Flutter UpChunk

Flutter UpChunk is a simple port of the JS library https://github.com/muxinc/upchunk done by MUX, Inc.

Installation

Add the package to the dependencies section in pubspec.yaml:

  • flutter_upchunk: ^2.1.0 (or latest release)

Usage

Add the following import to the .dart file that will use UpChunk

import 'package:flutter_upchunk/flutter_upchunk.dart';

Example

final uploadUrl = '';
final filePath = '';

// Chunk upload
var upChunkUpload = UpChunk(
  endPoint: uploadUrl,
  file: XFile(filePath),
  onProgress: (progress) {
    print('Upload progress: ${progress.ceil()}%');
  },
  onError: (String message, int chunk, int attempts) {
    print('UpChunk error 💥 🙀:');
    print(' - Message: $message');
    print(' - Chunk: $chunk');
    print(' - Attempts: $attempts');
  },
  onSuccess: (response) {
    print('Upload complete! 👋 (status: ${response.statusCode})');
  },
);

Or await the upload instead of using callbacks:

final upChunk = UpChunk(
  endPoint: uploadUrl,
  file: XFile(filePath),
  onProgress: (progress) => print('Upload progress: ${progress.ceil()}%'),
);

final response = await upChunk.done; // throws on failure or stop()
print('Upload complete! 👋 (status: ${response.statusCode})');

API

Although the API is a port of the original JS library, some options and properties differ slightly.

UpChunk constructor:

Upload options

  • endPoint type: string (required)

    URL to upload the file to.

  • file type: XFile (required)

    The file you'd like to upload.

  • headers type: Map<String, String>

    A Map with any headers you'd like included with the PUT request for each chunk.

  • chunkSize type: integer, default:5120

    The size in kb of the chunks to split the file into, with the exception of the final chunk which may be smaller. This parameter should be in multiples of 64.

  • attempts type: integer, default: 5

    The number of times to retry any given chunk.

  • delayBeforeRetry type: integer, default: 1

    The time in seconds to wait before attempting to upload a chunk again.

  • chunkStart type: integer, default: null

    The chunk number to start the upload from, useful in case the uploads fails in x chunk and the instance to the object is lost, UpChunk can pick up the upload from there.

Event options

  • onAttempt { chunkNumber: Integer, chunkSize: Integer }

    Fired immediately before a chunk upload is attempted. chunkNumber is the number of the current chunk being attempted, and chunkSize is the size (in bytes) of that chunk.

  • onAttemptFailure { message: String, chunkNumber: Integer, attemptsLeft: Integer }

    Fired when an attempt to upload a chunk fails.

  • onError { message: String, chunk: Integer, attempts: Integer }

    Fired when a chunk has reached the max number of retries or the response code is fatal and implies that retries should not be attempted.

  • onProgress progress double [0..100]

    Fired continuously with incremental upload progress. This returns the current percentage of the file that's been uploaded.

  • onSuccess { response: Response }

    Fired when the upload is finished successfully, with the HTTP response of the final chunk.

UpChunk Instance Methods

  • pause()

    Pauses an upload after the current in-flight chunk is finished uploading.

  • resume()

    Resumes an upload that was previously paused.

  • restart()

    Restarts the upload from chunk 0, use only if and after onError was fired.

  • stop()

    Cancels the upload abruptly. restart() can be used to start the upload from chunk 0.

UpChunk Instance Properties

  • done

    A Future<Response> that completes with the final chunk's HTTP response when the upload finishes, or completes with an error when the upload fails or stop() is called. After restart() it reflects the new attempt.

Note: connection drops are handled by the retry logic (attempts retries, delayBeforeRetry seconds apart) and end in onError — there is no internet-connection watchdog anymore.

Credit

Original code by MUX, Inc. and ported to Dart 🎯 with ❤ by a Flutter developer.

Libraries

flutter_upchunk