[native_assets_cli] Version protocol between Dart SDK and packages (#26)

pkgs/native_assets_cli/lib/src/model/build_config.dart

@@ -4,6 +4,7 @@
 
 import 'package:cli_config/cli_config.dart';
 import 'package:collection/collection.dart';
+import 'package:pub_semver/pub_semver.dart';
 
 import '../utils/map.dart';
 import '../utils/yaml.dart';
@@ -105,6 +106,16 @@ class BuildConfig {
 
   BuildConfig._();
 
+  /// The version of [BuildConfig].
+  ///
+  /// This class is used in the protocol between the Dart and Flutter SDKs
+  /// and packages through `build.dart` invocations.
+  ///
+  /// If we ever were to make breaking changes, it would be useful to give
+  /// proper error messages rather than just fail to parse the YAML
+  /// representation in the protocol.
+  static Version version = Version(1, 0, 0);
+
   factory BuildConfig.fromConfig(Config config) {
     final result = BuildConfig._();
     final configExceptions = <Object>[];
@@ -159,11 +170,29 @@ class BuildConfig {
   static const toolchainEnvScriptArgsConfigKey =
       'toolchain_env_script_arguments';
   static const dependencyMetadataConfigKey = 'dependency_metadata';
+  static const _versionKey = 'version';
 
   List<void Function(Config)> _readFieldsFromConfig() {
     var targetSet = false;
     var ccSet = false;
     return [
+      (config) {
+        final configVersion = Version.parse(config.string('version'));
+        if (configVersion.major > version.major) {
+          throw FormatException(
+            'The config version $configVersion is newer than this '
+            'package:native_assets_cli config version $version, '
+            'please update native_assets_cli.',
+          );
+        }
+        if (configVersion.major < version.major) {
+          throw FormatException(
+            'The config version $configVersion is newer than this '
+            'package:native_assets_cli config version $version, '
+            'please update the Dart or Flutter SDK.',
+          );
+        }
+      },
       (config) => _config = config,
       (config) => _outDir = config.path(outDirConfigKey),
       (config) => _packageRoot = config.path(packageRootConfigKey),
@@ -255,6 +284,7 @@ class BuildConfig {
             for (final entry in _dependencyMetadata!.entries)
               entry.key: entry.value.toYaml(),
           },
+        _versionKey: version.toString(),
       }.sortOnKey();
 
   String toYamlString() => yamlEncode(toYaml());

pkgs/native_assets_cli/lib/src/model/build_output.dart

@@ -5,6 +5,7 @@
 import 'dart:io';
 
 import 'package:collection/collection.dart';
+import 'package:pub_semver/pub_semver.dart';
 import 'package:yaml/yaml.dart';
 
 import '../utils/datetime.dart';
@@ -39,29 +40,59 @@ class BuildOutput {
   static const _dependenciesKey = 'dependencies';
   static const _metadataKey = 'metadata';
   static const _timestampKey = 'timestamp';
+  static const _versionKey = 'version';
 
   factory BuildOutput.fromYamlString(String yaml) {
     final yamlObject = loadYaml(yaml) as YamlMap;
     return BuildOutput.fromYaml(yamlObject);
   }
 
-  factory BuildOutput.fromYaml(YamlMap yamlMap) => BuildOutput(
-        timestamp: DateTime.parse(yamlMap[_timestampKey] as String),
-        assets: Asset.listFromYamlList(yamlMap[_assetsKey] as YamlList),
-        dependencies:
-            Dependencies.fromYaml(yamlMap[_dependenciesKey] as YamlList?),
-        metadata: Metadata.fromYaml(yamlMap[_metadataKey] as YamlMap?),
+  factory BuildOutput.fromYaml(YamlMap yamlMap) {
+    final outputVersion = Version.parse(yamlMap['version'] as String);
+    if (outputVersion.major > version.major) {
+      throw FormatException(
+        'The output version $outputVersion is newer than the '
+        'package:native_assets_cli config version $version in Dart or Flutter, '
+        'please update the Dart or Flutter SDK.',
       );
+    }
+    if (outputVersion.major < version.major) {
+      throw FormatException(
+        'The output version $outputVersion is newer than this '
+        'package:native_assets_cli config version $version in Dart or Flutter, '
+        'please update native_assets_cli.',
+      );
+    }
+
+    return BuildOutput(
+      timestamp: DateTime.parse(yamlMap[_timestampKey] as String),
+      assets: Asset.listFromYamlList(yamlMap[_assetsKey] as YamlList),
+      dependencies:
+          Dependencies.fromYaml(yamlMap[_dependenciesKey] as YamlList?),
+      metadata: Metadata.fromYaml(yamlMap[_metadataKey] as YamlMap?),
+    );
+  }
 
   Map<String, Object> toYaml() => {
         _timestampKey: timestamp.toString(),
         _assetsKey: assets.toYaml(),
         _dependenciesKey: dependencies.toYaml(),
         _metadataKey: metadata.toYaml(),
+        _versionKey: version.toString(),
       }..sortOnKey();
 
   String toYamlString() => yamlEncode(toYaml());
 
+  /// The version of [BuildOutput].
+  ///
+  /// This class is used in the protocol between the Dart and Flutter SDKs
+  /// and packages through `build.dart` invocations.
+  ///
+  /// If we ever were to make breaking changes, it would be useful to give
+  /// proper error messages rather than just fail to parse the YAML
+  /// representation in the protocol.
+  static Version version = Version(1, 0, 0);
+
   static const fileName = 'build_output.yaml';
 
   /// Writes the YAML file from [outDir]/[fileName].

pkgs/native_assets_cli/pubspec.yaml

@@ -9,6 +9,7 @@ environment:
 dependencies:
   cli_config: ^0.1.1
   collection: ^1.17.1
+  pub_semver: ^2.1.3
   yaml: ^3.1.1
   yaml_edit: ^2.1.0
 

pkgs/native_assets_cli/test/example/native_add_test.dart

@@ -41,6 +41,7 @@ void main() async {
         if (toolchainEnvScriptArgs != null)
           '-D${BuildConfig.toolchainEnvScriptArgsConfigKey}='
               '${toolchainEnvScriptArgs!.join(' ')}',
+        '-Dversion=${BuildConfig.version}',
       ],
       workingDirectory: testPackageUri.toFilePath(),
     );

pkgs/native_assets_cli/test/model/build_config_test.dart

@@ -79,6 +79,7 @@ void main() async {
       'package_root': tempUri.resolve('packageRoot/').toFilePath(),
       'target': 'android_arm64',
       'link_mode_preference': 'prefer-static',
+      'version': BuildOutput.version.toString(),
     });
 
     final fromConfig = BuildConfig.fromConfig(config);
@@ -175,7 +176,8 @@ link_mode_preference: prefer-static
 out_dir: ${outDir.toFilePath()}
 package_root: ${tempUri.toFilePath()}
 target: ios_arm64
-target_ios_sdk: iphoneos''';
+target_ios_sdk: iphoneos
+version: ${BuildConfig.version}''';
     expect(yamlString, equals(expectedYamlString));
 
     final buildConfig2 = BuildConfig.fromConfig(
@@ -298,4 +300,18 @@ target_ios_sdk: iphoneos''';
     final fromConfig = BuildConfig.fromConfig(config);
     expect(fromConfig, equals(buildConfig1));
   });
+
+  for (final version in ['9001.0.0', '0.0.1']) {
+    test('BuildConfig version $version', () {
+      final outDir = tempUri.resolve('out1/');
+      final config = Config(fileParsed: {
+        'link_mode_preference': 'prefer-static',
+        'out_dir': outDir.toFilePath(),
+        'package_root': tempUri.toFilePath(),
+        'target': 'linux_x64',
+        'version': version,
+      });
+      expect(() => BuildConfig.fromConfig(config), throwsFormatException);
+    });
+  }
 }

pkgs/native_assets_cli/test/model/build_output_test.dart

@@ -42,7 +42,7 @@ void main() {
     }),
   );
 
-  const yamlEncoding = '''timestamp: 2022-11-10 13:25:01.000
+  final yamlEncoding = '''timestamp: 2022-11-10 13:25:01.000
 assets:
   - name: foo
     link_mode: dynamic
@@ -59,7 +59,8 @@ assets:
 dependencies:
   - path/to/file.ext
 metadata:
-  key: value''';
+  key: value
+version: ${BuildOutput.version}''';
 
   test('built info yaml', () {
     final yaml = buildOutput.toYamlString().replaceAll('\\', '/');
@@ -94,4 +95,13 @@ metadata:
     );
     expect(buildOutput3.timestamp, DateTime.parse('2022-11-10 13:25:01.000'));
   });
+
+  for (final version in ['9001.0.0', '0.0.1']) {
+    test('BuildOutput version $version', () {
+      expect(
+        () => BuildOutput.fromYamlString('version: $version'),
+        throwsFormatException,
+      );
+    });
+  }
 }