Add minimal bootstrapper for ddc_library_bundle format

dwds/CHANGELOG.md

@@ -5,6 +5,7 @@
 - Replace deprecated JS code `this.__proto__` with `Object.getPrototypeOf(this)`. - [#2500](https://github.com/dart-lang/webdev/pull/2500)
 - Migrate injected client code to `package:web`. - [#2491](https://github.com/dart-lang/webdev/pull/2491)
 - Deprecated MetadataProvider's, CompilerOptions', SdkConfiguration's & SdkLayout's soundNullSafety. - [#2427](https://github.com/dart-lang/webdev/issues/2427)
+- Add load strategy and an unimplemented hot restart strategy for DDC library bundle format.
 
 ## 24.1.0
 

dwds/lib/src/loaders/ddc.dart

@@ -17,7 +17,7 @@ String removeJsExtension(String path) =>
 String addJsExtension(String path) => '$path.js';
 
 /// JavaScript snippet to determine the base URL of the current path.
-const _baseUrlScript = '''
+const baseUrlScript = '''
 var baseUrl = (function () {
   // Attempt to detect --precompiled mode for tests, and set the base url
   // appropriately, otherwise set it to '/'.
@@ -179,7 +179,7 @@ class DdcStrategy extends LoadStrategy {
       scripts.add(<String, String>{'src': '$path.js', 'id': name});
     });
     return '''
-$_baseUrlScript
+$baseUrlScript
 var scripts = ${const JsonEncoder.withIndent(" ").convert(scripts)};
 window.\$dartLoader.loadConfig.loadScriptFn = function(loader) {
   loader.addScriptsToQueue(scripts, null);

dwds/lib/src/loaders/ddc_library_bundle.dart

@@ -0,0 +1,193 @@
+// Copyright (c) 2024, the Dart project authors.  Please see the AUTHORS file
+// for details. 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:convert';
+
+import 'package:dwds/src/debugging/metadata/provider.dart';
+import 'package:dwds/src/loaders/ddc.dart';
+import 'package:dwds/src/loaders/strategy.dart';
+import 'package:dwds/src/readers/asset_reader.dart';
+import 'package:dwds/src/services/expression_compiler.dart';
+import 'package:shelf/shelf.dart';
+
+// TODO(srujzs): This is mostly a copy of `DdcStrategy`. Some of the
+// functionality in here may not make sense with the library bundle format yet.
+class DdcLibraryBundleStrategy extends LoadStrategy {
+  @override
+  final ReloadConfiguration reloadConfiguration;
+
+  /// Returns a map of module name to corresponding server path (excluding .js)
+  /// for the provided Dart application entrypoint.
+  ///
+  /// For example:
+  ///
+  ///   web/main -> main.ddc
+  ///   packages/path/path -> packages/path/path.ddc
+  ///
+  final Future<Map<String, String>> Function(MetadataProvider metadataProvider)
+      _moduleProvider;
+
+  /// Returns a map of module name to corresponding digest value.
+  ///
+  /// For example:
+  ///
+  ///   web/main -> 8363b363f74b41cac955024ab8b94a3f
+  ///   packages/path/path -> d348c2a4647e998011fe305f74f22961
+  ///
+  final Future<Map<String, String>> Function(MetadataProvider metadataProvider)
+      // ignore: unused_field
+      _digestsProvider;
+
+  /// Returns the module for the corresponding server path.
+  ///
+  /// For example:
+  ///
+  /// /packages/path/path.ddc.js -> packages/path/path
+  ///
+  final Future<String?> Function(
+    MetadataProvider metadataProvider,
+    String sourcePath,
+  ) _moduleForServerPath;
+
+  /// Returns a map from module id to module info.
+  ///
+  /// For example:
+  ///
+  ///   web/main -> {main.ddc.full.dill, main.ddc.dill}
+  ///
+  final Future<Map<String, ModuleInfo>> Function(
+    MetadataProvider metadataProvider,
+  ) _moduleInfoForProvider;
+
+  /// Returns the server path for the provided module.
+  ///
+  /// For example:
+  ///
+  ///   web/main -> main.ddc.js
+  ///
+  final Future<String?> Function(
+    MetadataProvider metadataProvider,
+    String module,
+  ) _serverPathForModule;
+
+  /// Returns the source map path for the provided module.
+  ///
+  /// For example:
+  ///
+  ///   web/main -> main.ddc.js.map
+  ///
+  final Future<String?> Function(
+    MetadataProvider metadataProvider,
+    String module,
+  ) _sourceMapPathForModule;
+
+  /// Returns the server path for the app uri.
+  ///
+  /// For example:
+  ///
+  ///   org-dartlang-app://web/main.dart -> main.dart
+  ///
+  /// Will return `null` if the provided uri is not
+  /// an app URI.
+  final String? Function(String appUri) _serverPathForAppUri;
+
+  /// Returns the relative path in google3, determined by the [absolutePath].
+  ///
+  /// Returns `null` if not a google3 app.
+  final String? Function(String absolutePath) _g3RelativePath;
+
+  final BuildSettings _buildSettings;
+
+  DdcLibraryBundleStrategy(
+    this.reloadConfiguration,
+    this._moduleProvider,
+    this._digestsProvider,
+    this._moduleForServerPath,
+    this._serverPathForModule,
+    this._sourceMapPathForModule,
+    this._serverPathForAppUri,
+    this._moduleInfoForProvider,
+    AssetReader assetReader,
+    this._buildSettings,
+    this._g3RelativePath,
+    String? packageConfigPath,
+  ) : super(assetReader, packageConfigPath: packageConfigPath);
+
+  @override
+  Handler get handler => (request) async {
+        // TODO(markzipan): Implement a hot restarter that uses digests for
+        // the DDC module system.
+        return Response.notFound(request.url.toString());
+      };
+
+  @override
+  String get id => 'ddc-library-bundle';
+
+  // DDC doesn't have a 'ddc-library-bundle' format flag. Instead, it treats the
+  // combination of the DDC module format and canary mode as the DDC library
+  // bundle format, so we just pass 'ddc' here.
+  @override
+  String get moduleFormat => 'ddc';
+
+  @override
+  String get loadLibrariesModule => 'ddc_module_loader.ddk.js';
+
+  // TODO(srujzs): Refactor code that uses this to avoid loading individual
+  // libraries, as that's no longer supported in the new module format.
+  @override
+  String get loadModuleSnippet =>
+      "function() { throw new Error('LoadStrategy.loadModuleSnippet is used. "
+      "This is currently unsupported in the DDC library bundle format.'); }";
+
+  @override
+  Future<String> bootstrapFor(String entrypoint) async =>
+      await _ddcLoaderSetup(entrypoint);
+
+  @override
+  String loadClientSnippet(String clientScript) =>
+      'window.\$dartLoader.forceLoadModule("$clientScript");\n';
+
+  Future<String> _ddcLoaderSetup(String entrypoint) async {
+    final metadataProvider = metadataProviderFor(entrypoint);
+    final modulePaths = await _moduleProvider(metadataProvider);
+    final scripts = <Map<String, String?>>[];
+    modulePaths.forEach((name, path) {
+      scripts.add(<String, String>{'src': '$path.js', 'id': name});
+    });
+    return '''
+$baseUrlScript
+var scripts = ${const JsonEncoder.withIndent(" ").convert(scripts)};
+window.\$dartLoader.loadConfig.loadScriptFn = function(loader) {
+  loader.addScriptsToQueue(scripts, null);
+  loader.loadEnqueuedModules();
+};
+window.\$dartLoader.loader.nextAttempt();
+''';
+  }
+
+  @override
+  Future<String?> moduleForServerPath(String entrypoint, String serverPath) =>
+      _moduleForServerPath(metadataProviderFor(entrypoint), serverPath);
+
+  @override
+  Future<Map<String, ModuleInfo>> moduleInfoForEntrypoint(String entrypoint) =>
+      _moduleInfoForProvider(metadataProviderFor(entrypoint));
+
+  @override
+  Future<String?> serverPathForModule(String entrypoint, String module) =>
+      _serverPathForModule(metadataProviderFor(entrypoint), module);
+
+  @override
+  Future<String?> sourceMapPathForModule(String entrypoint, String module) =>
+      _sourceMapPathForModule(metadataProviderFor(entrypoint), module);
+
+  @override
+  String? serverPathForAppUri(String appUri) => _serverPathForAppUri(appUri);
+
+  @override
+  BuildSettings get buildSettings => _buildSettings;
+
+  @override
+  String? g3RelativePath(String absolutePath) => _g3RelativePath(absolutePath);
+}

dwds/lib/src/loaders/frontend_server_strategy_provider.dart

@@ -4,6 +4,7 @@
 
 import 'package:dwds/src/debugging/metadata/provider.dart';
 import 'package:dwds/src/loaders/ddc.dart';
+import 'package:dwds/src/loaders/ddc_library_bundle.dart';
 import 'package:dwds/src/loaders/require.dart';
 import 'package:dwds/src/loaders/strategy.dart';
 import 'package:dwds/src/readers/asset_reader.dart';
@@ -132,6 +133,38 @@ class FrontendServerDdcStrategyProvider
   DdcStrategy get strategy => _ddcStrategy;
 }
 
+/// Provides a [DdcLibraryBundleStrategy] suitable for use with the Frontend
+/// Server.
+class FrontendServerDdcLibraryBundleStrategyProvider
+    extends FrontendServerStrategyProvider<DdcLibraryBundleStrategy> {
+  late final DdcLibraryBundleStrategy _libraryBundleStrategy =
+      DdcLibraryBundleStrategy(
+    _configuration,
+    _moduleProvider,
+    (_) => _digestsProvider(),
+    _moduleForServerPath,
+    _serverPathForModule,
+    _sourceMapPathForModule,
+    _serverPathForAppUri,
+    _moduleInfoForProvider,
+    _assetReader,
+    _buildSettings,
+    (String _) => null,
+    null,
+  );
+
+  FrontendServerDdcLibraryBundleStrategyProvider(
+    super._configuration,
+    super._assetReader,
+    super._packageUriMapper,
+    super._digestsProvider,
+    super._buildSettings,
+  );
+
+  @override
+  DdcLibraryBundleStrategy get strategy => _libraryBundleStrategy;
+}
+
 /// Provides a [RequireStrategy] suitable for use with Frontend Server.
 class FrontendServerRequireStrategyProvider
     extends FrontendServerStrategyProvider<RequireStrategy> {

dwds/test/evaluate_common.dart

@@ -75,6 +75,7 @@ void testAll({
             enableExpressionEvaluation: true,
             useDebuggerModuleNames: useDebuggerModuleNames,
             verboseCompiler: debug,
+            canaryFeatures: provider.canaryFeatures,
           ),
         );
       });
@@ -832,6 +833,7 @@ void testAll({
           moduleFormat: provider.ddcModuleFormat,
           enableExpressionEvaluation: false,
           verboseCompiler: debug,
+          canaryFeatures: provider.canaryFeatures,
         ),
       );
     });

dwds/test/fixtures/context.dart

@@ -348,10 +348,13 @@ class TestContext {
                   buildSettings,
                 ).strategy,
               ModuleFormat.ddc => buildSettings.canaryFeatures
-                  ? throw Exception(
-                      '''Unsupported DDC module format ${testSettings.moduleFormat.name}
-                      with canaryFeatures set to ${buildSettings.canaryFeatures}.''',
-                    )
+                  ? FrontendServerDdcLibraryBundleStrategyProvider(
+                      testSettings.reloadConfiguration,
+                      assetReader,
+                      packageUriMapper,
+                      () async => {},
+                      buildSettings,
+                    ).strategy
                   : FrontendServerDdcStrategyProvider(
                       testSettings.reloadConfiguration,
                       assetReader,
@@ -370,8 +373,8 @@ class TestContext {
 
       final debugPort = await findUnusedPort();
       if (testSettings.launchChrome) {
-        // If the environment variable DWDS_DEBUG_CHROME is set to the string true
-        // then Chrome will be launched with a UI rather than headless.
+        // If the environment variable DWDS_DEBUG_CHROME is set to the string
+        // true then Chrome will be launched with a UI rather than headless.
         // If the extension is enabled, then Chrome will be launched with a UI
         // since headless Chrome does not support extensions.
         final enableDebugExtension = debugSettings.enableDebugExtension;

dwds/web/client.dart

@@ -24,10 +24,10 @@ import 'package:uuid/uuid.dart';
 import 'package:web/helpers.dart';
 import 'package:web_socket_channel/web_socket_channel.dart';
 
+import 'reloader/ddc_library_bundle_restarter.dart';
 import 'reloader/ddc_restarter.dart';
 import 'reloader/manager.dart';
 import 'reloader/require_restarter.dart';
-import 'reloader/restarter.dart';
 import 'run_main.dart';
 import 'web_utils.dart';
 
@@ -47,14 +47,12 @@ Future<void>? main() {
         ? WebSocketClient(WebSocketChannel.connect(fixedUri))
         : SseSocketClient(SseClient(fixedPath, debugKey: 'InjectedClient'));
 
-    Restarter restarter;
-    if (dartModuleStrategy == 'require-js') {
-      restarter = await RequireRestarter.create();
-    } else if (dartModuleStrategy == 'ddc' || dartModuleStrategy == 'legacy') {
-      restarter = DdcRestarter();
-    } else {
-      throw StateError('Unknown module strategy: $dartModuleStrategy');
-    }
+    final restarter = switch (dartModuleStrategy) {
+      'require-js' => await RequireRestarter.create(),
+      'ddc-library-bundle' => DdcLibraryBundleRestarter(),
+      'ddc' || 'legacy' => DdcRestarter(),
+      _ => throw StateError('Unknown module strategy: $dartModuleStrategy')
+    };
 
     final manager = ReloadingManager(client, restarter);
 

dwds/web/reloader/ddc_library_bundle_restarter.dart

@@ -0,0 +1,16 @@
+// Copyright (c) 2024, the Dart project authors.  Please see the AUTHORS file
+// for details. 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 'restarter.dart';
+
+class DdcLibraryBundleRestarter implements Restarter {
+  @override
+  Future<bool> restart({String? runId, Future? readyToRunMain}) async {
+    throw UnimplementedError(
+      "Hot reload isn't supported for the DDC library bundle format yet.",
+    );
+  }
+}

frontend_server_common/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.2.3-wip
+
+- Add bootstrapping code for DDC library bundle format.
+
 ## 0.2.2
 
 - Start the frontend server from the AOT snapshot shipped in the Dart SDK.