| // Copyright (c) 2014, 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 'package:barback/barback.dart'; |
| import 'package:path/path.dart' as p; |
| |
| import 'dart:async'; |
| |
| class MakeBook extends AggregateTransformer { |
| // All transformers need to implement "asPlugin" to let Pub know that they |
| // are transformers. |
| MakeBook.asPlugin(); |
| |
| // Implement the classifyPrimary method to claim any assets that you want |
| // to handle. Return a value for the assets you want to handle, |
| // or null for those that you do not want to handle. |
| classifyPrimary(AssetId id) { |
| // Only process assets where the filename ends with "recipe.html". |
| if (!id.path.endsWith('recipe.html')) return null; |
| |
| // Return the path string, minus the recipe itself. |
| // This is where the output asset will be written. |
| return p.url.dirname(id.path); |
| } |
| |
| // Implement the apply method to process the assets and create the |
| // output asset. |
| Future apply(AggregateTransform transform) { |
| var buffer = new StringBuffer()..write('<html><body>'); |
| |
| return transform.primaryInputs.toList().then((assets) { |
| // The order of [transform.primaryInputs] is not guaranteed |
| // to be stable across multiple runs of the transformer. |
| // Therefore, we alphabetically sort the assets by ID string. |
| assets.sort((x, y) => x.id.compareTo(y.id)); |
| return Future.wait(assets.map((asset) { |
| return asset.readAsString().then((content) { |
| buffer.write(content); |
| buffer.write('<hr>'); |
| }); |
| })); |
| }).then((_) { |
| buffer.write('</body></html>'); |
| // Write the output back to the same directory, |
| // in a file named recipes.html. |
| var id = new AssetId(transform.package, |
| p.url.join(transform.key, ".recipes.html")); |
| transform.addOutput(new Asset.fromString(id, buffer.toString())); |
| }); |
| } |
| } |
| |
