| // Copyright (c) 2018, 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:html'; |
| import 'dart:typed_data'; |
| |
| import 'package:pedantic/pedantic.dart' show unawaited; |
| |
| import 'base_client.dart'; |
| import 'base_request.dart'; |
| import 'byte_stream.dart'; |
| import 'exception.dart'; |
| import 'streamed_response.dart'; |
| |
| /// Used from conditional imports, matches the definition in `client_stub.dart`. |
| BaseClient createClient() => BrowserClient(); |
| |
| /// A `dart:html`-based HTTP client that runs in the browser and is backed by |
| /// XMLHttpRequests. |
| /// |
| /// This client inherits some of the limitations of XMLHttpRequest. It ignores |
| /// the [BaseRequest.contentLength], [BaseRequest.persistentConnection], |
| /// [BaseRequest.followRedirects], and [BaseRequest.maxRedirects] fields. It is |
| /// also unable to stream requests or responses; a request will only be sent and |
| /// a response will only be returned once all the data is available. |
| class BrowserClient extends BaseClient { |
| /// The currently active XHRs. |
| /// |
| /// These are aborted if the client is closed. |
| final _xhrs = Set<HttpRequest>(); |
| |
| /// Creates a new HTTP client. |
| BrowserClient(); |
| |
| /// Whether to send credentials such as cookies or authorization headers for |
| /// cross-site requests. |
| /// |
| /// Defaults to `false`. |
| bool withCredentials = false; |
| |
| /// Sends an HTTP request and asynchronously returns the response. |
| Future<StreamedResponse> send(BaseRequest request) async { |
| var bytes = await request.finalize().toBytes(); |
| var xhr = HttpRequest(); |
| _xhrs.add(xhr); |
| _openHttpRequest(xhr, request.method, request.url.toString(), asynch: true); |
| xhr.responseType = 'blob'; |
| xhr.withCredentials = withCredentials; |
| request.headers.forEach(xhr.setRequestHeader); |
| |
| var completer = Completer<StreamedResponse>(); |
| unawaited(xhr.onLoad.first.then((_) { |
| // TODO(nweiz): Set the response type to "arraybuffer" when issue 18542 |
| // is fixed. |
| var blob = xhr.response == null ? Blob([]) : xhr.response; |
| var reader = FileReader(); |
| |
| reader.onLoad.first.then((_) { |
| var body = reader.result as Uint8List; |
| completer.complete(StreamedResponse( |
| ByteStream.fromBytes(body), xhr.status, |
| contentLength: body.length, |
| request: request, |
| headers: xhr.responseHeaders, |
| reasonPhrase: xhr.statusText)); |
| }); |
| |
| reader.onError.first.then((error) { |
| completer.completeError( |
| ClientException(error.toString(), request.url), StackTrace.current); |
| }); |
| |
| reader.readAsArrayBuffer(blob); |
| })); |
| |
| unawaited(xhr.onError.first.then((_) { |
| // Unfortunately, the underlying XMLHttpRequest API doesn't expose any |
| // specific information about the error itself. |
| completer.completeError( |
| ClientException("XMLHttpRequest error.", request.url), |
| StackTrace.current); |
| })); |
| |
| xhr.send(bytes); |
| |
| try { |
| return await completer.future; |
| } finally { |
| _xhrs.remove(xhr); |
| } |
| } |
| |
| // TODO(nweiz): Remove this when sdk#24637 is fixed. |
| void _openHttpRequest(HttpRequest request, String method, String url, |
| {bool asynch, String user, String password}) { |
| request.open(method, url, async: asynch, user: user, password: password); |
| } |
| |
| /// Closes the client. |
| /// |
| /// This terminates all active requests. |
| void close() { |
| for (var xhr in _xhrs) { |
| xhr.abort(); |
| } |
| } |
| } |