ZstdCodec class

Codec for compressing and uncompressing data that arrives in pieces, the way transform from Stream<List<int>> sends it.

Ideal for usage during network downloads/uploads without creating temporary files

Behaviour is identical to gzip and zlib from dart:io, except for TAR, ZIP and codecs that are used with MultithreadOptions, which only differ in closing the sink on failure.

ZstdMultithreadOptions is available only for zstdCodec.encoder and XZMultithreadOptions for xzCodec.decoder.

Please note that onDone may never be called on failure, you have to listen for both onError and onDone to identify the end of stream. Example for .decoder:

import 'package:archive/archive.dart';
import 'dart:io';
import 'package:path/path.dart' as p;

final request = await HttpClient()
    .getUrl(Uri.parse('https://example.com/data.tar.zst'));
final HttpClientResponse response = await request.close();

await for (final TarEntry entry in response
    // also available for xz/zstd/bzip2/tar
    .transform(zstdCodec.decoder)
    .transform(tarCodec.decoder)) {
  final target = p.join('out', entry.name);
  if (!p.isWithin('out', target)) continue; // `../` would escape out/
  if (entry.type == TarEntryType.file) {
    await File(target).create(recursive: true);
    await entry.content.pipe(File(target).openWrite());
  }
}

Example for .encoder:

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

final out = File('data.xz').openWrite();
await File('data')
    .openRead()
    // also available for xz/zstd/bzip2/tar/zip
    .transform(xzCodec.encoder)
    .pipe(out);