Addresses the feedbacks in #95738 (#97457)

chingjun · web-flow · commit a504b9377495 · 2022-02-02T13:55:22.000-08:00
diff --git a/packages/flutter_tools/lib/src/commands/daemon.dart b/packages/flutter_tools/lib/src/commands/daemon.dart
@@ -1340,12 +1340,38 @@ class ProxyDomain extends Domain {
   Future<String> connect(Map<String, dynamic> args) async {
     final int targetPort = _getIntArg(args, 'port', required: true);
     final String id = 'portForwarder_${targetPort}_${_id++}';
-    final Socket socket = await Socket.connect('127.0.0.1', targetPort);
+
+    Socket socket;
+
+    try {
+      socket = await Socket.connect(InternetAddress.loopbackIPv4, targetPort);
+    } on SocketException {
+      globals.logger.printTrace('Connecting to localhost:$targetPort failed with IPv4');
+    }
+
+    try {
+      // If connecting to IPv4 loopback interface fails, try IPv6.
+      socket ??= await Socket.connect(InternetAddress.loopbackIPv6, targetPort);
+    } on SocketException {
+      globals.logger.printError('Connecting to localhost:$targetPort failed');
+    }
+
+    if (socket == null) {
+      throw Exception('Failed to connect to the port');
+    }
+
     _forwardedConnections[id] = socket;
     socket.listen((List<int> data) {
       sendEvent('proxy.data.$id', null, data);
+    }, onError: (dynamic error, StackTrace stackTrace) {
+      // Socket error, probably disconnected.
+      globals.logger.printTrace('Socket error: $error, $stackTrace');
     });
-    unawaited(socket.done.then((dynamic _) {
+
+    unawaited(socket.done.catchError((dynamic error, StackTrace stackTrace) {
+      // Socket error, probably disconnected.
+      globals.logger.printTrace('Socket error: $error, $stackTrace');
+    }).then((dynamic _) {
       sendEvent('proxy.disconnected.$id');
     }));
     return id;
@@ -1376,7 +1402,7 @@ class ProxyDomain extends Domain {
   @override
   Future<void> dispose() async {
     for (final Socket connection in _forwardedConnections.values) {
-      await connection.close();
+      connection.destroy();
     }
     await _tempDirectory?.delete(recursive: true);
   }
diff --git a/packages/flutter_tools/lib/src/daemon.dart b/packages/flutter_tools/lib/src/daemon.dart
@@ -98,39 +98,11 @@ class DaemonInputStreamConverter {
 
   // Processes a single chunk received in the input stream.
   void _processChunk(List<int> chunk) {
-    const int LF = 10; // The '\n' character
 
     int start = 0;
     while (start < chunk.length) {
       if (state == _InputStreamParseState.json) {
-        // Search for newline character.
-        final int indexOfNewLine = chunk.indexOf(LF, start);
-        if (indexOfNewLine < 0) {
-          bytesBuilder.add(chunk.sublist(start));
-          start = chunk.length;
-        } else {
-          bytesBuilder.add(chunk.sublist(start, indexOfNewLine + 1));
-          start = indexOfNewLine + 1;
-
-          // Process chunk here
-          final Uint8List combinedChunk = bytesBuilder.takeBytes();
-          String jsonString = utf8.decode(combinedChunk).trim();
-          if (jsonString.startsWith('[{') && jsonString.endsWith('}]')) {
-            jsonString = jsonString.substring(1, jsonString.length - 1);
-            final Map<String, Object?>? value = castStringKeyedMap(json.decode(jsonString));
-            if (value != null) {
-              // Check if we need to consume another binary blob.
-              if (value[_binaryLengthKey] != null) {
-                remainingBinaryLength = value[_binaryLengthKey]! as int;
-                currentBinaryStream = StreamController<List<int>>();
-                state = _InputStreamParseState.binary;
-                _controller.add(DaemonMessage(value, currentBinaryStream.stream));
-              } else {
-                _controller.add(DaemonMessage(value));
-              }
-            }
-          }
-        }
+        start += _processChunkInJsonMode(chunk, start);
       } else if (state == _InputStreamParseState.binary) {
         final int bytesSent = _addBinaryChunk(chunk, start, remainingBinaryLength);
         start += bytesSent;
@@ -146,6 +118,41 @@ class DaemonInputStreamConverter {
     }
   }
 
+  /// Processes a chunk in JSON mode, and returns the number of bytes processed.
+  int _processChunkInJsonMode(List<int> chunk, int start) {
+    const int LF = 10; // The '\n' character
+
+    // Search for newline character.
+    final int indexOfNewLine = chunk.indexOf(LF, start);
+    if (indexOfNewLine < 0) {
+      bytesBuilder.add(chunk.sublist(start));
+      return chunk.length - start;
+    }
+
+    bytesBuilder.add(chunk.sublist(start, indexOfNewLine + 1));
+
+    // Process chunk here
+    final Uint8List combinedChunk = bytesBuilder.takeBytes();
+    String jsonString = utf8.decode(combinedChunk).trim();
+    if (jsonString.startsWith('[{') && jsonString.endsWith('}]')) {
+      jsonString = jsonString.substring(1, jsonString.length - 1);
+      final Map<String, Object?>? value = castStringKeyedMap(json.decode(jsonString));
+      if (value != null) {
+        // Check if we need to consume another binary blob.
+        if (value[_binaryLengthKey] != null) {
+          remainingBinaryLength = value[_binaryLengthKey]! as int;
+          currentBinaryStream = StreamController<List<int>>();
+          state = _InputStreamParseState.binary;
+          _controller.add(DaemonMessage(value, currentBinaryStream.stream));
+        } else {
+          _controller.add(DaemonMessage(value));
+        }
+      }
+    }
+
+    return indexOfNewLine + 1 - start;
+  }
+
   int _addBinaryChunk(List<int> chunk, int start, int maximumSizeToRead) {
     if (start == 0 && chunk.length <= remainingBinaryLength) {
       currentBinaryStream.add(chunk);
@@ -170,6 +177,32 @@ class DaemonStreams {
     inputStream = DaemonInputStreamConverter(rawInputStream).convertedStream,
     _logger = logger;
 
+  /// Creates a [DaemonStreams] that uses stdin and stdout as the underlying streams.
+  DaemonStreams.fromStdio(Stdio stdio, { required Logger logger })
+    : this(stdio.stdin, stdio.stdout, logger: logger);
+
+  /// Creates a [DaemonStreams] that uses [Socket] as the underlying streams.
+  DaemonStreams.fromSocket(Socket socket, { required Logger logger })
+    : this(socket, socket, logger: logger);
+
+  /// Connects to a server and creates a [DaemonStreams] from the connection as the underlying streams.
+  factory DaemonStreams.connect(String host, int port, { required Logger logger }) {
+    final Future<Socket> socketFuture = Socket.connect(host, port);
+    final StreamController<List<int>> inputStreamController = StreamController<List<int>>();
+    final StreamController<List<int>> outputStreamController = StreamController<List<int>>();
+    socketFuture.then((Socket socket) {
+      inputStreamController.addStream(socket);
+      socket.addStream(outputStreamController.stream);
+    }).onError((Object error, StackTrace stackTrace) {
+      logger.printError('Socket error: $error');
+      logger.printTrace('$stackTrace');
+      // Propagate the error to the streams.
+      inputStreamController.addError(error, stackTrace);
+      unawaited(outputStreamController.close());
+    });
+    return DaemonStreams(inputStreamController.stream, outputStreamController.sink, logger: logger);
+  }
+
   final StreamSink<List<int>> _outputSink;
   final Logger _logger;
 
@@ -197,28 +230,6 @@ class DaemonStreams {
   Future<void> dispose() async {
     unawaited(_outputSink.close());
   }
-
-  /// Creates a [DaemonStreams] that uses stdin and stdout as the underlying streams.
-  static DaemonStreams fromStdio(Stdio stdio, { required Logger logger }) {
-    return DaemonStreams(stdio.stdin, stdio.stdout, logger: logger);
-  }
-
-  /// Creates a [DaemonStreams] that uses [Socket] as the underlying streams.
-  static DaemonStreams fromSocket(Socket socket, { required Logger logger }) {
-    return DaemonStreams(socket, socket, logger: logger);
-  }
-
-  /// Connects to a server and creates a [DaemonStreams] from the connection as the underlying streams.
-  static DaemonStreams connect(String host, int port, { required Logger logger }) {
-    final Future<Socket> socketFuture = Socket.connect(host, port);
-    final StreamController<List<int>> inputStreamController = StreamController<List<int>>();
-    final StreamController<List<int>> outputStreamController = StreamController<List<int>>();
-    socketFuture.then((Socket socket) {
-      inputStreamController.addStream(socket);
-      socket.addStream(outputStreamController.stream);
-    });
-    return DaemonStreams(inputStreamController.stream, outputStreamController.sink, logger: logger);
-  }
 }
 
 /// Connection between a flutter daemon and a client.
diff --git a/packages/flutter_tools/lib/src/device.dart b/packages/flutter_tools/lib/src/device.dart
@@ -39,15 +39,11 @@ class Category {
   String toString() => value;
 
   static Category? fromString(String category) {
-    switch (category) {
-      case 'web':
-        return web;
-      case 'desktop':
-        return desktop;
-      case 'mobile':
-        return mobile;
-    }
-    return null;
+    return <String, Category>{
+      'web': web,
+      'desktop': desktop,
+      'mobile': mobile,
+    }[category];
   }
 }
 
@@ -70,25 +66,16 @@ class PlatformType {
   String toString() => value;
 
   static PlatformType? fromString(String platformType) {
-    switch (platformType) {
-      case 'web':
-        return web;
-      case 'android':
-        return android;
-      case 'ios':
-        return ios;
-      case 'linux':
-        return linux;
-      case 'macos':
-        return macos;
-      case 'windows':
-        return windows;
-      case 'fuchsia':
-        return fuchsia;
-      case 'custom':
-        return custom;
-    }
-    return null;
+    return <String, PlatformType>{
+      'web': web,
+      'android': android,
+      'ios': ios,
+      'linux': linux,
+      'macos': macos,
+      'windows': windows,
+      'fuchsia': fuchsia,
+      'custom': custom,
+    }[platformType];
   }
 }
 
diff --git a/packages/flutter_tools/test/commands.shard/hermetic/daemon_test.dart b/packages/flutter_tools/test/commands.shard/hermetic/daemon_test.dart
