chrome.syncFileSystem

Description

Use the chrome.syncFileSystem API to save and synchronize data on Google Drive. This API is NOT for accessing arbitrary user docs stored in Google Drive. It provides app-specific syncable storage for offline and caching usage so that the same data can be available across different clients. Read Manage Data for more on using this API.

Permissions

syncFileSystem

Types

ConflictResolutionPolicy

Enum

"last_write_win"

"manual"

FileInfo

Properties

  • action

    SyncAction optional

    Sync action taken to fire onFileStatusChanged event. The action value can be 'added', 'updated' or 'deleted'. Only applies if status is 'synced'.

  • direction

    SyncDirection optional

    Sync direction for the onFileStatusChanged event. Sync direction value can be 'local_to_remote' or 'remote_to_local'. Only applies if status is 'synced'.

  • fileEntry

    Entry

    fileEntry for the target file whose status has changed. Contains name and path information of synchronized file. On file deletion, fileEntry information will still be available but file will no longer exist.

  • status

    FileStatus

    Resulting file status after onFileStatusChanged event. The status value can be 'synced', 'pending' or 'conflicting'.

FileStatus

Enum

"synced"
Not conflicting and has no pending local changes.

"pending"
Has one or more pending local changes that haven't been synchronized.

"conflicting"
File conflicts with remote version and must be resolved manually.

FileStatusInfo

Properties

  • error

    string optional

    Optional error that is only returned if there was a problem retrieving the FileStatus for the given file.

  • fileEntry

    Entry

    One of the Entry's originally given to getFileStatuses.

  • status

    FileStatus

    The status value can be 'synced', 'pending' or 'conflicting'.

ServiceInfo

Properties

ServiceStatus

Enum

"initializing"
The sync service is being initialized (e.g. restoring data from the database, checking connectivity and authenticating to the service etc).

"running"
The sync service is up and running.

"authentication_required"
The sync service is not synchronizing files because the remote service needs to be authenticated by the user to proceed.

"temporary_unavailable"
The sync service is not synchronizing files because the remote service is (temporarily) unavailable due to some recoverable errors, e.g. network is offline, the remote service is down or not reachable etc. More details should be given by description parameter in OnServiceInfoUpdated (which could contain service-specific details).

"disabled"
The sync service is disabled and the content will never sync. (E.g. this could happen when the user has no account on the remote service or the sync service has had an unrecoverable error.)

StorageInfo

Properties

  • quotaBytes

    number

  • usageBytes

    number

SyncAction

Enum

"added"

"updated"

"deleted"

SyncDirection

Enum

"local_to_remote"

"remote_to_local"

Methods

getConflictResolutionPolicy()

Promise 
chrome.syncFileSystem.getConflictResolutionPolicy(
  callback?: function,
): Promise<ConflictResolutionPolicy>

Gets the current conflict resolution policy.

Parameters

Returns

  • Chrome 117+

    Promises are only supported for Manifest V3 and later, other platforms need to use callbacks.

getFileStatus()

Promise 
chrome.syncFileSystem.getFileStatus(
  fileEntry: Entry,
  callback?: function,
): Promise<FileStatus>

Returns the FileStatus for the given fileEntry. The status value can be 'synced', 'pending' or 'conflicting'. Note that 'conflicting' state only happens when the service's conflict resolution policy is set to 'manual'.

Parameters

  • fileEntry

    Entry

  • callback

    function optional

    The callback parameter looks like: 

    (status: FileStatus) => void

Returns

  • Promise<FileStatus>

    Chrome 117+

    Promises are only supported for Manifest V3 and later, other platforms need to use callbacks.

getFileStatuses()

Promise 
chrome.syncFileSystem.getFileStatuses(
  fileEntries: object[],
  callback?: function,
): Promise<FileStatusInfo[]>

Returns each FileStatus for the given fileEntry array. Typically called with the result from dirReader.readEntries().

Parameters

  • fileEntries

    object[]

  • callback

    function optional

    The callback parameter looks like: 

    (status: FileStatusInfo[]) => void

Returns

  • Promise<FileStatusInfo[]>

    Chrome 117+

    Promises are only supported for Manifest V3 and later, other platforms need to use callbacks.

getServiceStatus()

Promise 
chrome.syncFileSystem.getServiceStatus(
  callback?: function,
): Promise<ServiceStatus>

Returns the current sync backend status.

Parameters

Returns

  • Promise<ServiceStatus>

    Chrome 117+

    Promises are only supported for Manifest V3 and later, other platforms need to use callbacks.

getUsageAndQuota()

Promise 
chrome.syncFileSystem.getUsageAndQuota(
  fileSystem: DOMFileSystem,
  callback?: function,
): Promise<StorageInfo>

Returns the current usage and quota in bytes for the 'syncable' file storage for the app.

Parameters

  • fileSystem

    DOMFileSystem

  • callback

    function optional

    The callback parameter looks like: 

    (info: StorageInfo) => void

Returns

  • Promise<StorageInfo>

    Chrome 117+

    Promises are only supported for Manifest V3 and later, other platforms need to use callbacks.

requestFileSystem()

Promise 
chrome.syncFileSystem.requestFileSystem(
  callback?: function,
): Promise<DOMFileSystem>

Returns a syncable filesystem backed by Google Drive. The returned DOMFileSystem instance can be operated on in the same way as the Temporary and Persistant file systems (see http://dev.w3.org/2009/dap/file-system/file-dir-sys.html).

Calling this multiple times from the same app will return the same handle to the same file system.

Note this call can fail. For example, if the user is not signed in to Chrome or if there is no network operation. To handle these errors it is important chrome.runtime.lastError is checked in the callback.

Parameters

  • callback

    function optional

    The callback parameter looks like: 

    (fileSystem: DOMFileSystem) => void

    • fileSystem

      DOMFileSystem

Returns

  • Promise<DOMFileSystem>

    Chrome 117+

    Promises are only supported for Manifest V3 and later, other platforms need to use callbacks.

setConflictResolutionPolicy()

Promise 
chrome.syncFileSystem.setConflictResolutionPolicy(
  policy: ConflictResolutionPolicy,
  callback?: function,
): Promise<void>

Sets the default conflict resolution policy for the 'syncable' file storage for the app. By default it is set to 'last_write_win'. When conflict resolution policy is set to 'last_write_win' conflicts for existing files are automatically resolved next time the file is updated. callback can be optionally given to know if the request has succeeded or not.

Parameters

Returns

  • Promise<void>

    Chrome 117+

    Promises are only supported for Manifest V3 and later, other platforms need to use callbacks.

Events

onFileStatusChanged

chrome.syncFileSystem.onFileStatusChanged.addListener(
  callback: function,
)

Fired when a file has been updated by the background sync service.

Parameters

  • callback

    function

    The callback parameter looks like: 

    (detail: FileInfo) => void

onServiceStatusChanged

chrome.syncFileSystem.onServiceStatusChanged.addListener(
  callback: function,
)

Fired when an error or other status change has happened in the sync backend (for example, when the sync is temporarily disabled due to network or authentication error).

Parameters