// Copyright 2014 The Flutter Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. // @dart = 2.8 import 'package:meta/meta.dart'; import '../base/common.dart'; import '../build_info.dart'; import '../build_system/targets/web.dart'; import '../features.dart'; import '../globals_null_migrated.dart' as globals; import '../project.dart'; import '../runner/flutter_command.dart' show DevelopmentArtifact, FlutterCommandResult; import '../web/compile.dart'; import 'build.dart'; class BuildWebCommand extends BuildSubCommand { BuildWebCommand({ @required bool verboseHelp, }) { addTreeShakeIconsFlag(enabledByDefault: false); usesTargetOption(); usesPubOption(); addBuildModeFlags(verboseHelp: verboseHelp, excludeDebug: true); usesDartDefineOption(); usesWebRendererOption(); addEnableExperimentation(hide: !verboseHelp); addNullSafetyModeOptions(hide: !verboseHelp); addNativeNullAssertions(); argParser.addFlag('csp', defaultsTo: false, negatable: false, help: 'Disable dynamic generation of code in the generated output. ' 'This is necessary to satisfy CSP restrictions (see http://www.w3.org/TR/CSP/).' ); argParser.addFlag( 'source-maps', defaultsTo: false, help: 'Generate a sourcemap file. These can be used by browsers ' 'to view and debug the original source code of a compiled and minified Dart ' 'application.' ); argParser.addOption('pwa-strategy', defaultsTo: kOfflineFirst, help: 'The caching strategy to be used by the PWA service worker.', allowed: <String>[ kOfflineFirst, kNoneWorker, ], allowedHelp: <String, String>{ kOfflineFirst: 'Attempt to cache the application shell eagerly and ' 'then lazily cache all subsequent assets as they are loaded. When ' 'making a network request for an asset, the offline cache will be ' 'preferred.', kNoneWorker: 'Generate a service worker with no body. This is useful for ' 'local testing or in cases where the service worker caching functionality ' 'is not desirable', }, ); argParser.addOption('base-href', help: 'Overrides the href attribute of the <base> tag in web/index.html. ' 'No change is done to web/index.html file if this flag is not provided. ' 'The value has to start and end with a slash "/". ' 'For more information: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/base' ); } @override Future<Set<DevelopmentArtifact>> get requiredArtifacts async => const <DevelopmentArtifact>{ DevelopmentArtifact.web, }; @override final String name = 'web'; @override bool get hidden => !featureFlags.isWebEnabled; @override final String description = 'Build a web application bundle.'; @override Future<FlutterCommandResult> runCommand() async { if (!featureFlags.isWebEnabled) { throwToolExit('"build web" is not currently supported. To enable, run "flutter config --enable-web".'); } final FlutterProject flutterProject = FlutterProject.current(); final String target = stringArg('target'); final BuildInfo buildInfo = await getBuildInfo(); if (buildInfo.isDebug) { throwToolExit('debug builds cannot be built directly for the web. Try using "flutter run"'); } if (stringArg('base-href') != null && !(stringArg('base-href').startsWith('/') && stringArg('base-href').endsWith('/'))) { throwToolExit('base-href should start and end with /'); } if (!flutterProject.web.existsSync()) { throwToolExit('Missing index.html.'); } if (!globals.fs.currentDirectory .childDirectory('web') .childFile('index.html') .readAsStringSync() .contains(kBaseHrefPlaceholder) && stringArg('base-href') != null) { throwToolExit( "Couldn't find the placeholder for base href. " r'Please add `<base href="$FLUTTER_BASE_HREF">` to web/index.html' ); } displayNullSafetyMode(buildInfo); await buildWeb( flutterProject, target, buildInfo, boolArg('csp'), stringArg('pwa-strategy'), boolArg('source-maps'), boolArg('native-null-assertions'), stringArg('base-href'), ); return FlutterCommandResult.success(); } }