Combine tars and encode using archive lib

lib/api/archive.dart

@@ -1,33 +1,24 @@
 import 'dart:io';
 
-/// API for 7-Zip archive operations
+import 'package:archive/archive_io.dart';
+
+/// API for archive operations
 class ArchiveApi {
-  static const _exe = './7zip/7za.exe';
-
-  /// Get current path
-  static Future<String> get currentPath async {
-    // Get current path
-    try {
-      final result = await Process.run("cmd", ["/c", "cd"], runInShell: true);
-      return result.stdout.toString();
-    } catch (e) {
-      throw Exception('Failed to get current path: $e');
-    }
-  }
-
   /// Extracts the archive at [archivePath] to [destinationPath]
   static Future<void> extract(
       String archivePath, String destinationPath) async {
-    // 7zr.exe x layer2.tar.gz -olayer
     // Extract archive
-    try {
-      await Process.run(_exe, ['x', archivePath, '-o$destinationPath']);
-    } catch (e) {
-      throw Exception('Failed to extract archive: $e');
-    }
+    final inputStream = InputFileStream(archivePath);
+    final extracted = GZipDecoder().decodeBuffer(inputStream);
+    // Write to destination
+    final outputFile = File(destinationPath);
+    outputFile.create(recursive: true);
+    await outputFile.writeAsBytes(extracted);
+    inputStream.close();
   }
 
-  /// Merge the archives at [archivePaths] into [destinationPath]
+  /// Merge the tar archives at [archivePaths] into [destinationPath]
+  /// Trailing zeros are removed from the files.
   static Future<void> merge(
       List<String> archivePaths, String destinationPath) async {
     // Merge archives
@@ -65,14 +56,13 @@ class ArchiveApi {
   }
 
   /// Compress the tar archive at [filePath] to [destinationPath]
-  static Future<void> compress(String filePath, String destinationPath) async {
-    // 7zr.exe a -tgzip full_image.tar.gz full_image.tar
-    // Compress tar archive
-    try {
-      // 7zr.exe a -ttar combined_image.tar merged\*
-      await Process.run(_exe, ['a', '-tgzip', destinationPath, filePath]);
-    } catch (e) {
-      throw Exception('Failed to compress tar archive: $e');
-    }
+  static void compress(String filePath, String destinationPath) {
+    // compress tar to gzip
+    final inputFileStream = InputFileStream(filePath);
+    final outputFileStream = OutputFileStream(destinationPath);
+    GZipEncoder().encode(inputFileStream,
+        output: outputFileStream, level: Deflate.BEST_SPEED);
+    inputFileStream.close();
+    outputFileStream.close();
   }
 }

lib/api/docker_images.dart

@@ -450,13 +450,14 @@ class DockerImage {
 
             // Extract layer
             final layerTarGz = parentPath.file('layer_$i.tar.gz');
-            await ArchiveApi.extract(layerTarGz, parentPath.path);
-            paths.add(parentPath.file('layer_$i.tar'));
+            final layerTar = parentPath.file('layer_$i.tar');
+            await ArchiveApi.extract(layerTarGz, layerTar);
+            paths.add(layerTar);
           }
 
           // Archive as tar then gzip to disk
           await ArchiveApi.merge(paths, outTar);
-          await ArchiveApi.compress(outTar, outTarGz);
+          ArchiveApi.compress(outTar, outTarGz);
 
           Notify.message('writingtodisk-text'.i18n());
         } else if (layers == 1) {

test/dockerimages_test.dart

@@ -100,7 +100,7 @@ void main() {
 
     // Delete the instance
     await WSLApi().remove('test');
-  });
+  }, timeout: const Timeout(Duration(minutes: 2)));
 
   test('Create instance test nginx (nonroot)', () async {
     TextEditingController nameController = TextEditingController(text: 'test');