| Index: pkg/barback/example/aggregate_transformer/lib/transformer.dart
|
| diff --git a/pkg/barback/example/aggregate_transformer/lib/transformer.dart b/pkg/barback/example/aggregate_transformer/lib/transformer.dart
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..bf6b2c300b4e2998568e9b19b878610a294dd824
|
| --- /dev/null
|
| +++ b/pkg/barback/example/aggregate_transformer/lib/transformer.dart
|
| @@ -0,0 +1,53 @@
|
| +// 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()));
|
| + });
|
| + }
|
| +}
|
| +
|
|
|
Chromium Code Reviews
Issue 429943004:
Adding an aggregate transformer example to barback. Also updating the previous examples. (Closed)
Base URL: https://dart.googlecode.com/svn/branches/bleeding_edge/dart