| // 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. |
| |
| library barback.graph.group_runner; |
| |
| import 'dart:async'; |
| |
| import '../asset/asset_node.dart'; |
| import '../log.dart'; |
| import '../transformer/transformer_group.dart'; |
| import '../utils/stream_pool.dart'; |
| import 'node_status.dart'; |
| import 'phase.dart'; |
| |
| /// A class that processes all of the phases in a single transformer group. |
| /// |
| /// A group takes many inputs, processes them, and emits many outputs. |
| class GroupRunner { |
| /// The group this runner runs. |
| final TransformerGroup _group; |
| |
| /// A string describing the location of [this] in the transformer graph. |
| final String _location; |
| |
| /// The phases defined by this group. |
| final _phases = new List<Phase>(); |
| |
| /// How far along [this] is in processing its assets. |
| NodeStatus get status { |
| // Just check the last phase, since it will check all the previous phases |
| // itself. |
| return _phases.last.status; |
| } |
| |
| /// A stream that emits an event every time the group's status changes. |
| Stream<NodeStatus> get onStatusChange => _onStatusChange; |
| Stream<NodeStatus> _onStatusChange; |
| |
| /// A stream that emits any new assets emitted by [this]. |
| /// |
| /// Assets are emitted synchronously to ensure that any changes are thoroughly |
| /// propagated as soon as they occur. |
| Stream<AssetNode> get onAsset => _onAsset; |
| Stream<AssetNode> _onAsset; |
| |
| /// A stream that emits an event whenever any transforms in this group logs |
| /// an entry. |
| Stream<LogEntry> get onLog => _onLogPool.stream; |
| final _onLogPool = new StreamPool<LogEntry>.broadcast(); |
| |
| GroupRunner(Phase previous, this._group, this._location) { |
| _addPhase(previous.addPhase(_location), []); |
| for (var phase in _group.phases) { |
| _addPhase(_phases.last.addPhase(), phase); |
| } |
| |
| _onAsset = _phases.last.onAsset; |
| _onStatusChange = _phases.last.onStatusChange; |
| } |
| |
| /// Add a phase with [contents] to [this]'s list of phases. |
| /// |
| /// [contents] should be an inner [Iterable] from a [TransformGroup.phases] |
| /// value. |
| void _addPhase(Phase phase, Iterable contents) { |
| _phases.add(phase); |
| _onLogPool.add(phase.onLog); |
| phase.updateTransformers(contents); |
| } |
| |
| /// Force all [LazyTransformer]s' transforms in this group to begin producing |
| /// concrete assets. |
| void forceAllTransforms() { |
| for (var phase in _phases) { |
| phase.forceAllTransforms(); |
| } |
| } |
| |
| /// Removes this group and all sub-phases within it. |
| void remove() { |
| _onLogPool.close(); |
| for (var phase in _phases) { |
| phase.remove(); |
| } |
| } |
| |
| String toString() => "group in phase $_location for $_group"; |
| } |