background_downloader 4.2.0

A background file downloader and uploader. Define the task, enqueue and monitor progress

4.2.0

Added creationTime field to Request and Task.

Added allRecordsOlderThan(Duration age, {String? group} to Database, making it easy to extract the TaskRecord entries that are stale.

4.1.0

Adds optional tracking of task status and progress in a persistent database.

To keep track of the status and progress of all tasks, even after they have completed, activate tracking by calling trackTasks() and use the database field to query. For example:

    // at app startup, start tracking
    await FileDownloader().trackTasks();
    
    
    // somewhere else: enqueue a download
    final task = DownloadTask(
            url: 'https://google.com',
            filename: 'testfile.txt');
    final successfullyEnqueued = await FileDownloader().enqueue(task);
    
    // somewhere else: query the task status by getting a `TaskRecord`
    // from the database
    final record = await FileDownloader().database.recordForId(task.taskId);
    print('Taskid ${record.taskId} with task ${record.task} has '
        'status ${record.taskStatus} and progress ${record.progress}'

You can interact with the database using allRecords, recordForId, deleteAllRecords, deleteRecordWithId etc. Note that only tasks that you asked to be tracked (using trackTasks, which activates tracking for all tasks in a group) will be in the database. All active tasks in the queue, regardless of tracking, can be queried via the FileDownloader.taskForId call etc, but those will only return the task itself, not its status or progress, as those are expected to be monitored via listener or callback. Note: tasks that are started using download, upload, batchDownload or batchUpload are assigned a special group name 'await', as callbacks for these tasks are handled within the FileDownloader. If you want to track those tasks in the database, call FileDownloader().trackTasks(FileDownloader.awaitGroup) at the start of your app.

4.0.0

Adds support for MacOS, Windows and Linux and refactored the backend to be more easily extensible.

Changes FileDownloader usage from static to a singleton. This means that instead of calling FileDownloader.downloader(...) now call FileDownloader().downloader(...) etc.

Calling .initialize is not longer required.

3.0.1

iOS BaseDirectory.applicationSupport now uses iOS applicationSupportDirectory instead of libraryDirectory

3.0.0

Version 3 introduces uploads, onProgress and onStatus callbacks passed to download and upload, and cleans up the API to be less verbose.

The class hierarchy is Request -> Task -> (DownloadTask | UploadTask), and several methods and callbacks will return or expect a Task that may be a DownloadTask or UploadTask.

To align naming convention, several class and enum names have been changed:

• class BackgroundDownloadTask -> DownloadTask, and field progressUpdates -> updates
• enum DownloadTaskStatus -> TaskStatus
• enum DownloadProgressUpdates -> Updates (and enum value changes)
• class BackgroundDownloadEvent -> TaskUpdate
• class BackgroundDownloadStatusEvent -> TaskStatusUpdate
• class BackgroundDownloadProgressEvent -> TaskProgressUpdate
• typedef DownloadStatusCallback -> TaskStatusCallback
• typedef DownloadProgressCallback -> TaskProgressCallback
• class DownloadBatch -> Batch
• typedef BatchDownloadProgressCallback -> BatchProgressCallback

2.1.1

The url and urlQueryParameters passed to a BackgroundDownloadTask or Request must be encoded if necessary. For example, if the url or query parameters contain a space, it must be replaced with %20 per urlencoding

2.1.0

Changes:

• Added option to use a POST request: setting the post field to a String or UInt8List passes that data to the server using the POST method to obtain your file
• Added request method, taking a Request object (a superclass of BackgroundDownloadTask), for simple server requests, where you process the server response directly (i.e. not in a file).
• Refactored Android Kotlin code and made small improvement to the fix for issue with Firebase plugin onMethodCall handler

2.0.1

Fix for issue with Firebase plugin onMethodCall handler

2.0.0

Added option to automatically retry failed downloads. This is a breaking change, though for most existing implementations no or very little change is required.

The main change is the addition of enqueued and waitingToRetry status to the DownloadTaskStatus enum (and removal of undefined). As a result, when checking a DownloadStatusUpdate (e.g. using a switch statement) you need to cover these new cases (and for existing implementations can typically just ignore them). The progressUpdate equivalent of waitingToRetry is a value of -4.0, but for existing implementations this will never be emitted, as they won't have retries.

The second change is that a task now emits enqueued when enqueued, and running once the actual download (on the native platform) starts. In existing applications this can generally be ignored, but it allows for more precise status updates.

To use automatic retries, simply set the retries field of the BackgroundDownloadTask to an integer between 0 and 10. A normal download (without the need for retries) will follow status updates from enqueued -> running -> complete (or notFound). If retries has been set and the task fails, the sequence will be enqueued -> running -> waitingToRetry -> enqueued -> running -> complete (if the second try succeeds, or more retries if needed).

1.6.1

Fix for issue with Firebase plugin onMethodCall handler

1.6.0

Added option to set requiresWiFi on the BackgroundDownloadTask, which ensures the task won't start downloading unless a WiFi network is available. By default requiresWiFi is false, and downloads will use the cellular (or metered) network if WiFi is not available, which may incur cost.

1.5.0

Added allTasks method to get a list of running tasks. Use allTaskIds to get a list of taskIds only.

1.4.2

Added note to README referring to an issue ( and fix) where the firebase plugin interferes with the downloader

1.4.1

Improved example app, updated documentation and fixed minor Android bug

1.4.0

Added downloadBatch method to enqueue and wait for completion of a batch of downloads

1.3.0

Added option to use an event listener instead of (or in addition to) callbacks

1.2.0

Added FileDownloader.download as a convenience method for simple downloads. This method's Future completes only after the download has completed or failed, and can be used for simple downloads where status and progress checking is not required.

1.1.0

Added headers and metaData fields to the BackgroundDownloadTask. Headers will be added to the request, and metaData is ignored but may be helpful to the user

1.0.2

Replaced Ktor client with a basic Kotlin implementation

1.0.0

Initial release