether the downloaded file exists;

  • fileSize

    number optional

    Number of bytes in the whole file post-decompression, or -1 if unknown.

  • filename

    string optional

    Absolute local path.

  • filenameRegex

    string optional

    Limits results to DownloadItem whose filename matches the given regular expression.

  • finalUrl

    string optional

    Chrome 54+

    The absolute URL that this download is being made from, after all redirects.

  • finalUrlRegex

    string optional

    Chrome 54+

    Limits results to DownloadItem whose finalUrl matches the given regular expression.

  • id

    number optional

    The id of the DownloadItem to query.

  • limit

    number optional

    The maximum number of matching DownloadItem returned. Defaults to 1000. Set to 0 in order to return all matching DownloadItem. See search for how to page through results.

  • mime

    string optional

    The file's MIME type.

  • orderBy

    string[] optional

    Set elements of this array to DownloadItem properties in order to sort search results. For example, setting orderBy=['startTime'] sorts the DownloadItem by their start time in ascending order. To specify descending order, prefix with a hyphen: '-startTime'.

  • paused

    boolean optional

    True if the download has stopped reading data from the host, but kept the connection open.

  • query

    string[] optional

    This array of search terms limits results to DownloadItem whose filename or url or finalUrl contain all of the search terms that do not begin with a dash '-' and none of the search terms that do begin with a dash.

  • startTime

    string optional

    The time when the download began in ISO 8601 format.

  • startedAfter

    string optional

    Limits results to DownloadItem that started after the given ms since the epoch.

  • startedBefore

    string optional

    Limits results to DownloadItem that started before the given ms since the epoch.

  • state

    State optional

    Indicates whether the download is progressing, interrupted, or complete.

  • totalBytes

    number optional

    Number of bytes in the whole file, without considering file compression, or -1 if unknown.

  • totalBytesGreater

    number optional

    Limits results to DownloadItem whose totalBytes is greater than the given integer.

  • totalBytesLess

    number optional

    Limits results to DownloadItem whose totalBytes is less than the given integer.

  • url

    string optional

    The absolute URL that this download initiated from, before any redirects.

  • urlRegex

    string optional

    Limits results to DownloadItem whose url matches the given regular expression.

FilenameConflictAction

uniquify

To avoid duplication, the filename is changed to include a counter before the filename extension.

overwrite

The existing file will be overwritten with the new file.

prompt

The user will be prompted with a file chooser dialog.

Type

"uniquify"

,

"overwrite"

,
or

"prompt"

FilenameSuggestion

Properties

  • conflictAction

    The action to take if filename already exists.

  • filename

    string

    The DownloadItem's new target DownloadItem.filename, as a path relative to the user's default Downloads directory, possibly containing subdirectories. Absolute paths, empty paths, and paths containing back-references ".." will be ignored. filename is ignored if there are any onDeterminingFilename listeners registered by any extensions.

GetFileIconOptions

Properties

  • size

    16 | 32 optional

    The size of the returned icon. The icon will be square with dimensions size * size pixels. The default and largest size for the icon is 32x32 pixels. The only supported sizes are 16 and 32. It is an error to specify any other size.

HeaderNameValuePair

Properties

  • name

    string

    Name of the HTTP header.

  • value

    string

    Value of the HTTP header.

HttpMethod

Type

"GET"

, or

"POST"

InterruptReason

Type

"FILE_FAILED"

,

"FILE_ACCESS_DENIED"

,

"FILE_NO_SPACE"

,

"FILE_NAME_TOO_LONG"

,

"FILE_TOO_LARGE"

,

"FILE_VIRUS_INFECTED"

,

"FILE_TRANSIENT_ERROR"

,

"FILE_BLOCKED"

,

"FILE_SECURITY_CHECK_FAILED"

,

"FILE_TOO_SHORT"

,

"FILE_HASH_MISMATCH"

,

"FILE_SAME_AS_SOURCE"

,

"NETWORK_FAILED"

,

"NETWORK_TIMEOUT"

,

"NETWORK_DISCONNECTED"

,

"NETWORK_SERVER_DOWN"

,

"NETWORK_INVALID_REQUEST"

,

"SERVER_FAILED"

,

"SERVER_NO_RANGE"

,

"SERVER_BAD_CONTENT"

,

"SERVER_UNAUTHORIZED"

,

"SERVER_CERT_PROBLEM"

,

"SERVER_FORBIDDEN"

,

"SERVER_UNREACHABLE"

,

"SERVER_CONTENT_LENGTH_MISMATCH"

,

"SERVER_CROSS_ORIGIN_REDIRECT"

,

"USER_CANCELED"

,

"USER_SHUTDOWN"

,
or

"CRASH"

State

in_progress

The download is currently receiving data from the server.

interrupted

An error broke the connection with the file host.

complete

The download completed successfully.

Type

"in_progress"

,

"interrupted"

,
or

"complete"

StringDelta

Properties

  • current

    string optional

  • previous

    string optional

Methods

acceptDanger

chrome.downloads.acceptDanger(
  downloadId: number,
  callback?: function,
)
Promise

Prompt the user to accept a dangerous download. Can only be called from a visible context (tab, window, or page/browser action popup). Does not automatically accept dangerous downloads. If the download is accepted, then an onChanged event will fire, otherwise nothing will happen. When all the data is fetched into a temporary file and either the download is not dangerous or the danger has been accepted, then the temporary file is renamed to the target filename, the state changes to 'complete', and onChanged fires.

Parameters

  • downloadId

    number

    The identifier for the DownloadItem.

  • callback

    function optional

    The callback parameter looks like: () => void

Returns

  • Promise<void>

    Pending

    This only returns a Promise when the callback parameter is not specified, and with MV3+. The type inside the Promise is the same as the 1st argument to callback.

cancel

chrome.downloads.cancel(
  downloadId: number,
  callback?: function,
)
Promise

Cancel a download. When callback is run, the download is cancelled, completed, interrupted or doesn't exist anymore.

Parameters

  • downloadId

    number

    The id of the download to cancel.

  • callback

    function optional

    The callback parameter looks like: () => void

Returns

  • Promise<void>

    Pending

    This only returns a Promise when the callback parameter is not specified, and with MV3+. The type inside the Promise is the same as the 1st argument to callback.

download

chrome.downloads.download(
  options: DownloadOptions,
  callback?: function,
)
Promise

Download a URL. If the URL uses the HTTP[S] protocol, then the request will include all cookies currently set for its hostname. If both filename and saveAs are specified, then the Save As dialog will be displayed, pre-populated with the specified filename. If the download started successfully, callback will be called with the new DownloadItem's downloadId. If there was an error starting the download, then callback will be called with downloadId=undefined and runtime.lastError will contain a descriptive string. The error strings are not guaranteed to remain backwards compatible between releases. Extensions must not parse it.

Parameters

  • What to download and how.

  • callback

    function optional

    The callback parameter looks like: (downloadId: number) => void

    • downloadId

      number

Returns

  • Promise<number>

    Pending

    This only returns a Promise when the callback parameter is not specified, and with MV3+. The type inside the Promise is the same as the 1st argument to callback.

erase

chrome.downloads.erase(
  query: DownloadQuery,
  callback?: function,
)
Promise

Erase matching DownloadItem from history without deleting the downloaded file. An onErased event will fire for each DownloadItem that matches query, then callback will be called.

Parameters

  • callback

    function optional

    The callback parameter looks like: (erasedIds: number[]) => void

    • erasedIds

      number[]

Returns

  • Promise<number[]>

    Pending

    This only returns a Promise when the callback parameter is not specified, and with MV3+. The type inside the Promise is the same as the 1st argument to callback.

getFileIcon

chrome.downloads.getFileIcon(
  downloadId: number,
  options?: GetFileIconOptions,
  callback?: function,
)
Promise

Retrieve an icon for the specified download. For new downloads, file icons are available after the onCreated event has been received. The image returned by this function while a download is in progress may be different from the image returned after the download is complete. Icon retrieval is done by querying the underlying operating system or toolkit depending on the platform. The icon that is returned will therefore depend on a number of factors including state of the download, platform, registered file types and visual theme. If a file icon cannot be determined, runtime.lastError will contain an error message.

Parameters

  • downloadId

    number

    The identifier for the download.

  • options
  • callback

    function optional

    The callback parameter looks like: (iconURL?: string) => void

    • iconURL

      string optional

Returns

  • Promise<string | undefined>

    Pending

    This only returns a Promise when the callback parameter is not specified, and with MV3+. The type inside the Promise is the same as the 1st argument to callback.

open

chrome.downloads.open(
  downloadId: number,
)

Open the downloaded file now if the DownloadItem is complete; otherwise returns an error through runtime.lastError. Requires the "downloads.open" permission in addition to the "downloads" permission. An onChanged event will fire when the item is opened for the first time.

Parameters

  • downloadId

    number

    The identifier for the downloaded file.

pause

chrome.downloads.pause(
  downloadId: number,
  callback?: function,
)
Promise

Pause the download. If the request was successful the download is in a paused state. Otherwise runtime.lastError contains an error message. The request will fail if the download is not active.

Parameters

  • downloadId

    number

    The id of the download to pause.

  • callback

    function optional

    The callback parameter looks like: () => void

Returns

  • Promise<void>

    Pending

    This only returns a Promise when the callback parameter is not specified, and with MV3+. The type inside the Promise is the same as the 1st argument to callback.

removeFile

chrome.downloads.removeFile(
  downloadId: number,
  callback?: function,
)
Promise

Remove the downloaded file if it exists and the DownloadItem is complete; otherwise return an error through runtime.lastError.

Parameters

  • downloadId

    number

  • callback

    function optional

    The callback parameter looks like: () => void

Returns

  • Promise<void>

    Pending

    This only returns a Promise when the callback parameter is not specified, and with MV3+. The type inside the Promise is the same as the 1st argument to callback.

resume

chrome.downloads.resume(
  downloadId: number,
  callback?: function,
)
Promise

Resume a paused download. If the request was successful the download is in progress and unpaused. Otherwise runtime.lastError contains an error message. The request will fail if the download is not active.

Parameters

  • downloadId

    number

    The id of the download to resume.

  • callback

    function optional

    The callback parameter looks like: () => void

Returns

  • Promise<void>

    Pending

    This only returns a Promise when the callback parameter is not specified, and with MV3+. The type inside the Promise is the same as the 1st argument to callback.

chrome.downloads.search(
  query: DownloadQuery,
  callback?: function,
)
Promise

Find DownloadItem. Set query to the empty object to get all DownloadItem. To get a specific DownloadItem, set only the id field. To page through a large number of items, set orderBy: ['-startTime'], set limit to the number of items per page, and set startedAfter to the startTime of the last item from the last page.

Parameters

Returns

  • Promise<DownloadItem[]>

    Pending

    This only returns a Promise when the callback parameter is not specified, and with MV3+. The type inside the Promise is the same as the 1st argument to callback.

setShelfEnabled

chrome.downloads.setShelfEnabled(
  enabled: boolean,
)

Enable or disable 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. Enabling the shelf while at least one other extension has disabled it will return an error through runtime.lastError. Requires the "downloads.shelf" permission in addition to the "downloads" permission.

Parameters

  • enabled

    boolean

show

chrome.downloads.show(
  downloadId: number,
)

Show the downloaded file in its folder in a file manager.

Parameters

  • downloadId

    number

    The identifier for the downloaded file.

showDefaultFolder

chrome.downloads.showDefaultFolder()

Show the default Downloads folder in a file manager.

Events

onChanged

chrome.downloads.onChanged.addListener(
  callback: function,
)

When any of a DownloadItem's properties except bytesReceived and estimatedEndTime changes, this event fires with the downloadId and an object containing the properties that changed.

Parameters

onCreated

chrome.downloads.onCreated.addListener(
  callback: function,
)

This event fires with the DownloadItem object when a download begins.

Parameters

onDeterminingFilename

chrome.downloads.onDeterminingFilename.addListener(
  callback: function,
)

During the filename determination process, extensions will be given the opportunity to override the target DownloadItem.filename. Each extension may not register more than one listener for this event. Each listener must call suggest exactly once, either synchronously or asynchronously. If the listener calls suggest asynchronously, then it must return true. If the listener neither calls suggest synchronously nor returns true, then suggest will be called automatically. The DownloadItem will not complete until all listeners have called suggest. Listeners may call suggest without any arguments in order to allow the download to use downloadItem.filename for its filename, or pass a suggestion object to suggest in order to override the target filename. If more than one extension overrides the filename, then the last extension installed whose listener passes a suggestion object to suggest wins. In order to avoid confusion regarding which extension will win, users should not install extensions that may conflict. If the download is initiated by download and the target filename is known before the MIME type and tentative filename have been determined, pass filename to download instead.

Parameters

onErased

chrome.downloads.onErased.addListener(
  callback: function,
)

Fires with the downloadId when a download is erased from history.

Parameters

  • callback

    function

    The callback parameter looks like: (downloadId: number) => void

    • downloadId

      number