Request now has the same body model as Response

lib/src/response.dart

 // Copyright (c) 2014, 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 shelf.response;
 
-import 'dart:async';
 import 'dart:convert';
 
 import 'package:http_parser/http_parser.dart';
 
 import 'message.dart';
 import 'util.dart';
 
 /// The response returned by a [Handler].
 class Response extends Message {
   /// The HTTP status code of the response.
@@ skipping 99 matching lines @@
       : this._redirect(303, location, body, headers, encoding,
           context: context);
 
   /// Constructs a helper constructor for redirect responses.
   Response._redirect(int statusCode, location, body,
       Map<String, String> headers, Encoding encoding,
       { Map<String, Object> context })
       : this(statusCode,
             body: body,
             encoding: encoding,
-            headers: _addHeader(
+            headers: addHeader(
                 headers, 'location', _locationToString(location)),
             context: context);
 
   /// Constructs a 304 Not Modified response.
   ///
   /// This is used to respond to a conditional GET request that provided
   /// information used to determine whether the requested resource has changed
   /// since the last request. It indicates that the resource has not changed and
   /// the old value should be used.
   Response.notModified({Map<String, String> headers,
     Map<String, Object> context})
-      : this(304, headers: _addHeader(
+      : this(304, headers: addHeader(
             headers, 'date', formatHttpDate(new DateTime.now())),
             context: context);
 
   /// Constructs a 403 Forbidden response.
   ///
   /// This indicates that the server is refusing to fulfill the request.
   ///
   /// [body] is the response body. It may be a [String], a [Stream<List<int>>],
   /// or `null`. If it's a [String], [encoding] is used to encode it to a
   /// [Stream<List<int>>]. The default encoding is UTF-8. If it's `null` or not
@@ skipping 56 matching lines @@
   /// [body] is the response body. It may be either a [String], a
   /// [Stream<List<int>>], or `null` to indicate no body.
   /// If it's a [String], [encoding] is used to encode it to a
   /// [Stream<List<int>>]. The default encoding is UTF-8.
   ///
   /// If [encoding] is passed, the "encoding" field of the Content-Type header
   /// in [headers] will be set appropriately. If there is no existing
   /// Content-Type header, it will be set to "application/octet-stream".
   Response(this.statusCode, {body, Map<String, String> headers,
       Encoding encoding, Map<String, Object> context})
-      : super(_bodyToStream(body, encoding),
-          headers: _adjustHeaders(headers, encoding),
-          context: context) {
+      : super(body, encoding: encoding, headers: headers, context: context) {
     if (statusCode < 100) {
       throw new ArgumentError("Invalid status code: $statusCode.");
     }
   }
 
   /// Creates a new [Response] by copying existing values and applying specified
   /// changes.
   ///
   /// New key-value pairs in [context] and [headers] will be added to the copied
   /// [Response].
   ///
   /// If [context] or [headers] includes a key that already exists, the
   /// key-value pair will replace the corresponding entry in the copied
   /// [Response].
   ///
   /// All other context and header values from the [Response] will be included
   /// in the copied [Response] unchanged.
   Response change({Map<String, String> headers, Map<String, Object> context}) {
     headers = updateMap(this.headers, headers);
     context = updateMap(this.context, context);
 
     return new Response(this.statusCode, body: this.read(), headers: headers,
         context: context);
   }
 }
 
-/// Converts [body] to a byte stream.
-///
-/// [body] may be either a [String], a [Stream<List<int>>], or `null`. If it's a
-/// [String], [encoding] will be used to convert it to a [Stream<List<int>>].
-Stream<List<int>> _bodyToStream(body, Encoding encoding) {
-  if (encoding == null) encoding = UTF8;
-  if (body == null) return new Stream.fromIterable([]);
-  if (body is String) return new Stream.fromIterable([encoding.encode(body)]);
-  if (body is Stream) return body;
-
-  throw new ArgumentError('Response body "$body" must be a String or a '
-      'Stream.');
-}
-
-/// Adds information about [encoding] to [headers].
-///
-/// Returns a new map without modifying [headers].
-Map<String, String> _adjustHeaders(
-    Map<String, String> headers, Encoding encoding) {
-  if (headers == null) headers = const {};
-  if (encoding == null) return headers;
-  if (headers['content-type'] == null) {
-    return _addHeader(headers, 'content-type',
-        'application/octet-stream; charset=${encoding.name}');
-  }
-
-  var contentType = new MediaType.parse(headers['content-type'])
-      .change(parameters: {'charset': encoding.name});
-  return _addHeader(headers, 'content-type', contentType.toString());
-}
-
-/// Adds a header with [name] and [value] to [headers], which may be null.
-///
-/// Returns a new map without modifying [headers].
-Map<String, String> _addHeader(
-    Map<String, String> headers, String name, String value) {
-  headers = headers == null ? {} : new Map.from(headers);
-  headers[name] = value;
-  return headers;
-}
-
 /// Adds content-type information to [headers].
 ///
 /// Returns a new map without modifying [headers]. This is used to add
 /// content-type information when creating a 500 response with a default body.
 Map<String, String> _adjustErrorHeaders(Map<String, String> headers) {
   if (headers == null || headers['content-type'] == null) {
-    return _addHeader(headers, 'content-type', 'text/plain');
+    return addHeader(headers, 'content-type', 'text/plain');
   }
 
   var contentType = new MediaType.parse(headers['content-type'])
       .change(mimeType: 'text/plain');
-  return _addHeader(headers, 'content-type', contentType.toString());
+  return addHeader(headers, 'content-type', contentType.toString());
 }
 
 /// Converts [location], which may be a [String] or a [Uri], to a [String].
 ///
 /// Throws an [ArgumentError] if [location] isn't a [String] or a [Uri].
 String _locationToString(location) {
   if (location is String) return location;
   if (location is Uri) return location.toString();
 
   throw new ArgumentError('Response location must be a String or Uri, was '
       '"$location".');
 }