Header support

lib/core/ros.dart

@@ -23,13 +23,16 @@ enum TopicStatus { SUBSCRIBED, UNSUBSCRIBED, PUBLISHER, ADVERTISED, UNADVERTISED
 class Ros {
   /// Initializes the [_statusController] as a broadcast.
   /// The [url] of the ROS node can be optionally specified at this point.
-  Ros({this.url}) {
+  Ros({this.url, this.headers}) {
     _statusController = StreamController<Status>.broadcast();
   }
 
   /// The url of ROS node running the rosbridge server.
   dynamic url;
 
+  /// The socket connection header.
+  Map<String, dynamic> headers;
+
   /// Total subscribers to ever connect.
   int subscribers = 0;
 
@@ -64,12 +67,15 @@ class Ros {
   Status status = Status.NONE;
 
   /// Connect to the ROS node, the [url] can override what was provided in the constructor.
-  void connect({dynamic url}) {
+  void connect({dynamic url, Map<String, dynamic> headers}) {
     this.url = url ?? this.url;
     url ??= this.url;
+    this.headers = headers ?? this.headers;
+    headers ??= this.headers;
+
     try {
       // Initialize the connection to the ROS node with a Websocket channel.
-      _channel = initializeWebSocketChannel(url);
+      _channel = initializeWebSocketChannel(url, headers);
       stream = _channel.stream.asBroadcastStream().map((raw) => json.decode(raw));
       // Update the connection status.
       status = Status.CONNECTED;

lib/core/ros_html.dart

@@ -1,6 +1,6 @@
 import 'package:web_socket_channel/web_socket_channel.dart';
 import 'package:web_socket_channel/html.dart';
 
-WebSocketChannel initializeWebSocketChannel(String url) {
+WebSocketChannel initializeWebSocketChannel(String url, Map<String, dynamic> headers) {
   return HtmlWebSocketChannel.connect(url);
 }

lib/core/ros_io.dart

@@ -1,6 +1,6 @@
 import 'package:web_socket_channel/web_socket_channel.dart';
 import 'package:web_socket_channel/io.dart';
 
-WebSocketChannel initializeWebSocketChannel(String url) {
-  return IOWebSocketChannel.connect(url);
+WebSocketChannel initializeWebSocketChannel(String url, Map<String,dynamic> headers) {
+  return IOWebSocketChannel.connect(url, headers: headers);
 }

lib/core/ros_stub.dart

@@ -1,6 +1,6 @@
 import 'package:web_socket_channel/web_socket_channel.dart';
 
 //Implemented in `ros_html.dart` and `ros_io.dart`
-WebSocketChannel initializeWebSocketChannel(String url) {
+WebSocketChannel initializeWebSocketChannel(String url, Map<String, dynamic> headers) {
   throw UnsupportedError('Cannot create a web socket channel without dart:html or dart:io.');
 }

pubspec.lock

@@ -1,5 +1,5 @@
 # Generated by pub
-# See https://www.dartlang.org/tools/pub/glossary#lockfile
+# See https://dart.dev/tools/pub/glossary#lockfile
 packages:
   analyzer:
     dependency: transitive