tool/lib/commands/rollback.dart

// Copyright 2020 The Flutter Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file or at https://developers.google.com/open-source/licenses/bsd.

import 'dart:async';
import 'dart:io' as io;

import 'package:args/command_runner.dart';

import '../model.dart';

const _toVersionArg = 'to-version';

class RollbackCommand extends Command {
  RollbackCommand() : super() {
    argParser.addOption(_toVersionArg, mandatory: true);
  }

  @override
  String get name => 'rollback';

  @override
  String get description => 'Rolls back to a specific DevTools version.';

  @override
  Future run() async {
    final repo = DevToolsRepo.getInstance();
    print('DevTools repo at ${repo.repoPath}.');

    final tempDir = (await io.Directory.systemTemp.createTemp(
      'devtools-rollback',
    )).absolute;
    try {
      print('file://${tempDir.path}');
      final tarball = io.File('${tempDir.path}/devtools.tar.gz');
      final extractDir = await io.Directory(
        '${tempDir.path}/extract/',
      ).absolute.create();
      final client = io.HttpClient();
      final version = argResults![_toVersionArg] as String;
      print('downloading tarball to ${tarball.path}');
      final tarballRequest = await client.getUrl(
        Uri.http(
          'storage.googleapis.com',
          'pub-packages/packages/devtools-$version.tar.gz',
        ),
      );
      final tarballResponse = await tarballRequest.close();
      await tarballResponse.pipe(tarball.openWrite());
      print('Tarball written; unzipping.');

      await io.Process.run('tar', [
        '-x',
        '-z',
        '-f',
        tarball.path.split('/').last,
        '-C',
        extractDir.path,
      ], workingDirectory: tempDir.path);
      print('file://${tempDir.path}');

      final buildDir = io.Directory(
        '${repo.repoPath}/packages/devtools/build/',
      );
      await buildDir.delete(recursive: true);
      await io.Directory(
        '${extractDir.path}build/',
      ).rename('${repo.repoPath}/packages/devtools/build/');

      print(
        'Build outputs from Devtools version $version checked out and moved '
        'to ${buildDir.path}',
      );
      print(
        'To complete the rollback, go to ${repo.repoPath}/packages/devtools, '
        'rev pubspec.yaml, update the changelog, unhide build/ from the '
        'packages/devtools/.gitignore file, then run pub publish.',
      );
      // TODO(djshuckerow): automatically rev pubspec.yaml and update the
      // changelog so that the user can just run pub publish from
      // packages/devtools.
    } finally {
      if (await tempDir.exists()) {
        await tempDir.delete(recursive: true);
      }
    }
  }
}