pkg/polymer/lib/src/build/runner.dart - sdk.git - Git at Google

 // 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.

 /// Definitions used to run the polymer linter and deploy tools without using
 /// pub serve or pub deploy.
 library polymer.src.build.runner;

 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';

 import 'package:barback/barback.dart';
 import 'package:path/path.dart' as path;
 import 'package:stack_trace/stack_trace.dart';
 import 'package:yaml/yaml.dart';


 /// Collects different parameters needed to configure and run barback.
 class BarbackOptions {
   /// Phases of transformers to run for the current package.
   /// Use packagePhases to specify phases for other packages.
   final List<List<Transformer>> phases;

   /// Package to treat as the current package in barback.
   final String currentPackage;

   /// Directory root for the current package.
   final String packageHome;

   /// Mapping between package names and the path in the file system where
   /// to find the sources of such package.
   final Map<String, String> packageDirs;

   /// Whether to run transformers on the test folder.
   final bool transformTests;

   /// Directory where to generate code, if any.
   final String outDir;

   /// Disregard files that match these filters when copying in non
   /// transformed files
   List<String> fileFilter;

   /// Whether to print error messages using a json-format that tools, such as
   /// the Dart Editor, can process.
   final bool machineFormat;

   /// Whether to follow symlinks when listing directories. By default this is
   /// false because directories have symlinks for the packages directory created
   /// by pub, but it can be turned on for custom uses of this library.
   final bool followLinks;

   /// Phases of transformers to apply to packages other than the current
   /// package, keyed by the package name.
   final Map<String, List<List<Transformer>>> packagePhases;

   BarbackOptions(this.phases, this.outDir, {currentPackage, String packageHome,
       packageDirs, this.transformTests: false, this.machineFormat: false,
       this.followLinks: false,
       this.packagePhases: const {},
       this.fileFilter: const []})
       : currentPackage = (currentPackage != null
           ? currentPackage : readCurrentPackageFromPubspec()),
         packageHome = packageHome,
         packageDirs = (packageDirs != null
           ? packageDirs : readPackageDirsFromPub(packageHome, currentPackage));

 }

 /// Creates a barback system as specified by [options] and runs it.  Returns a
 /// future that contains the list of assets generated after barback runs to
 /// completion.
 Future<AssetSet> runBarback(BarbackOptions options) {
   var barback = new Barback(new _PackageProvider(options.packageDirs));
   _initBarback(barback, options);
   _attachListeners(barback, options);
   if (options.outDir == null) return barback.getAllAssets();
   return _emitAllFiles(barback, options);
 }

 /// Extract the current package from the pubspec.yaml file.
 String readCurrentPackageFromPubspec([String dir]) {
   var pubspec = new File(
       dir == null ? 'pubspec.yaml' : path.join(dir, 'pubspec.yaml'));
   if (!pubspec.existsSync()) {
     print('error: pubspec.yaml file not found, please run this script from '
         'your package root directory.');
     return null;
   }
   return loadYaml(pubspec.readAsStringSync())['name'];
 }

 /// Extract a mapping between package names and the path in the file system
 /// which has the source of the package. This map will contain an entry for the
 /// current package and everything it depends on (extracted via `pub
 /// list-package-dirs`).
 Map<String, String> readPackageDirsFromPub(
     [String packageHome, String currentPackage]) {
   var cachedDir = Directory.current;
   if (packageHome != null) {
     Directory.current = new Directory(packageHome);
   } else {
     packageHome = cachedDir.path;
   }

   var dartExec = Platform.executable;
   // If dartExec == dart, then dart and pub are in standard PATH.
   var sdkDir = dartExec == 'dart' ? '' : path.dirname(dartExec);
   var pub = path.join(sdkDir, Platform.isWindows ? 'pub.bat' : 'pub');
   var result = Process.runSync(pub, ['list-package-dirs']);
   if (result.exitCode != 0) {
     print("unexpected error invoking 'pub':");
     print(result.stdout);
     print(result.stderr);
     exit(result.exitCode);
   }
   var map = JSON.decode(result.stdout)["packages"];
   map.forEach((k, v) { map[k] = path.absolute(packageHome, path.dirname(v)); });

   if (currentPackage == null) {
     currentPackage = readCurrentPackageFromPubspec(packageHome);
   }
   map[currentPackage] = packageHome;

   Directory.current = cachedDir;
   return map;
 }

 bool shouldSkip(List<String> filters, String path) {
   return filters.any((filter) => path.contains(filter));
 }

 /// Return the relative path of each file under [subDir] in [package].
 Iterable<String> _listPackageDir(String package, String subDir,
     BarbackOptions options) {
   var packageDir = options.packageDirs[package];
   if (packageDir == null) return const [];
   var dir = new Directory(path.join(packageDir, subDir));
   if (!dir.existsSync()) return const [];
   return dir.listSync(recursive: true, followLinks: options.followLinks)
       .where((f) => f is File)
       .where((f) => !shouldSkip(options.fileFilter, f.path))
       .map((f) => path.relative(f.path, from: packageDir));
 }

 /// A simple provider that reads files directly from the pub cache.
 class _PackageProvider implements PackageProvider {
   Map<String, String> packageDirs;
   Iterable<String> get packages => packageDirs.keys;

   _PackageProvider(this.packageDirs);

   Future<Asset> getAsset(AssetId id) => new Future.value(
       new Asset.fromPath(id, path.join(packageDirs[id.package],
       _toSystemPath(id.path))));
 }

 /// Convert asset paths to system paths (Assets always use the posix style).
 String _toSystemPath(String assetPath) {
   if (path.Style.platform != path.Style.windows) return assetPath;
   return path.joinAll(path.posix.split(assetPath));
 }

 /// Tell barback which transformers to use and which assets to process.
 void _initBarback(Barback barback, BarbackOptions options) {
   var assets = [];
   void addAssets(String package, String subDir) {
     for (var filepath in _listPackageDir(package, subDir, options)) {
       assets.add(new AssetId(package, filepath));
     }
   }

   for (var package in options.packageDirs.keys) {
     // Notify barback to process anything under 'lib' and 'asset'.
     addAssets(package, 'lib');
     addAssets(package, 'asset');

     if (options.packagePhases.containsKey(package)) {
       barback.updateTransformers(package, options.packagePhases[package]);
     }
   }
   barback.updateTransformers(options.currentPackage, options.phases);

   // In case of the current package, include also 'web'.
   addAssets(options.currentPackage, 'web');
   if (options.transformTests) addAssets(options.currentPackage, 'test');

   // Add the sources after the transformers so all transformers are present
   // when barback starts processing the assets.
   barback.updateSources(assets);
 }

 /// Attach error listeners on [barback] so we can report errors.
 void _attachListeners(Barback barback, BarbackOptions options) {
   // Listen for errors and results
   barback.errors.listen((e) {
     var trace = null;
     if (e is Error) trace = e.stackTrace;
     if (trace != null) {
       print(Trace.format(trace));
     }
     print('error running barback: $e');
     exit(1);
   });

   barback.results.listen((result) {
     if (!result.succeeded) {
       print("build failed with errors: ${result.errors}");
       exit(1);
     }
   });

   barback.log.listen((entry) {
     if (options.machineFormat) {
       print(_jsonFormatter(entry));
     } else {
       print(_consoleFormatter(entry));
     }
   });
 }

 /// Emits all outputs of [barback] and copies files that we didn't process (like
 /// dependent package's libraries).
 Future _emitAllFiles(Barback barback, BarbackOptions options) {
   return barback.getAllAssets().then((assets) {
     // Delete existing output folder before we generate anything
     var dir = new Directory(options.outDir);
     if (dir.existsSync()) dir.deleteSync(recursive: true);
     return _emitPackagesDir(options)
       .then((_) => _emitTransformedFiles(assets, options))
       .then((_) => _addPackagesSymlinks(assets, options))
       .then((_) => assets);
   });
 }

 Future _emitTransformedFiles(AssetSet assets, BarbackOptions options) {
   // Copy all the assets we transformed
   var futures = [];
   var currentPackage = options.currentPackage;
   var transformTests = options.transformTests;
   var outPackages = path.join(options.outDir, 'packages');

   return Future.forEach(assets, (asset) {
     var id = asset.id;
     var dir = _firstDir(id.path);
     if (dir == null) return null;

     var filepath;
     if (dir == 'lib') {
       // Put lib files directly under the packages folder (e.g. 'lib/foo.dart'
       // will be emitted at out/packages/package_name/foo.dart).
       filepath = path.join(outPackages, id.package,
           _toSystemPath(id.path.substring(4)));
     } else if (id.package == currentPackage &&
         (dir == 'web' || (transformTests && dir == 'test'))) {
       filepath = path.join(options.outDir, _toSystemPath(id.path));
     } else {
       // TODO(sigmund): do something about other assets?
       return null;
     }

     return _writeAsset(filepath, asset);
   });
 }

 /// Adds a package symlink from each directory under `out/web/foo/` to
 /// `out/packages`.
 void _addPackagesSymlinks(AssetSet assets, BarbackOptions options) {
   var outPackages = path.join(options.outDir, 'packages');
   var currentPackage = options.currentPackage;
   for (var asset in assets) {
     var id = asset.id;
     if (id.package != currentPackage) continue;
     var firstDir = _firstDir(id.path);
     if (firstDir == null) continue;

     if (firstDir == 'web' || (options.transformTests && firstDir == 'test')) {
       var dir = path.join(options.outDir, path.dirname(_toSystemPath(id.path)));
       var linkPath = path.join(dir, 'packages');
       var link = new Link(linkPath);
       if (!link.existsSync()) {
         var targetPath = Platform.operatingSystem == 'windows'
             ? path.normalize(path.absolute(outPackages))
             : path.normalize(path.relative(outPackages, from: dir));
         link.createSync(targetPath);
       }
     }
   }
 }

 /// Emits a 'packages' directory directly under `out/packages` with the contents
 /// of every file that was not transformed by barback.
 Future _emitPackagesDir(BarbackOptions options) {
   var outPackages = path.join(options.outDir, 'packages');
   _ensureDir(outPackages);

   // Copy all the files we didn't process
   var dirs = options.packageDirs;
   return Future.forEach(dirs.keys, (package) {
     return Future.forEach(_listPackageDir(package, 'lib', options), (relpath) {
       var inpath = path.join(dirs[package], relpath);
       var outpath = path.join(outPackages, package, relpath.substring(4));
       return _copyFile(inpath, outpath);
     });
   });
 }

 /// Ensure [dirpath] exists.
 void _ensureDir(String dirpath) {
   new Directory(dirpath).createSync(recursive: true);
 }

 /// Returns the first directory name on a url-style path, or null if there are
 /// no slashes.
 String _firstDir(String url) {
   var firstSlash = url.indexOf('/');
   if (firstSlash == -1) return null;
   return url.substring(0, firstSlash);
 }

 /// Copy a file from [inpath] to [outpath].
 Future _copyFile(String inpath, String outpath) {
   _ensureDir(path.dirname(outpath));
   return new File(inpath).openRead().pipe(new File(outpath).openWrite());
 }

 /// Write contents of an [asset] into a file at [filepath].
 Future _writeAsset(String filepath, Asset asset) {
   _ensureDir(path.dirname(filepath));
   return asset.read().pipe(new File(filepath).openWrite());
 }

 String _kindFromEntry(LogEntry entry) {
   var level = entry.level;
   return level == LogLevel.ERROR ? 'error'
       : (level == LogLevel.WARNING ? 'warning' : 'info');
 }

 /// Formatter that generates messages using a format that can be parsed
 /// by tools, such as the Dart Editor, for reporting error messages.
 String _jsonFormatter(LogEntry entry) {
   var kind = _kindFromEntry(entry);
   var span = entry.span;
   return JSON.encode((span == null)
       ? [{'method': kind, 'params': {'message': entry.message}}]
       : [{'method': kind,
           'params': {
             'file': span.sourceUrl.toString(),
             'message': entry.message,
             'line': span.start.line + 1,
             'charStart': span.start.offset,
             'charEnd': span.end.offset,
           }}]);
 }

 /// Formatter that generates messages that are easy to read on the console (used
 /// by default).
 String _consoleFormatter(LogEntry entry) {
   var kind = _kindFromEntry(entry);
   var useColors = stdioType(stdout) == StdioType.TERMINAL;
   var levelColor = (kind == 'error') ? _RED_COLOR : _MAGENTA_COLOR;
   var output = new StringBuffer();
   if (useColors) output.write(levelColor);
   output..write(kind)..write(' ');
   if (useColors) output.write(_NO_COLOR);
   if (entry.span == null) {
     output.write(entry.message);
   } else {
     output.write(entry.span.message(entry.message,
           color: useColors ? levelColor : null));
   }
   return output.toString();
 }

 const String _RED_COLOR = '\u001b[31m';
 const String _MAGENTA_COLOR = '\u001b[35m';
 const String _NO_COLOR = '\u001b[0m';
	// 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.

	/// Definitions used to run the polymer linter and deploy tools without using
	/// pub serve or pub deploy.
	library polymer.src.build.runner;

	import 'dart:async';
	import 'dart:convert';
	import 'dart:io';

	import 'package:barback/barback.dart';
	import 'package:path/path.dart' as path;
	import 'package:stack_trace/stack_trace.dart';
	import 'package:yaml/yaml.dart';


	/// Collects different parameters needed to configure and run barback.
	class BarbackOptions {
	/// Phases of transformers to run for the current package.
	/// Use packagePhases to specify phases for other packages.
	final List<List<Transformer>> phases;

	/// Package to treat as the current package in barback.
	final String currentPackage;

	/// Directory root for the current package.
	final String packageHome;

	/// Mapping between package names and the path in the file system where
	/// to find the sources of such package.
	final Map<String, String> packageDirs;

	/// Whether to run transformers on the test folder.
	final bool transformTests;

	/// Directory where to generate code, if any.
	final String outDir;

	/// Disregard files that match these filters when copying in non
	/// transformed files
	List<String> fileFilter;

	/// Whether to print error messages using a json-format that tools, such as
	/// the Dart Editor, can process.
	final bool machineFormat;

	/// Whether to follow symlinks when listing directories. By default this is
	/// false because directories have symlinks for the packages directory created
	/// by pub, but it can be turned on for custom uses of this library.
	final bool followLinks;

	/// Phases of transformers to apply to packages other than the current
	/// package, keyed by the package name.
	final Map<String, List<List<Transformer>>> packagePhases;

	BarbackOptions(this.phases, this.outDir, {currentPackage, String packageHome,
	packageDirs, this.transformTests: false, this.machineFormat: false,
	this.followLinks: false,
	this.packagePhases: const {},
	this.fileFilter: const []})
	: currentPackage = (currentPackage != null
	? currentPackage : readCurrentPackageFromPubspec()),
	packageHome = packageHome,
	packageDirs = (packageDirs != null
	? packageDirs : readPackageDirsFromPub(packageHome, currentPackage));

	}

	/// Creates a barback system as specified by [options] and runs it. Returns a
	/// future that contains the list of assets generated after barback runs to
	/// completion.
	Future<AssetSet> runBarback(BarbackOptions options) {
	var barback = new Barback(new _PackageProvider(options.packageDirs));
	_initBarback(barback, options);
	_attachListeners(barback, options);
	if (options.outDir == null) return barback.getAllAssets();
	return _emitAllFiles(barback, options);
	}

	/// Extract the current package from the pubspec.yaml file.
	String readCurrentPackageFromPubspec([String dir]) {
	var pubspec = new File(
	dir == null ? 'pubspec.yaml' : path.join(dir, 'pubspec.yaml'));
	if (!pubspec.existsSync()) {
	print('error: pubspec.yaml file not found, please run this script from '
	'your package root directory.');
	return null;
	}
	return loadYaml(pubspec.readAsStringSync())['name'];
	}

	/// Extract a mapping between package names and the path in the file system
	/// which has the source of the package. This map will contain an entry for the
	/// current package and everything it depends on (extracted via `pub
	/// list-package-dirs`).
	Map<String, String> readPackageDirsFromPub(
	[String packageHome, String currentPackage]) {
	var cachedDir = Directory.current;
	if (packageHome != null) {
	Directory.current = new Directory(packageHome);
	} else {
	packageHome = cachedDir.path;
	}

	var dartExec = Platform.executable;
	// If dartExec == dart, then dart and pub are in standard PATH.
	var sdkDir = dartExec == 'dart' ? '' : path.dirname(dartExec);
	var pub = path.join(sdkDir, Platform.isWindows ? 'pub.bat' : 'pub');
	var result = Process.runSync(pub, ['list-package-dirs']);
	if (result.exitCode != 0) {
	print("unexpected error invoking 'pub':");
	print(result.stdout);
	print(result.stderr);
	exit(result.exitCode);
	}
	var map = JSON.decode(result.stdout)["packages"];
	map.forEach((k, v) { map[k] = path.absolute(packageHome, path.dirname(v)); });

	if (currentPackage == null) {
	currentPackage = readCurrentPackageFromPubspec(packageHome);
	}
	map[currentPackage] = packageHome;

	Directory.current = cachedDir;
	return map;
	}

	bool shouldSkip(List<String> filters, String path) {
	return filters.any((filter) => path.contains(filter));
	}

	/// Return the relative path of each file under [subDir] in [package].
	Iterable<String> _listPackageDir(String package, String subDir,
	BarbackOptions options) {
	var packageDir = options.packageDirs[package];
	if (packageDir == null) return const [];
	var dir = new Directory(path.join(packageDir, subDir));
	if (!dir.existsSync()) return const [];
	return dir.listSync(recursive: true, followLinks: options.followLinks)
	.where((f) => f is File)
	.where((f) => !shouldSkip(options.fileFilter, f.path))
	.map((f) => path.relative(f.path, from: packageDir));
	}

	/// A simple provider that reads files directly from the pub cache.
	class _PackageProvider implements PackageProvider {
	Map<String, String> packageDirs;
	Iterable<String> get packages => packageDirs.keys;

	_PackageProvider(this.packageDirs);

	Future<Asset> getAsset(AssetId id) => new Future.value(
	new Asset.fromPath(id, path.join(packageDirs[id.package],
	_toSystemPath(id.path))));
	}

	/// Convert asset paths to system paths (Assets always use the posix style).
	String _toSystemPath(String assetPath) {
	if (path.Style.platform != path.Style.windows) return assetPath;
	return path.joinAll(path.posix.split(assetPath));
	}

	/// Tell barback which transformers to use and which assets to process.
	void _initBarback(Barback barback, BarbackOptions options) {
	var assets = [];
	void addAssets(String package, String subDir) {
	for (var filepath in _listPackageDir(package, subDir, options)) {
	assets.add(new AssetId(package, filepath));
	}
	}

	for (var package in options.packageDirs.keys) {
	// Notify barback to process anything under 'lib' and 'asset'.
	addAssets(package, 'lib');
	addAssets(package, 'asset');

	if (options.packagePhases.containsKey(package)) {
	barback.updateTransformers(package, options.packagePhases[package]);
	}
	}
	barback.updateTransformers(options.currentPackage, options.phases);

	// In case of the current package, include also 'web'.
	addAssets(options.currentPackage, 'web');
	if (options.transformTests) addAssets(options.currentPackage, 'test');

	// Add the sources after the transformers so all transformers are present
	// when barback starts processing the assets.
	barback.updateSources(assets);
	}

	/// Attach error listeners on [barback] so we can report errors.
	void _attachListeners(Barback barback, BarbackOptions options) {
	// Listen for errors and results
	barback.errors.listen((e) {
	var trace = null;
	if (e is Error) trace = e.stackTrace;
	if (trace != null) {
	print(Trace.format(trace));
	}
	print('error running barback: $e');
	exit(1);
	});

	barback.results.listen((result) {
	if (!result.succeeded) {
	print("build failed with errors: ${result.errors}");
	exit(1);
	}
	});

	barback.log.listen((entry) {
	if (options.machineFormat) {
	print(_jsonFormatter(entry));
	} else {
	print(_consoleFormatter(entry));
	}
	});
	}

	/// Emits all outputs of [barback] and copies files that we didn't process (like
	/// dependent package's libraries).
	Future _emitAllFiles(Barback barback, BarbackOptions options) {
	return barback.getAllAssets().then((assets) {
	// Delete existing output folder before we generate anything
	var dir = new Directory(options.outDir);
	if (dir.existsSync()) dir.deleteSync(recursive: true);
	return _emitPackagesDir(options)
	.then((_) => _emitTransformedFiles(assets, options))
	.then((_) => _addPackagesSymlinks(assets, options))
	.then((_) => assets);
	});
	}

	Future _emitTransformedFiles(AssetSet assets, BarbackOptions options) {
	// Copy all the assets we transformed
	var futures = [];
	var currentPackage = options.currentPackage;
	var transformTests = options.transformTests;
	var outPackages = path.join(options.outDir, 'packages');

	return Future.forEach(assets, (asset) {
	var id = asset.id;
	var dir = _firstDir(id.path);
	if (dir == null) return null;

	var filepath;
	if (dir == 'lib') {
	// Put lib files directly under the packages folder (e.g. 'lib/foo.dart'
	// will be emitted at out/packages/package_name/foo.dart).
	filepath = path.join(outPackages, id.package,
	_toSystemPath(id.path.substring(4)));
	} else if (id.package == currentPackage &&
	(dir == 'web' \|\| (transformTests && dir == 'test'))) {
	filepath = path.join(options.outDir, _toSystemPath(id.path));
	} else {
	// TODO(sigmund): do something about other assets?
	return null;
	}

	return _writeAsset(filepath, asset);
	});
	}

	/// Adds a package symlink from each directory under `out/web/foo/` to
	/// `out/packages`.
	void _addPackagesSymlinks(AssetSet assets, BarbackOptions options) {
	var outPackages = path.join(options.outDir, 'packages');
	var currentPackage = options.currentPackage;
	for (var asset in assets) {
	var id = asset.id;
	if (id.package != currentPackage) continue;
	var firstDir = _firstDir(id.path);
	if (firstDir == null) continue;

	if (firstDir == 'web' \|\| (options.transformTests && firstDir == 'test')) {
	var dir = path.join(options.outDir, path.dirname(_toSystemPath(id.path)));
	var linkPath = path.join(dir, 'packages');
	var link = new Link(linkPath);
	if (!link.existsSync()) {
	var targetPath = Platform.operatingSystem == 'windows'
	? path.normalize(path.absolute(outPackages))
	: path.normalize(path.relative(outPackages, from: dir));
	link.createSync(targetPath);
	}
	}
	}
	}

	/// Emits a 'packages' directory directly under `out/packages` with the contents
	/// of every file that was not transformed by barback.
	Future _emitPackagesDir(BarbackOptions options) {
	var outPackages = path.join(options.outDir, 'packages');
	_ensureDir(outPackages);

	// Copy all the files we didn't process
	var dirs = options.packageDirs;
	return Future.forEach(dirs.keys, (package) {
	return Future.forEach(_listPackageDir(package, 'lib', options), (relpath) {
	var inpath = path.join(dirs[package], relpath);
	var outpath = path.join(outPackages, package, relpath.substring(4));
	return _copyFile(inpath, outpath);
	});
	});
	}

	/// Ensure [dirpath] exists.
	void _ensureDir(String dirpath) {
	new Directory(dirpath).createSync(recursive: true);
	}

	/// Returns the first directory name on a url-style path, or null if there are
	/// no slashes.
	String _firstDir(String url) {
	var firstSlash = url.indexOf('/');
	if (firstSlash == -1) return null;
	return url.substring(0, firstSlash);
	}

	/// Copy a file from [inpath] to [outpath].
	Future _copyFile(String inpath, String outpath) {
	_ensureDir(path.dirname(outpath));
	return new File(inpath).openRead().pipe(new File(outpath).openWrite());
	}

	/// Write contents of an [asset] into a file at [filepath].
	Future _writeAsset(String filepath, Asset asset) {
	_ensureDir(path.dirname(filepath));
	return asset.read().pipe(new File(filepath).openWrite());
	}

	String _kindFromEntry(LogEntry entry) {
	var level = entry.level;
	return level == LogLevel.ERROR ? 'error'
	: (level == LogLevel.WARNING ? 'warning' : 'info');
	}

	/// Formatter that generates messages using a format that can be parsed
	/// by tools, such as the Dart Editor, for reporting error messages.
	String _jsonFormatter(LogEntry entry) {
	var kind = _kindFromEntry(entry);
	var span = entry.span;
	return JSON.encode((span == null)
	? [{'method': kind, 'params': {'message': entry.message}}]
	: [{'method': kind,
	'params': {
	'file': span.sourceUrl.toString(),
	'message': entry.message,
	'line': span.start.line + 1,
	'charStart': span.start.offset,
	'charEnd': span.end.offset,
	}}]);
	}

	/// Formatter that generates messages that are easy to read on the console (used
	/// by default).
	String _consoleFormatter(LogEntry entry) {
	var kind = _kindFromEntry(entry);
	var useColors = stdioType(stdout) == StdioType.TERMINAL;
	var levelColor = (kind == 'error') ? _RED_COLOR : _MAGENTA_COLOR;
	var output = new StringBuffer();
	if (useColors) output.write(levelColor);
	output..write(kind)..write(' ');
	if (useColors) output.write(_NO_COLOR);
	if (entry.span == null) {
	output.write(entry.message);
	} else {
	output.write(entry.span.message(entry.message,
	color: useColors ? levelColor : null));
	}
	return output.toString();
	}

	const String _RED_COLOR = '\u001b[31m';
	const String _MAGENTA_COLOR = '\u001b[35m';
	const String _NO_COLOR = '\u001b[0m';