Properly specify Content-Transfer-Encoding.

lib/src/multipart_request.dart

 // Copyright (c) 2013, 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:convert';
 import 'dart:math';
 
 import 'base_request.dart';
 import 'byte_stream.dart';
 import 'multipart_file.dart';
 import 'utils.dart';
 
 final _newlineRegExp = new RegExp(r"\r\n|\r|\n");
 
 /// A `multipart/form-data` request. Such a request has both string [fields],
 /// which function as normal form fields, and (potentially streamed) binary
 /// [files].
 ///
 /// This request automatically sets the Content-Type header to
-/// `multipart/form-data` and the Content-Transfer-Encoding header to `binary`.
-/// These values will override any values set by the user.
+/// `multipart/form-data`. This value will override any value set by the user.
 ///
 ///     var uri = Uri.parse("http://pub.dartlang.org/packages/create");
 ///     var request = new http.MultipartRequest("POST", url);
 ///     request.fields['user'] = 'nweiz@google.com';
 ///     request.files.add(new http.MultipartFile.fromFile(
 ///         'package',
 ///         new File('build/package.tar.gz'),
 ///         contentType: new MediaType('application', 'x-tar'));
 ///     request.send().then((response) {
 ///       if (response.statusCode == 200) print("Uploaded!");
@@ skipping 45 matching lines @@
     throw new UnsupportedError("Cannot set the contentLength property of "
         "multipart requests.");
   }
 
   /// Freezes all mutable fields and returns a single-subscription [ByteStream]
   /// that will emit the request body.
   ByteStream finalize() {
     // TODO(nweiz): freeze fields and files
     var boundary = _boundaryString();
     headers['content-type'] = 'multipart/form-data; boundary="$boundary"';
-    headers['content-transfer-encoding'] = 'binary';
     super.finalize();
 
     var controller = new StreamController<List<int>>(sync: true);
 
     void writeAscii(String string) {
       controller.add(UTF8.encode(string));
     }
 
     writeUtf8(String string) => controller.add(UTF8.encode(string));
     writeLine() => controller.add([13, 10]); // \r\n
@@ skipping 29 matching lines @@
     104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,
     119, 120, 121, 122
   ];
 
   /// Returns the header string for a field. The return value is guaranteed to
   /// contain only ASCII characters.
   String _headerForField(String name, String value) {
     var header =
         'content-disposition: form-data; name="${_browserEncode(name)}"';
     if (!isPlainAscii(value)) {
-      header = '$header\r\ncontent-type: text/plain; charset=utf-8';
+      header = '$header\r\n'
+          'content-type: text/plain; charset=utf-8\r\n'
+          'content-transfer-encoding: binary\r\n';
     }
     return '$header\r\n\r\n';
   }
 
   /// Returns the header string for a file. The return value is guaranteed to
   /// contain only ASCII characters.
   String _headerForFile(MultipartFile file) {
     var header = 'content-type: ${file.contentType}\r\n'
       'content-disposition: form-data; name="${_browserEncode(file.field)}"';
 
@@ skipping 16 matching lines @@
   /// Returns a randomly-generated multipart boundary string
   String _boundaryString() {
     var prefix = "dart-http-boundary-";
     var list = new List<int>.generate(_BOUNDARY_LENGTH - prefix.length,
         (index) =>
             _BOUNDARY_CHARACTERS[_random.nextInt(_BOUNDARY_CHARACTERS.length)],
         growable: false);
     return "$prefix${new String.fromCharCodes(list)}";
   }
 }