build_runner/lib/src/generate/watch_impl.dart - third_party/dart-pkg - Git at Google

 // Copyright (c) 2016, 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 'dart:async';

 import 'package:build/build.dart';
 import 'package:build_config/build_config.dart';
 import 'package:build_runner/src/package_graph/build_config_overrides.dart';
 import 'package:build_runner/src/watcher/asset_change.dart';
 import 'package:build_runner/src/watcher/change_filter.dart';
 import 'package:build_runner/src/watcher/collect_changes.dart';
 import 'package:build_runner/src/watcher/delete_writer.dart';
 import 'package:build_runner/src/watcher/graph_watcher.dart';
 import 'package:build_runner/src/watcher/node_watcher.dart';
 import 'package:build_runner_core/build_runner_core.dart';
 import 'package:build_runner_core/src/asset_graph/graph.dart';
 import 'package:build_runner_core/src/generate/build_impl.dart';
 import 'package:crypto/crypto.dart';
 import 'package:logging/logging.dart';
 import 'package:pedantic/pedantic.dart';
 import 'package:stream_transform/stream_transform.dart';
 import 'package:watcher/watcher.dart';

 import '../logging/std_io_logging.dart';
 import '../server/server.dart';
 import 'terminator.dart';

 final _logger = Logger('Watch');

 Future<ServeHandler> watch(
   List<BuilderApplication> builders, {
   bool deleteFilesByDefault,
   bool assumeTty,
   String configKey,
   PackageGraph packageGraph,
   RunnerAssetReader reader,
   RunnerAssetWriter writer,
   Resolvers resolvers,
   Level logLevel,
   onLog(LogRecord record),
   Duration debounceDelay,
   DirectoryWatcher Function(String) directoryWatcherFactory,
   Stream terminateEventStream,
   bool skipBuildScriptCheck,
   bool enableLowResourcesMode,
   Map<String, BuildConfig> overrideBuildConfig,
   Set<BuildDirectory> buildDirs,
   bool outputSymlinksOnly,
   bool trackPerformance,
   bool verbose,
   Map<String, Map<String, dynamic>> builderConfigOverrides,
   bool isReleaseBuild,
   String logPerformanceDir,
 }) async {
   builderConfigOverrides ??= const {};
   packageGraph ??= PackageGraph.forThisPackage();
   buildDirs ??= Set<BuildDirectory>();

   var environment = OverrideableEnvironment(
       IOEnvironment(packageGraph,
           assumeTty: assumeTty, outputSymlinksOnly: outputSymlinksOnly),
       reader: reader,
       writer: writer,
       onLog: onLog ?? stdIOLogListener(assumeTty: assumeTty, verbose: verbose));
   var logSubscription =
       LogSubscription(environment, verbose: verbose, logLevel: logLevel);
   overrideBuildConfig ??=
       await findBuildConfigOverrides(packageGraph, configKey);
   var options = await BuildOptions.create(
     logSubscription,
     deleteFilesByDefault: deleteFilesByDefault,
     packageGraph: packageGraph,
     overrideBuildConfig: overrideBuildConfig,
     debounceDelay: debounceDelay,
     skipBuildScriptCheck: skipBuildScriptCheck,
     enableLowResourcesMode: enableLowResourcesMode,
     trackPerformance: trackPerformance,
     logPerformanceDir: logPerformanceDir,
     resolvers: resolvers,
   );
   var terminator = Terminator(terminateEventStream);

   var watch = _runWatch(
       options,
       environment,
       builders,
       builderConfigOverrides,
       terminator.shouldTerminate,
       directoryWatcherFactory,
       configKey,
       buildDirs
           .any((target) => target?.outputLocation?.path?.isNotEmpty ?? false),
       buildDirs,
       isReleaseMode: isReleaseBuild ?? false);

   unawaited(watch.buildResults.drain().then((_) async {
     await terminator.cancel();
     await options.logListener.cancel();
   }));

   return createServeHandler(watch);
 }

 /// Repeatedly run builds as files change on disk until [until] fires.
 ///
 /// Sets up file watchers and collects changes then triggers new builds. When
 /// [until] fires the file watchers will be stopped and up to one additional
 /// build may run if there were pending changes.
 ///
 /// The [BuildState.buildResults] stream will end after the final build has been
 /// run.
 WatchImpl _runWatch(
         BuildOptions options,
         BuildEnvironment environment,
         List<BuilderApplication> builders,
         Map<String, Map<String, dynamic>> builderConfigOverrides,
         Future until,
         DirectoryWatcher Function(String) directoryWatcherFactory,
         String configKey,
         bool willCreateOutputDirs,
         Set<BuildDirectory> buildDirs,
         {bool isReleaseMode = false}) =>
     WatchImpl(options, environment, builders, builderConfigOverrides, until,
         directoryWatcherFactory, configKey, willCreateOutputDirs, buildDirs,
         isReleaseMode: isReleaseMode);

 class WatchImpl implements BuildState {
   BuildImpl _build;

   AssetGraph get assetGraph => _build?.assetGraph;

   final _readyCompleter = Completer<void>();
   Future<void> get ready => _readyCompleter.future;

   final String _configKey; // may be null

   /// Delay to wait for more file watcher events.
   final Duration _debounceDelay;

   /// Injectable factory for creating directory watchers.
   final DirectoryWatcher Function(String) _directoryWatcherFactory;

   /// Whether or not we will be creating any output directories.
   ///
   /// If not, then we don't care about source edits that don't have outputs.
   final bool _willCreateOutputDirs;

   /// Should complete when we need to kill the build.
   final _terminateCompleter = Completer<Null>();

   /// The [PackageGraph] for the current program.
   final PackageGraph packageGraph;

   /// The directories to build upon file changes and where to output them.
   final Set<BuildDirectory> _buildDirs;

   @override
   Future<BuildResult> currentBuild;

   /// Pending expected delete events from the build.
   final Set<AssetId> _expectedDeletes = Set<AssetId>();

   FinalizedReader _reader;
   FinalizedReader get reader => _reader;

   WatchImpl(
       BuildOptions options,
       BuildEnvironment environment,
       List<BuilderApplication> builders,
       Map<String, Map<String, dynamic>> builderConfigOverrides,
       Future until,
       this._directoryWatcherFactory,
       this._configKey,
       this._willCreateOutputDirs,
       this._buildDirs,
       {bool isReleaseMode = false})
       : _debounceDelay = options.debounceDelay,
         packageGraph = options.packageGraph {
     buildResults = _run(
             options, environment, builders, builderConfigOverrides, until,
             isReleaseMode: isReleaseMode)
         .asBroadcastStream();
   }

   @override
   Stream<BuildResult> buildResults;

   /// Runs a build any time relevant files change.
   ///
   /// Only one build will run at a time, and changes are batched.
   ///
   /// File watchers are scheduled synchronously.
   Stream<BuildResult> _run(
       BuildOptions options,
       BuildEnvironment environment,
       List<BuilderApplication> builders,
       Map<String, Map<String, dynamic>> builderConfigOverrides,
       Future until,
       {bool isReleaseMode = false}) {
     var watcherEnvironment = OverrideableEnvironment(environment,
         writer: OnDeleteWriter(environment.writer, _expectedDeletes.add));
     var firstBuildCompleter = Completer<BuildResult>();
     currentBuild = firstBuildCompleter.future;
     var controller = StreamController<BuildResult>();

     Future<BuildResult> doBuild(List<List<AssetChange>> changes) async {
       assert(_build != null);
       _logger..info('${'-' * 72}\n')..info('Starting Build\n');
       var mergedChanges = collectChanges(changes);

       _expectedDeletes.clear();
       if (!options.skipBuildScriptCheck) {
         if (_build.buildScriptUpdates
             .hasBeenUpdated(mergedChanges.keys.toSet())) {
           _terminateCompleter.complete();
           _logger.severe('Terminating builds due to build script update');
           return BuildResult(BuildStatus.failure, [],
               failureType: FailureType.buildScriptChanged);
         }
       }
       return _build.run(mergedChanges, buildDirs: _buildDirs);
     }

     var terminate = Future.any([until, _terminateCompleter.future]).then((_) {
       _logger.info('Terminating. No further builds will be scheduled\n');
     });

     Digest originalRootPackagesDigest;
     final rootPackagesId = AssetId(packageGraph.root.name, '.packages');

     // Start watching files immediately, before the first build is even started.
     var graphWatcher = PackageGraphWatcher(packageGraph,
         logger: _logger,
         watch: (node) =>
             PackageNodeWatcher(node, watch: _directoryWatcherFactory));
     graphWatcher
         .watch()
         .asyncMap<AssetChange>((change) {
           // Delay any events until the first build is completed.
           if (firstBuildCompleter.isCompleted) return change;
           return firstBuildCompleter.future.then((_) => change);
         })
         .asyncMap<AssetChange>((change) {
           var id = change.id;
           assert(originalRootPackagesDigest != null);
           if (id == rootPackagesId) {
             // Kill future builds if the root packages file changes.
             return watcherEnvironment.reader
                 .readAsBytes(rootPackagesId)
                 .then((bytes) {
               if (md5.convert(bytes) != originalRootPackagesDigest) {
                 _terminateCompleter.complete();
                 _logger
                     .severe('Terminating builds due to package graph update, '
                         'please restart the build.');
               }
               return change;
             });
           } else if (_isBuildYaml(id) ||
               _isConfiguredBuildYaml(id) ||
               _isPackageBuildYamlOverride(id)) {
             controller.add(BuildResult(BuildStatus.failure, [],
                 failureType: FailureType.buildConfigChanged));

             // Kill future builds if the build.yaml files change.
             _terminateCompleter.complete();
             _logger.severe(
                 'Terminating builds due to ${id.package}:${id.path} update.');
           }
           return change;
         })
         .where((change) {
           assert(_readyCompleter.isCompleted);
           return shouldProcess(
             change,
             assetGraph,
             options,
             _willCreateOutputDirs,
             _expectedDeletes,
           );
         })
         .transform(debounceBuffer(_debounceDelay))
         .transform(takeUntil(terminate))
         .transform(asyncMapBuffer((changes) => currentBuild = doBuild(changes)
           ..whenComplete(() => currentBuild = null)))
         .listen((BuildResult result) {
           if (controller.isClosed) return;
           controller.add(result);
         })
         .onDone(() async {
           await currentBuild;
           await _build?.beforeExit();
           if (!controller.isClosed) await controller.close();
           _logger.info('Builds finished. Safe to exit\n');
         });

     // Schedule the actual first build for the future so we can return the
     // stream synchronously.
     () async {
       await logTimedAsync(_logger, 'Waiting for all file watchers to be ready',
           () => graphWatcher.ready);
       originalRootPackagesDigest = md5
           .convert(await watcherEnvironment.reader.readAsBytes(rootPackagesId));

       BuildResult firstBuild;
       try {
         _build = await BuildImpl.create(
             options, watcherEnvironment, builders, builderConfigOverrides,
             isReleaseBuild: isReleaseMode);

         firstBuild = await _build.run({}, buildDirs: _buildDirs);
       } on CannotBuildException {
         _terminateCompleter.complete();

         firstBuild = BuildResult(BuildStatus.failure, []);
       } on BuildScriptChangedException {
         _terminateCompleter.complete();

         firstBuild = BuildResult(BuildStatus.failure, [],
             failureType: FailureType.buildScriptChanged);
       }

       _reader = _build?.finalizedReader;
       _readyCompleter.complete();
       // It is possible this is already closed if the user kills the process
       // early, which results in an exception without this check.
       if (!controller.isClosed) controller.add(firstBuild);
       firstBuildCompleter.complete(firstBuild);
     }();

     return controller.stream;
   }

   bool _isBuildYaml(AssetId id) => id.path == 'build.yaml';
   bool _isConfiguredBuildYaml(AssetId id) =>
       id.package == packageGraph.root.name &&
       id.path == 'build.$_configKey.yaml';
   bool _isPackageBuildYamlOverride(AssetId id) =>
       id.package == packageGraph.root.name &&
       id.path.contains(_packageBuildYamlRegexp);
   final _packageBuildYamlRegexp = RegExp(r'^[a-z0-9_]+\.build\.yaml$');
 }
	// Copyright (c) 2016, 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 'dart:async';

	import 'package:build/build.dart';
	import 'package:build_config/build_config.dart';
	import 'package:build_runner/src/package_graph/build_config_overrides.dart';
	import 'package:build_runner/src/watcher/asset_change.dart';
	import 'package:build_runner/src/watcher/change_filter.dart';
	import 'package:build_runner/src/watcher/collect_changes.dart';
	import 'package:build_runner/src/watcher/delete_writer.dart';
	import 'package:build_runner/src/watcher/graph_watcher.dart';
	import 'package:build_runner/src/watcher/node_watcher.dart';
	import 'package:build_runner_core/build_runner_core.dart';
	import 'package:build_runner_core/src/asset_graph/graph.dart';
	import 'package:build_runner_core/src/generate/build_impl.dart';
	import 'package:crypto/crypto.dart';
	import 'package:logging/logging.dart';
	import 'package:pedantic/pedantic.dart';
	import 'package:stream_transform/stream_transform.dart';
	import 'package:watcher/watcher.dart';

	import '../logging/std_io_logging.dart';
	import '../server/server.dart';
	import 'terminator.dart';

	final _logger = Logger('Watch');

	Future<ServeHandler> watch(
	List<BuilderApplication> builders, {
	bool deleteFilesByDefault,
	bool assumeTty,
	String configKey,
	PackageGraph packageGraph,
	RunnerAssetReader reader,
	RunnerAssetWriter writer,
	Resolvers resolvers,
	Level logLevel,
	onLog(LogRecord record),
	Duration debounceDelay,
	DirectoryWatcher Function(String) directoryWatcherFactory,
	Stream terminateEventStream,
	bool skipBuildScriptCheck,
	bool enableLowResourcesMode,
	Map<String, BuildConfig> overrideBuildConfig,
	Set<BuildDirectory> buildDirs,
	bool outputSymlinksOnly,
	bool trackPerformance,
	bool verbose,
	Map<String, Map<String, dynamic>> builderConfigOverrides,
	bool isReleaseBuild,
	String logPerformanceDir,
	}) async {
	builderConfigOverrides ??= const {};
	packageGraph ??= PackageGraph.forThisPackage();
	buildDirs ??= Set<BuildDirectory>();

	var environment = OverrideableEnvironment(
	IOEnvironment(packageGraph,
	assumeTty: assumeTty, outputSymlinksOnly: outputSymlinksOnly),
	reader: reader,
	writer: writer,
	onLog: onLog ?? stdIOLogListener(assumeTty: assumeTty, verbose: verbose));
	var logSubscription =
	LogSubscription(environment, verbose: verbose, logLevel: logLevel);
	overrideBuildConfig ??=
	await findBuildConfigOverrides(packageGraph, configKey);
	var options = await BuildOptions.create(
	logSubscription,
	deleteFilesByDefault: deleteFilesByDefault,
	packageGraph: packageGraph,
	overrideBuildConfig: overrideBuildConfig,
	debounceDelay: debounceDelay,
	skipBuildScriptCheck: skipBuildScriptCheck,
	enableLowResourcesMode: enableLowResourcesMode,
	trackPerformance: trackPerformance,
	logPerformanceDir: logPerformanceDir,
	resolvers: resolvers,
	);
	var terminator = Terminator(terminateEventStream);

	var watch = _runWatch(
	options,
	environment,
	builders,
	builderConfigOverrides,
	terminator.shouldTerminate,
	directoryWatcherFactory,
	configKey,
	buildDirs
	.any((target) => target?.outputLocation?.path?.isNotEmpty ?? false),
	buildDirs,
	isReleaseMode: isReleaseBuild ?? false);

	unawaited(watch.buildResults.drain().then((_) async {
	await terminator.cancel();
	await options.logListener.cancel();
	}));

	return createServeHandler(watch);
	}

	/// Repeatedly run builds as files change on disk until [until] fires.
	///
	/// Sets up file watchers and collects changes then triggers new builds. When
	/// [until] fires the file watchers will be stopped and up to one additional
	/// build may run if there were pending changes.
	///
	/// The [BuildState.buildResults] stream will end after the final build has been
	/// run.
	WatchImpl _runWatch(
	BuildOptions options,
	BuildEnvironment environment,
	List<BuilderApplication> builders,
	Map<String, Map<String, dynamic>> builderConfigOverrides,
	Future until,
	DirectoryWatcher Function(String) directoryWatcherFactory,
	String configKey,
	bool willCreateOutputDirs,
	Set<BuildDirectory> buildDirs,
	{bool isReleaseMode = false}) =>
	WatchImpl(options, environment, builders, builderConfigOverrides, until,
	directoryWatcherFactory, configKey, willCreateOutputDirs, buildDirs,
	isReleaseMode: isReleaseMode);

	class WatchImpl implements BuildState {
	BuildImpl _build;

	AssetGraph get assetGraph => _build?.assetGraph;

	final _readyCompleter = Completer<void>();
	Future<void> get ready => _readyCompleter.future;

	final String _configKey; // may be null

	/// Delay to wait for more file watcher events.
	final Duration _debounceDelay;

	/// Injectable factory for creating directory watchers.
	final DirectoryWatcher Function(String) _directoryWatcherFactory;

	/// Whether or not we will be creating any output directories.
	///
	/// If not, then we don't care about source edits that don't have outputs.
	final bool _willCreateOutputDirs;

	/// Should complete when we need to kill the build.
	final _terminateCompleter = Completer<Null>();

	/// The [PackageGraph] for the current program.
	final PackageGraph packageGraph;

	/// The directories to build upon file changes and where to output them.
	final Set<BuildDirectory> _buildDirs;

	@override
	Future<BuildResult> currentBuild;

	/// Pending expected delete events from the build.
	final Set<AssetId> _expectedDeletes = Set<AssetId>();

	FinalizedReader _reader;
	FinalizedReader get reader => _reader;

	WatchImpl(
	BuildOptions options,
	BuildEnvironment environment,
	List<BuilderApplication> builders,
	Map<String, Map<String, dynamic>> builderConfigOverrides,
	Future until,
	this._directoryWatcherFactory,
	this._configKey,
	this._willCreateOutputDirs,
	this._buildDirs,
	{bool isReleaseMode = false})
	: _debounceDelay = options.debounceDelay,
	packageGraph = options.packageGraph {
	buildResults = _run(
	options, environment, builders, builderConfigOverrides, until,
	isReleaseMode: isReleaseMode)
	.asBroadcastStream();
	}

	@override
	Stream<BuildResult> buildResults;

	/// Runs a build any time relevant files change.
	///
	/// Only one build will run at a time, and changes are batched.
	///
	/// File watchers are scheduled synchronously.
	Stream<BuildResult> _run(
	BuildOptions options,
	BuildEnvironment environment,
	List<BuilderApplication> builders,
	Map<String, Map<String, dynamic>> builderConfigOverrides,
	Future until,
	{bool isReleaseMode = false}) {
	var watcherEnvironment = OverrideableEnvironment(environment,
	writer: OnDeleteWriter(environment.writer, _expectedDeletes.add));
	var firstBuildCompleter = Completer<BuildResult>();
	currentBuild = firstBuildCompleter.future;
	var controller = StreamController<BuildResult>();

	Future<BuildResult> doBuild(List<List<AssetChange>> changes) async {
	assert(_build != null);
	_logger..info('${'-' * 72}\n')..info('Starting Build\n');
	var mergedChanges = collectChanges(changes);

	_expectedDeletes.clear();
	if (!options.skipBuildScriptCheck) {
	if (_build.buildScriptUpdates
	.hasBeenUpdated(mergedChanges.keys.toSet())) {
	_terminateCompleter.complete();
	_logger.severe('Terminating builds due to build script update');
	return BuildResult(BuildStatus.failure, [],
	failureType: FailureType.buildScriptChanged);
	}
	}
	return _build.run(mergedChanges, buildDirs: _buildDirs);
	}

	var terminate = Future.any([until, _terminateCompleter.future]).then((_) {
	_logger.info('Terminating. No further builds will be scheduled\n');
	});

	Digest originalRootPackagesDigest;
	final rootPackagesId = AssetId(packageGraph.root.name, '.packages');

	// Start watching files immediately, before the first build is even started.
	var graphWatcher = PackageGraphWatcher(packageGraph,
	logger: _logger,
	watch: (node) =>
	PackageNodeWatcher(node, watch: _directoryWatcherFactory));
	graphWatcher
	.watch()
	.asyncMap<AssetChange>((change) {
	// Delay any events until the first build is completed.
	if (firstBuildCompleter.isCompleted) return change;
	return firstBuildCompleter.future.then((_) => change);
	})
	.asyncMap<AssetChange>((change) {
	var id = change.id;
	assert(originalRootPackagesDigest != null);
	if (id == rootPackagesId) {
	// Kill future builds if the root packages file changes.
	return watcherEnvironment.reader
	.readAsBytes(rootPackagesId)
	.then((bytes) {
	if (md5.convert(bytes) != originalRootPackagesDigest) {
	_terminateCompleter.complete();
	_logger
	.severe('Terminating builds due to package graph update, '
	'please restart the build.');
	}
	return change;
	});
	} else if (_isBuildYaml(id) \|\|
	_isConfiguredBuildYaml(id) \|\|
	_isPackageBuildYamlOverride(id)) {
	controller.add(BuildResult(BuildStatus.failure, [],
	failureType: FailureType.buildConfigChanged));

	// Kill future builds if the build.yaml files change.
	_terminateCompleter.complete();
	_logger.severe(
	'Terminating builds due to ${id.package}:${id.path} update.');
	}
	return change;
	})
	.where((change) {
	assert(_readyCompleter.isCompleted);
	return shouldProcess(
	change,
	assetGraph,
	options,
	_willCreateOutputDirs,
	_expectedDeletes,
	);
	})
	.transform(debounceBuffer(_debounceDelay))
	.transform(takeUntil(terminate))
	.transform(asyncMapBuffer((changes) => currentBuild = doBuild(changes)
	..whenComplete(() => currentBuild = null)))
	.listen((BuildResult result) {
	if (controller.isClosed) return;
	controller.add(result);
	})
	.onDone(() async {
	await currentBuild;
	await _build?.beforeExit();
	if (!controller.isClosed) await controller.close();
	_logger.info('Builds finished. Safe to exit\n');
	});

	// Schedule the actual first build for the future so we can return the
	// stream synchronously.
	() async {
	await logTimedAsync(_logger, 'Waiting for all file watchers to be ready',
	() => graphWatcher.ready);
	originalRootPackagesDigest = md5
	.convert(await watcherEnvironment.reader.readAsBytes(rootPackagesId));

	BuildResult firstBuild;
	try {
	_build = await BuildImpl.create(
	options, watcherEnvironment, builders, builderConfigOverrides,
	isReleaseBuild: isReleaseMode);

	firstBuild = await _build.run({}, buildDirs: _buildDirs);
	} on CannotBuildException {
	_terminateCompleter.complete();

	firstBuild = BuildResult(BuildStatus.failure, []);
	} on BuildScriptChangedException {
	_terminateCompleter.complete();

	firstBuild = BuildResult(BuildStatus.failure, [],
	failureType: FailureType.buildScriptChanged);
	}

	_reader = _build?.finalizedReader;
	_readyCompleter.complete();
	// It is possible this is already closed if the user kills the process
	// early, which results in an exception without this check.
	if (!controller.isClosed) controller.add(firstBuild);
	firstBuildCompleter.complete(firstBuild);
	}();

	return controller.stream;
	}

	bool _isBuildYaml(AssetId id) => id.path == 'build.yaml';
	bool _isConfiguredBuildYaml(AssetId id) =>
	id.package == packageGraph.root.name &&
	id.path == 'build.$_configKey.yaml';
	bool _isPackageBuildYamlOverride(AssetId id) =>
	id.package == packageGraph.root.name &&
	id.path.contains(_packageBuildYamlRegexp);
	final _packageBuildYamlRegexp = RegExp(r'^[a-z0-9_]+\.build\.yaml$');
	}