Add an HTTP library that wraps dart:io.

pkg/http/lib/src/client.dart

+// Copyright (c) 2012, 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.
+
+library client;
+
+import 'dart:io';
+
+import 'base_client.dart';
+import 'base_request.dart';
+import 'streamed_response.dart';
+import 'utils.dart';
+
+/// An HTTP client which takes care of maintaining persistent connections across
+/// multiple requests to the same server. If you only need to send a single
+/// request, it's usually easier to use [head], [get], [post],
+/// [put], or [delete] instead.
+///
+/// When creating an HTTP client class with additional functionality, it's
+/// recommended that you subclass [BaseClient] and wrap another instance of
+/// [BaseClient] rather than subclassing [Client] directly. This allows all
+/// subclasses of [BaseClient] to be mutually composable.
+class Client extends BaseClient {
+  /// The underlying `dart:io` HTTP client.
+  HttpClient _inner;
+
+  /// Creates a new HTTP client.
+  Client() : _inner = new HttpClient();
+
+  /// Sends an HTTP request and asynchronously returns the response.
+  Future<StreamedResponse> send(BaseRequest request) {
+    var stream = request.finalize();
+
+    var completer = new Completer<StreamedResponse>();
+    var connection = _inner.openUrl(request.method, request.url);
+    connection.onError = (e) {
+      async.then((_) {
+        // TODO(nweiz): remove this when issue 4974 is fixed
+        if (completer.future.isComplete) throw e;
+
+        completer.completeException(e);
+      });
+    };
+
+    connection.onRequest = (underlyingRequest) {
+      underlyingRequest.contentLength = request.contentLength;
+      underlyingRequest.persistentConnection = request.persistentConnection;
+      request.headers.forEach((name, value) {
+        underlyingRequest.headers.set(name, value);
+      });
+
+      if (stream.closed) {
+        underlyingRequest.outputStream.close();
+      } else {
+        stream.pipe(underlyingRequest.outputStream);
+      }
+    };
+
+    connection.onResponse = (response) {
+      var headers = <String>{};
+      response.headers.forEach((key, value) => headers[key] = value);
+
+      completer.complete(new StreamedResponse(
+          response.inputStream,
+          response.statusCode,
+          response.contentLength,
+          headers: headers,
+          isRedirect: response.isRedirect,
+          persistentConnection: response.persistentConnection,
+          reasonPhrase: response.reasonPhrase));
+    };
+
+    return completer.future;
+  }
+
+  /// Closes the client. This terminates all active connections. If a client
+  /// remains unclosed, the Dart process may not terminate.
+  void close() {
+    if (_inner != null) _inner.shutdown();
+    _inner = null;
+  }
+}