Remove webdev dependency from dwds (#486)

Towards #475

No longer depend on webdev for building and serving, instead create a simple test server and make use of the build daemon.

Author: grouma

_test/pubspec.yaml

@@ -15,9 +15,3 @@ dependencies:
 dev_dependencies:
   build_runner: ^1.0.0
   build_web_compilers: '>=1.0.0 <3.0.0'
-
-dependency_overrides:
-  webdev:
-    path: ../webdev
-  dwds:
-    path: ../dwds

dwds/pubspec.yaml

@@ -18,6 +18,7 @@ dependencies:
   pedantic: ^1.5.0
   pub_semver: ^1.4.2
   shelf: ^0.7.0
+  shelf_proxy: ^0.1.0+6
   shelf_web_socket: ^0.2.0
   source_maps: ^0.10.0
   vm_service_lib: 3.20.0+02
@@ -31,11 +32,7 @@ dev_dependencies:
   built_value_generator: ^6.4.0
   graphs: ^0.2.0
   js: ^0.6.1
+  sse: ^2.0.2
   test: ^1.6.0
   uuid: ^2.0.0
   webdriver: ^2.0.0
-  webdev: ^2.0.0
-
-dependency_overrides:
-  webdev:
-    path: ../webdev

dwds/test/chrome_proxy_service_test.dart

@@ -15,7 +15,7 @@ import 'package:test/test.dart';
 import 'package:vm_service_lib/vm_service_lib.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
 
-import 'test_context.dart';
+import 'fixtures/context.dart';
 
 final context = TestContext();
 ChromeProxyService get service => context.chromeProxyService;

dwds/test/debug_service_test.dart

@@ -7,7 +7,7 @@ import 'dart:io';
 import 'package:dwds/src/services/debug_service.dart';
 import 'package:test/test.dart';
 
-import 'test_context.dart';
+import 'fixtures/context.dart';
 
 final context = TestContext();
 DebugService get debugService => context.debugService;

dwds/test/debugger_test.dart

@@ -11,9 +11,9 @@ import 'package:dwds/src/debugging/location.dart';
 import 'package:source_maps/parser.dart';
 import 'package:test/test.dart';
 
-import 'debugger_data.dart';
-import 'fakes.dart';
-import 'test_context.dart';
+import 'fixtures/context.dart';
+import 'fixtures/debugger_data.dart';
+import 'fixtures/fakes.dart';
 
 final context = TestContext();
 AppInspector inspector;

dwds/test/test_context.dart renamed to dwds/test/fixtures/context.dart

@@ -1,7 +1,14 @@
+// Copyright (c) 2019, 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 'dart:convert';
 import 'dart:io';
 
+import 'package:build_daemon/client.dart';
+import 'package:build_daemon/data/build_status.dart';
+import 'package:build_daemon/data/build_target.dart';
+import 'package:dwds/dwds.dart';
 import 'package:dwds/src/services/chrome_proxy_service.dart';
 import 'package:dwds/src/services/debug_service.dart';
 import 'package:dwds/src/utilities/shared.dart';
@@ -11,21 +18,25 @@ import 'package:test/test.dart';
 import 'package:webdriver/io.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
 
+import 'server.dart';
+import 'utilities.dart';
+
 class TestContext {
   String appUrl;
   DebugService debugService;
   ChromeProxyService get chromeProxyService =>
       debugService.chromeProxyService as ChromeProxyService;
   WipConnection tabConnection;
-  Process webdev;
+  TestServer testServer;
+  BuildDaemonClient daemonClient;
   WebDriver webDriver;
   Process chromeDriver;
   int port;
 
-  /// The directory in which we run pub serve.
-  String directory;
+  /// Top level directory in which we run the test server..
+  String workingDirectory;
 
-  /// The path to pass to webdev serve.
+  /// The path to build and serve.
   String pathToServe;
 
   /// The path part of the application URL.
@@ -35,7 +46,8 @@ class TestContext {
       {String directory,
       this.path = 'hello_world/index.html',
       this.pathToServe = 'example'}) {
-    this.directory = directory ?? p.relative('../_test', from: p.current);
+    workingDirectory = p.normalize(
+        p.absolute(directory ?? p.relative('../_test', from: p.current)));
   }
 
   Future<void> setUp() async {
@@ -48,26 +60,28 @@ class TestContext {
           'Could not start ChromeDriver. Is it installed?\nError: $e');
     }
 
-    await Process.run('pub', ['get'], workingDirectory: directory);
-
-    webdev = await Process.start(
-        'pub', ['run', 'webdev', 'serve', '$pathToServe:$port'],
-        workingDirectory: directory);
-    webdev.stderr
-        .transform(const Utf8Decoder())
-        .transform(const LineSplitter())
-        .listen(print);
-    var assetReadyCompleter = Completer();
-    webdev.stdout
-        .transform(const Utf8Decoder())
-        .transform(const LineSplitter())
-        .listen((line) {
-      if (line.contains('$port') && !assetReadyCompleter.isCompleted) {
-        assetReadyCompleter.complete();
-      }
-      printOnFailure(line);
-    });
-    await assetReadyCompleter.future.timeout(Duration(seconds: 60));
+    await Process.run('pub', ['get'], workingDirectory: workingDirectory);
+
+    daemonClient = await connectClient(
+        workingDirectory, [], (log) => printOnFailure(log.toString()));
+    testServer = await TestServer.start(
+      'localhost',
+      port,
+      daemonPort(workingDirectory),
+      pathToServe,
+      ReloadConfiguration.none,
+      false,
+      daemonClient.buildResults,
+    );
+    daemonClient.registerBuildTarget(
+        DefaultBuildTarget((b) => b..target = pathToServe));
+    daemonClient.startBuild();
+
+    await daemonClient.buildResults
+        .firstWhere((results) => results.results
+            .any((result) => result.status == BuildStatus.succeeded))
+        .timeout(Duration(seconds: 60));
+
     appUrl = 'http://localhost:$port/$path';
     var debugPort = await findUnusedPort();
     var capabilities = Capabilities.chrome
@@ -108,8 +122,8 @@ class TestContext {
   }
 
   Future<Null> tearDown() async {
-    webdev.kill();
-    await webdev.exitCode;
+    await daemonClient.close();
+    await testServer.stop();
     await webDriver?.quit();
     chromeDriver.kill();
   }

dwds/test/debugger_data.dart renamed to dwds/test/fixtures/debugger_data.dart

@@ -0,0 +1,78 @@
+// Copyright (c) 2019, 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:io';
+
+import 'package:build_daemon/data/build_status.dart';
+import 'package:dwds/dwds.dart';
+import 'package:http_multi_server/http_multi_server.dart';
+import 'package:shelf/shelf.dart';
+import 'package:shelf/shelf_io.dart' as shelf_io;
+
+class TestServer {
+  final HttpServer _server;
+  final String target;
+  final Dwds dwds;
+  final Stream<BuildResult> buildResults;
+
+  TestServer._(
+    this.target,
+    this._server,
+    this.dwds,
+    this.buildResults,
+    bool autoRun,
+  ) {
+    if (autoRun) {
+      dwds.connectedApps.listen((connection) {
+        connection.runMain();
+      });
+    }
+  }
+
+  String get host => _server.address.host;
+  int get port => _server.port;
+
+  Future<void> stop() async {
+    await dwds.stop();
+    await _server.close(force: true);
+  }
+
+  static Future<TestServer> start(
+    String hostname,
+    int port,
+    int assetServerPort,
+    String target,
+    ReloadConfiguration reload,
+    bool startDevTools,
+    Stream<BuildResults> buildResults,
+  ) async {
+    var pipeline = const Pipeline();
+
+    var filteredBuildResults = buildResults.asyncMap<BuildResult>((results) =>
+        results.results.firstWhere((result) => result.target == target));
+
+    var dwds = await Dwds.start(
+      hostname: hostname,
+      applicationPort: port,
+      applicationTarget: target,
+      assetServerPort: assetServerPort,
+      buildResults: filteredBuildResults,
+      chromeConnection: () async => null,
+      logWriter: (level, message) => print(message),
+      reloadConfiguration: reload,
+      serveDevTools: startDevTools,
+      verbose: true,
+    );
+
+    var server = await HttpMultiServer.bind(hostname, port);
+    shelf_io.serveRequests(server, pipeline.addHandler(dwds.handler));
+    return TestServer._(
+      target,
+      server,
+      dwds,
+      filteredBuildResults,
+      true,
+    );
+  }
+}

dwds/test/fakes.dart renamed to dwds/test/fixtures/fakes.dart

@@ -0,0 +1,51 @@
+// Copyright (c) 2019, 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:io';
+
+import 'package:build_daemon/client.dart';
+import 'package:build_daemon/constants.dart';
+import 'package:build_daemon/data/server_log.dart';
+import 'package:path/path.dart' as p;
+
+/// Connects to the `build_runner` daemon.
+Future<BuildDaemonClient> connectClient(String workingDirectory,
+        List<String> options, Function(ServerLog) logHandler) =>
+    BuildDaemonClient.connect(
+        workingDirectory,
+        // On Windows we need to call the snapshot directly otherwise
+        // the process will start in a disjoint cmd without access to
+        // STDIO. We also want to ensure the version of pub is consistent with
+        // the SDK that was used to launch webdev.
+        [dartPath, pubSnapshot]
+          ..addAll(['run', 'build_runner', 'daemon'])
+          ..addAll(options),
+        logHandler: logHandler);
+
+/// The path to the root directory of the SDK.
+final String _sdkDir = (() {
+  // The Dart executable is in "/path/to/sdk/bin/dart", so two levels up is
+  // "/path/to/sdk".
+  var aboveExecutable = p.dirname(p.dirname(Platform.resolvedExecutable));
+  assert(FileSystemEntity.isFileSync(p.join(aboveExecutable, 'version')));
+  return aboveExecutable;
+})();
+
+final String dartPath = p.join(_sdkDir, 'bin', 'dart');
+final String pubSnapshot =
+    p.join(_sdkDir, 'bin', 'snapshots', 'pub.dart.snapshot');
+final String pubPath =
+    p.join(_sdkDir, 'bin', Platform.isWindows ? 'pub.bat' : 'pub');
+
+/// Returns the port of the daemon asset server.
+int daemonPort(String workingDirectory) {
+  var portFile = File(_assetServerPortFilePath(workingDirectory));
+  if (!portFile.existsSync()) {
+    throw Exception('Unable to read daemon asset port file.');
+  }
+  return int.parse(portFile.readAsStringSync());
+}
+
+String _assetServerPortFilePath(String workingDirectory) =>
+    '${daemonWorkspace(workingDirectory)}/.asset_server_port';