Add an HTTP library that wraps dart:io.

pkg/http/lib/src/request.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 request;
+
+import 'dart:io';
+import 'dart:scalarlist';
+import 'dart:uri';
+
+import 'base_request.dart';
+import 'utils.dart';
+
+/// An HTTP request where the entire request body is known in advance.
+class Request extends BaseRequest {
+  /// The size of the request body, in bytes. This is calculated from
+  /// [bodyBytes].
+  ///
+  /// The content length cannot be set for [Request], since it's automatically
+  /// calculated from [bodyBytes].
+  int get contentLength => bodyBytes.length;
+
+  set contentLength(int value) {
+    throw new UnsupportedError("Cannot set the contentLength property of "
+        "non-streaming Request objects.");
+  }
+
+  /// The default encoding to use when converting between [bodyBytes] and
+  /// [body]. This is only used if [encoding] hasn't been manually set and if
+  /// the content-type header has no encoding information.
+  Encoding _defaultEncoding;
+
+  /// The encoding used for the request. This encoding is used when converting
+  /// between [bodyBytes] and [body].
+  ///
+  /// If the request has a `Content-Type` header and that header has a `charset`
+  /// parameter, that parameter's value is used as the encoding. Otherwise, if
+  /// [encoding] has been set manually, that encoding is used. If that hasn't
+  /// been set either, this defaults to [Encoding.UTF_8].
+  ///
+  /// If the `charset` parameter's value is not a known [Encoding], reading this
+  /// will throw a [FormatException].
+  ///
+  /// If the request has a `Content-Type` header, setting this will set the
+  /// charset parameter on that header.
+  Encoding get encoding {
+    if (_contentType == null || _contentType.charset == null) {
+      return _defaultEncoding;
+    }
+    return requiredEncodingForCharset(_contentType.charset);
+  }
+
+  set encoding(Encoding value) {
+    _checkFinalized();
+    _defaultEncoding = value;
+    var contentType = _contentType;
+    if (contentType != null) {
+      contentType.charset = value.name;
+      _contentType = contentType;
+    }
+  }
+
+  // TODO(nweiz): make this return a read-only view
+  /// The bytes comprising the body of the request. This is converted to and
+  /// from [body] using [encoding].
+  ///
+  /// This list should only be set, not be modified in place.
+  Uint8List get bodyBytes => _bodyBytes;
+  Uint8List _bodyBytes;
+
+  set bodyBytes(List<int> value) {
+    _checkFinalized();
+    _bodyBytes = toUint8List(value);
+  }
+
+  /// The body of the request as a string. This is converted to and from
+  /// [bodyBytes] using [encoding].
+  ///
+  /// When this is set, if the request does not yet have a `Content-Type`
+  /// header, one will be added with the type `text/plain`. Then the `charset`
+  /// parameter of the `Content-Type` header (whether new or pre-existing) will
+  /// be set to [encoding] if it wasn't already set.
+  String get body => decodeString(bodyBytes, encoding);
+
+  set body(String value) {
+    bodyBytes = encodeString(value, encoding);
+    var contentType = _contentType;
+    if (contentType == null) contentType = new ContentType("text", "plain");
+    if (contentType.charset == null) contentType.charset = encoding.name;
+    _contentType = contentType;
+  }
+
+  /// The form-encoded fields in the body of the request as a map from field
+  /// names to values. The form-encoded body is converted to and from
+  /// [bodyBytes] using [encoding] (in the same way as [body]).
+  ///
+  /// If the request doesn't have a `Content-Type` header of
+  /// `application/x-www-form-urlencoded`, reading this will throw a
+  /// [StateError].
+  ///
+  /// If the request has a `Content-Type` header with a type other than
+  /// `application/x-www-form-urlencoded`, setting this will throw a
+  /// [StateError]. Otherwise, the content type will be set to
+  /// `application/x-www-form-urlencoded`.
+  ///
+  /// This map should only be set, not modified in place.
+  Map<String, String> get bodyFields {
+    if (_contentType == null ||
+        _contentType.value != "application/x-www-form-urlencoded") {
+      throw new StateError('Cannot access the body fields of a Request without '
+          'content-type "application/x-www-form-urlencoded".');
+    }
+
+    return queryToMap(body);
+  }
+
+  set bodyFields(Map<String, String> fields) {
+    if (_contentType == null) {
+      _contentType = new ContentType("application", "x-www-form-urlencoded");
+    } else if (_contentType.value != "application/x-www-form-urlencoded") {
+      throw new StateError('Cannot set the body fields of a Request with '
+          'content-type "${_contentType.value}".');
+    }
+
+    this.body = mapToQuery(fields);
+  }
+
+  /// Creates a new HTTP request.
+  Request(String method, Uri url)
+    : super(method, url),
+      _defaultEncoding = Encoding.UTF_8,
+      _bodyBytes = new Uint8List(0);
+
+  /// Freeze all mutable fields and return an [InputStream] containing the
+  /// request body.
+  InputStream finalize() {
+    super.finalize();
+
+    var stream = new ListInputStream();
+    stream.write(bodyBytes);
+    stream.markEndOfStream();
+    return stream;
+  }
+
+  /// The `Content-Type` header of the request (if it exists) as a
+  /// [ContentType].
+  ContentType get _contentType {
+    var contentType = headers[HttpHeaders.CONTENT_TYPE];
+    if (contentType == null) return null;
+    return new ContentType.fromString(contentType);
+  }
+
+  set _contentType(ContentType value) {
+    headers[HttpHeaders.CONTENT_TYPE] = value.toString();
+  }
+
+  /// Throw an error if this request has been finalized.
+  void _checkFinalized() {
+    if (!finalized) return;
+    throw new StateError("Can't modify a finalized Request.");
+  }
+}