blob: 42f1a8fa1f9fa28a826a415d898e713d62fe0cd4 [file] [log] [blame]
// Copyright 2020 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:async';
import 'dart:collection';
import 'dart:convert';
import 'dart:io';
import 'package:fxtest/fxtest.dart';
import 'package:meta/meta.dart';
import 'package:path/path.dart' as p;
const _defaultManifest = 'package-repositories.json';
/// Contains information about a Fuchsia TUF package repository.
/// Meta information, like file system location, is collected from the file
/// 'package-repositories.json' produced by the Fuchsia build, while the
/// mapping of Fuchsia package URLs to their Merkle root hashes is collected
/// from a 'targets.json' file linked by the 'targets' property of
/// 'package-repositories.json'.
/// The 'targets.json' file is expected to follow the syntax defined in
/// and
class PackageRepository {
late String targetsFile;
late String blobsDirectory;
late String rootPath;
final Map<String, PackageInfo> _packages = {};
/// Parses a package-repositories.json manifest file, which points to a
/// [TUF]( repository.
/// The repository targets.json file is then parsed and produces a map of
/// package name and package variant to their corresponding Merkle root
/// hashes.
/// Returns null if the 'package-repositories.json' manifest doesn't exist
/// or if the 'targets.json' file referenced in property 'targets' of
/// 'package-repositories.json' cannot be opened.
static Future<PackageRepository>? fromManifest(
{required String buildDir, String repositoriesFile = _defaultManifest}) {
// The package-repositories manifest is usually very small, so it's ok to
// read it all at once.
File file = File(p.join(buildDir, repositoriesFile));
if (!file.existsSync()) {
return null;
String content = file.readAsStringSync();
try {
PackageRepository repository =
File targetsFile = File(p.join(buildDir, repository.targetsFile));
if (!targetsFile.existsSync()) {
return null;
// The targets.json file is usually large, so using a stream instead
return repository
.then((v) => repository);
} on PackageRepositoryException catch (e) {
// Wrap the exception to include the manifest filename
e.file = repositoriesFile;
// ignore: prefer_constructors_over_static_methods
static PackageUrl? decoratePackageUrlWithHash(
PackageRepository? repository, String? packageUrl) {
if (packageUrl == null) {
return null;
PackageUrl parsed = PackageUrl.fromString(packageUrl);
if (repository == null) {
return parsed;
PackageInfo? info = repository[parsed.packageName];
if (info == null) {
return parsed;
var hash = parsed.packageVariant == null
? info.merkle
: info[parsed.packageVariant!];
return PackageUrl.copyWithHash(other: parsed, hash: hash);
PackageRepository(this.targetsFile, this.blobsDirectory, this.rootPath);
/// Constructs a [PackageRepository] from the contents of a
/// package-repositories.json manifest file.
PackageRepository.fromJson(List<dynamic> manifest) {
if (manifest.length > 1) {
throw PackageRepositoryParseException(
'Multiple repositories are not supported');
if (manifest.isEmpty) {
throw PackageRepositoryParseException('No repository found in manifest');
Map<String, dynamic> repositoryJson = manifest[0];
targetsFile = repositoryJson['targets'];
blobsDirectory = repositoryJson['blobs'];
rootPath = repositoryJson['path'];
Future loadTargetsFromJson(Stream<Map<String, dynamic>> jsonStream) {
return jsonStream
// Filters objects with signed.targets content
.where((jsonObj) =>
jsonObj['signed'] != null && jsonObj['signed']['targets'] != null)
// Expands each signed.targets map into its entries
.expand((jsonObj) => jsonObj['signed']['targets'].entries)
// Merges target entries to _packages
// ignore: unnecessary_lambdas
.forEach((targetEntry) => _mergeTarget(targetEntry));
void _mergeTarget(MapEntry<String, dynamic> targetEntry) {
var split = targetEntry.key.split('/');
var name = split[0];
var variant = split[1];
_packages[name] =
PackageInfo.fromJson(name, variant, targetEntry.value, _packages[name]);
Map<String, PackageInfo> asMap() => UnmodifiableMapView(_packages);
PackageInfo? operator [](String packageName) => _packages[packageName];
class PackageInfo {
final String packageName;
/// Map package variant to its Merkle root hash
final Map<String, String> _merkle = {};
factory PackageInfo.fromJson(
String name, String variant, Map<String, dynamic> json,
[PackageInfo? current]) {
var packageInfo = current ?? PackageInfo._internal(name);
if (packageInfo._merkle.containsKey(variant)) {
throw PackageRepositoryParseException(
'Duplicated variant $variant for package $name in'
'package repository targets file');
packageInfo._merkle[variant] = json['custom']['merkle'];
return packageInfo;
/// Merkle root hash of the package for a given variant.
String? operator [](String? variant) {
return variant == null ? merkle : _merkle[variant];
/// Merkle root hash of the package.
/// Throws [PackageRepositoryException] if package has more than one variant.
String? get merkle {
if (_merkle.length > 1) {
throw PackageRepositoryException(
'Package $packageName has more than one variant, please specify one');
return _merkle.isEmpty ? null : _merkle.values.first;
String toString() {
return 'PackageInfo $packageName: $_merkle';