flutter_file_upload #

Advanced file upload for Flutter with progress tracking, chunked uploads, and resume capability. Works on iOS, Android, Web, Windows, macOS, and Linux. WASM compatible.

Features #

• ✅ Streaming uploads with configurable chunk size
• ✅ Progress tracking via callback (bytesSent, totalBytes)
• ✅ Resume capability with shouldResumeFrom hook
• ✅ Platform detection - automatically selects Web or IO implementation
• ✅ Skip final request - optional parameter to skip verification request
• ✅ Pure Dart API - Flutter-friendly, no platform channels needed
• ✅ Cross-platform - iOS, Android, Web, Windows, macOS, Linux

Getting started #

Add the dependency to your pubspec.yaml:

dependencies:
  flutter_file_upload: ^0.1.0

Usage #

Basic Example #

import 'dart:io';
import 'package:flutter_file_upload/flutter_file_upload.dart';

Future<void> uploadFile() async {
  final file = File('path/to/big.file');
  final stream = file.openRead();
  final total = await file.length();

  // Automatically selects WebPlatformUploader or IoPlatformUploader
  final uploader = FileUploader(createPlatformUploader());

  final result = await uploader.upload(
    Uri.parse('https://example.com/upload'),
    byteStream: stream,
    totalByteLength: total,
    headers: {'Authorization': 'Bearer <token>'},
    chunkSizeBytes: 256 * 1024, // 256 KB chunks
    onProgress: (sent, total) {
      print('Progress: ${sent}/${total} bytes (${(sent / total * 100).toStringAsFixed(1)}%)');
    },
    shouldResumeFrom: (nextStart) async {
      // Return true to continue, false to skip/resume from different position
      return true;
    },
    skipFinalRequest: false, // Set to true to skip final GET verification
  );

  print('Upload complete! Status: ${result.statusCode}');
}

Platform-Specific Usage #

For explicit platform selection:

// For native platforms (iOS, Android, Windows, macOS, Linux)
final uploader = FileUploader(IoPlatformUploader());

// For Web
final uploader = FileUploader(WebPlatformUploader());

Skip Final Request #

Some servers don't support the final GET verification request. Use skipFinalRequest:

final result = await uploader.upload(
  Uri.parse('https://api.example.com/upload'),
  byteStream: stream,
  totalByteLength: total,
  skipFinalRequest: true, // Skip final GET request
);

Resume Strategy #

Implement custom resume logic:

shouldResumeFrom: (nextStart) async {
  // Check with server if upload already exists
  final serverStatus = await checkServerStatus(nextStart);
  if (serverStatus.alreadyUploaded) {
    return false; // Skip this chunk
  }
  return true; // Continue uploading
},

API Reference #

FileUploader.upload() #

Uploads a stream of bytes in chunks.

Parameters:

• url (required): The upload endpoint URI
• byteStream (required): Stream of bytes to upload
• totalByteLength: Total size in bytes (optional, for progress calculation)
• headers: HTTP headers to include with each request
• chunkSizeBytes: Size of each chunk in bytes (default: 256 KB)
• onProgress: Callback (bytesSent, totalBytes) called after each chunk
• shouldResumeFrom: Hook (nextByteStart) to control resume behavior
• skipFinalRequest: Skip final GET verification request (default: false)

Returns: UploadResult with status code, headers, and response body

Platform Support #

License #

See LICENSE file for details.