update: Migrate off legacy JS/HTML apis

lib/grpc_or_grpcweb.dart

@@ -13,8 +13,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import 'src/client/grpc_or_grpcweb_channel_grpc.dart'
-    if (dart.library.html) 'src/client/grpc_or_grpcweb_channel_web.dart';
+import 'src/client/grpc_or_grpcweb_channel_web.dart'
+    if (dart.library.io) 'src/client/grpc_or_grpcweb_channel_grpc.dart';
 import 'src/client/http2_channel.dart';
 import 'src/client/options.dart';
 

lib/src/client/transport/xhr_transport.dart

@@ -14,10 +14,11 @@
 // limitations under the License.
 
 import 'dart:async';
-import 'dart:html';
+import 'dart:js_interop';
 import 'dart:typed_data';
 
 import 'package:meta/meta.dart';
+import 'package:web/web.dart';
 
 import '../../client/call.dart';
 import '../../shared/message.dart';
@@ -30,7 +31,7 @@ import 'web_streams.dart';
 const _contentTypeKey = 'Content-Type';
 
 class XhrTransportStream implements GrpcTransportStream {
-  final HttpRequest _request;
+  final XMLHttpRequest _request;
   final ErrorHandler _onError;
   final Function(XhrTransportStream stream) _onDone;
   bool _headersReceived = false;
@@ -45,23 +46,22 @@ class XhrTransportStream implements GrpcTransportStream {
   @override
   StreamSink<List<int>> get outgoingMessages => _outgoingMessages.sink;
 
-  XhrTransportStream(this._request,
-      {required ErrorHandler onError, required onDone})
+  XhrTransportStream(this._request, {required ErrorHandler onError, required onDone})
       : _onError = onError,
         _onDone = onDone {
     _outgoingMessages.stream
         .map(frame)
-        .listen((data) => _request.send(data), cancelOnError: true);
+        .listen((data) => _request.send(Int8List.fromList(data).toJS), cancelOnError: true, onError: _onError);
 
-    _request.onReadyStateChange.listen((data) {
+    _request.onReadyStateChange.listen((_) {
       if (_incomingProcessor.isClosed) {
         return;
       }
       switch (_request.readyState) {
-        case HttpRequest.HEADERS_RECEIVED:
+        case 2:
           _onHeadersReceived();
           break;
-        case HttpRequest.DONE:
+        case 4:
           _onRequestDone();
           _close();
           break;
@@ -72,8 +72,7 @@ class XhrTransportStream implements GrpcTransportStream {
       if (_incomingProcessor.isClosed) {
         return;
       }
-      _onError(GrpcError.unavailable('XhrConnection connection-error'),
-          StackTrace.current);
+      _onError(GrpcError.unavailable('XhrConnection connection-error'), StackTrace.current);
       terminate();
     });
 
@@ -81,27 +80,21 @@ class XhrTransportStream implements GrpcTransportStream {
       if (_incomingProcessor.isClosed) {
         return;
       }
-      // Use response over responseText as most browsers don't support
-      // using responseText during an onProgress event.
-      final responseString = _request.response as String;
-      final bytes = Uint8List.fromList(
-              responseString.substring(_requestBytesRead).codeUnits)
-          .buffer;
-      _requestBytesRead = responseString.length;
+      final responseText = _request.responseText;
+      final bytes = Uint8List.fromList(responseText.substring(_requestBytesRead).codeUnits).buffer;
+      _requestBytesRead = responseText.length;
       _incomingProcessor.add(bytes);
     });
 
     _incomingProcessor.stream
         .transform(GrpcWebDecoder())
         .transform(grpcDecompressor())
-        .listen(_incomingMessages.add,
-            onError: _onError, onDone: _incomingMessages.close);
+        .listen(_incomingMessages.add, onError: _onError, onDone: _incomingMessages.close);
   }
 
   bool _validateResponseState() {
     try {
-      validateHttpStatusAndContentType(
-          _request.status, _request.responseHeaders,
+      validateHttpStatusAndContentType(_request.status, _parseHeaders(_request.getAllResponseHeaders()),
           rawResponse: _request.responseText);
       return true;
     } catch (e, st) {
@@ -115,17 +108,15 @@ class XhrTransportStream implements GrpcTransportStream {
     if (!_validateResponseState()) {
       return;
     }
-    _incomingMessages.add(GrpcMetadata(_request.responseHeaders));
+    _incomingMessages.add(GrpcMetadata(_parseHeaders(_request.getAllResponseHeaders())));
   }
 
   void _onRequestDone() {
     if (!_headersReceived && !_validateResponseState()) {
       return;
     }
-    if (_request.response == null) {
-      _onError(
-          GrpcError.unavailable('XhrConnection request null response', null,
-              _request.responseText),
+    if (_request.status != 200) {
+      _onError(GrpcError.unavailable('Request failed with status: ${_request.status}', null, _request.responseText),
           StackTrace.current);
       return;
     }
@@ -137,6 +128,20 @@ class XhrTransportStream implements GrpcTransportStream {
     _onDone(this);
   }
 
+  Map<String, String> _parseHeaders(String rawHeaders) {
+    final headers = <String, String>{};
+    final lines = rawHeaders.split('\r\n');
+    for (var line in lines) {
+      final index = line.indexOf(': ');
+      if (index != -1) {
+        final key = line.substring(0, index);
+        final value = line.substring(index + 2);
+        headers[key] = value;
+      }
+    }
+    return headers;
+  }
+
   @override
   Future<void> terminate() async {
     _close();
@@ -153,24 +158,24 @@ class XhrClientConnection implements ClientConnection {
 
   @override
   String get authority => uri.authority;
+
   @override
   String get scheme => uri.scheme;
 
-  void _initializeRequest(HttpRequest request, Map<String, String> metadata) {
-    for (final header in metadata.keys) {
-      request.setRequestHeader(header, metadata[header]!);
-    }
+  void _initializeRequest(XMLHttpRequest request, Map<String, String> metadata) {
+    metadata.forEach((key, value) {
+      request.setRequestHeader(key, value);
+    });
     // Overriding the mimetype allows us to stream and parse the data
     request.overrideMimeType('text/plain; charset=x-user-defined');
     request.responseType = 'text';
   }
 
   @visibleForTesting
-  HttpRequest createHttpRequest() => HttpRequest();
+  XMLHttpRequest createHttpRequest() => XMLHttpRequest();
 
   @override
-  GrpcTransportStream makeRequest(String path, Duration? timeout,
-      Map<String, String> metadata, ErrorHandler onError,
+  GrpcTransportStream makeRequest(String path, Duration? timeout, Map<String, String> metadata, ErrorHandler onError,
       {CallOptions? callOptions}) {
     // gRPC-web headers.
     if (_getContentTypeHeader(metadata) == null) {
@@ -180,8 +185,7 @@ class XhrClientConnection implements ClientConnection {
     }
 
     var requestUri = uri.resolve(path);
-    if (callOptions is WebCallOptions &&
-        callOptions.bypassCorsPreflight == true) {
+    if (callOptions is WebCallOptions && callOptions.bypassCorsPreflight == true) {
       requestUri = cors.moveHttpHeadersToQueryParam(metadata, requestUri);
     }
 
@@ -193,8 +197,7 @@ class XhrClientConnection implements ClientConnection {
     // Must set headers after calling open().
     _initializeRequest(request, metadata);
 
-    final transportStream =
-        XhrTransportStream(request, onError: onError, onDone: _removeStream);
+    final transportStream = XhrTransportStream(request, onError: onError, onDone: _removeStream);
     _requests.add(transportStream);
     return transportStream;
   }

pubspec.yaml

@@ -17,6 +17,7 @@ dependencies:
   http2: ^2.2.0
   protobuf: '>=2.0.0 <4.0.0'
   clock: ^1.1.1
+  web: ^1.0.0
 
 dev_dependencies:
   build_runner: ^2.0.0