| // Copyright (c) 2013, 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. |
| |
| /** Transfomer that combines multiple dart script tags into a single one. */ |
| library polymer.src.build.script_compactor; |
| |
| import 'dart:async'; |
| import 'dart:convert'; |
| |
| import 'package:barback/barback.dart'; |
| import 'package:html5lib/parser.dart' show parseFragment; |
| import 'package:path/path.dart' as path; |
| |
| import 'code_extractor.dart'; // import just for documentation. |
| import 'common.dart'; |
| |
| /** |
| * Combines Dart script tags into a single script tag, and creates a new Dart |
| * file that calls the main function of each of the original script tags. |
| * |
| * This transformer assumes that all script tags point to external files. To |
| * support script tags with inlined code, use this transformer after running |
| * [InlineCodeExtractor] on an earlier phase. |
| * |
| * Internally, this transformer will convert each script tag into an import |
| * statement to a library, and then uses `initPolymer` (see polymer.dart) to |
| * process `@initMethod` and `@CustomTag` annotations in those libraries. |
| */ |
| class ScriptCompactor extends Transformer with PolymerTransformer { |
| final TransformOptions options; |
| |
| ScriptCompactor(this.options); |
| |
| /** Only run on entry point .html files. */ |
| Future<bool> isPrimary(Asset input) => |
| new Future.value(options.isHtmlEntryPoint(input.id)); |
| |
| Future apply(Transform transform) { |
| var id = transform.primaryInput.id; |
| var secondaryId = id.addExtension('.scriptUrls'); |
| var logger = transform.logger; |
| return readPrimaryAsHtml(transform).then((document) { |
| return transform.readInputAsString(secondaryId).then((libraryIds) { |
| var libraries = JSON.decode(libraryIds).map( |
| (data) => new AssetId.deserialize(data)).toList(); |
| var mainLibraryId; |
| var mainScriptTag; |
| bool changed = false; |
| |
| for (var tag in document.queryAll('script')) { |
| var src = tag.attributes['src']; |
| if (src == 'packages/polymer/boot.js') { |
| tag.remove(); |
| continue; |
| } |
| if (tag.attributes['type'] != 'application/dart') continue; |
| if (src == null) { |
| logger.warning('unexpected script without a src url. The ' |
| 'ScriptCompactor transformer should run after running the ' |
| 'InlineCodeExtractor', span: tag.sourceSpan); |
| continue; |
| } |
| if (mainLibraryId != null) { |
| logger.warning('unexpected script. Only one Dart script tag ' |
| 'per document is allowed.', span: tag.sourceSpan); |
| tag.remove(); |
| continue; |
| } |
| mainLibraryId = resolve(id, src, logger, tag.sourceSpan); |
| mainScriptTag = tag; |
| } |
| |
| if (mainScriptTag == null) { |
| // We didn't find any main library, nothing to do. |
| transform.addOutput(transform.primaryInput); |
| return; |
| } |
| |
| var bootstrapId = id.addExtension('_bootstrap.dart'); |
| mainScriptTag.attributes['src'] = |
| path.url.basename(bootstrapId.path); |
| |
| // TODO(sigmund): stop renaming the file (see dartbug.com/14554) |
| var modifiedMainId = mainLibraryId.addExtension('_modified.dart'); |
| |
| libraries.add(modifiedMainId); |
| var urls = libraries.map((id) => assetUrlFor(id, bootstrapId, logger)) |
| .where((url) => url != null).toList(); |
| var buffer = new StringBuffer()..writeln(MAIN_HEADER); |
| int i = 0; |
| for (; i < urls.length; i++) { |
| buffer.writeln("import '${urls[i]}' as i$i;"); |
| } |
| |
| buffer..write('\n') |
| ..writeln('void main() {') |
| ..writeln(' configureForDeployment([') |
| ..writeAll(urls.map((url) => " '$url',\n")) |
| ..writeln(' ]);') |
| ..writeln(' i${i - 1}.polymerMainWrapper();') |
| ..writeln('}'); |
| |
| transform.addOutput(new Asset.fromString( |
| bootstrapId, buffer.toString())); |
| transform.addOutput(new Asset.fromString(id, document.outerHtml)); |
| |
| return transform.readInputAsString(mainLibraryId).then((contents) { |
| transform.addOutput(new Asset.fromString(modifiedMainId, |
| '$contents\n\npolymerMainWrapper() => main();\n')); |
| }); |
| }); |
| }); |
| } |
| } |
| |
| const MAIN_HEADER = """ |
| library app_bootstrap; |
| |
| import 'package:polymer/polymer.dart'; |
| """; |