Add Resource package.

lib/src/io.dart

Index: lib/src/io.dart
diff --git a/lib/src/io.dart b/lib/src/io.dart
index 8237c0160f1493fb74e905797e4e8a3c5add4280..ba137962167a922709b62e2a01d8875ff00af62c 100644
--- a/lib/src/io.dart
+++ b/lib/src/io.dart
@@ -1,59 +1,90 @@
-// Copyright (c) 2015, 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.
-
-// dart:io based strategy for loading resources.
-
-import "dart:io" show File, HttpClient, HttpClientRequest, HttpClientResponse;
-import "dart:async" show Future, Stream;
-import "dart:convert" show Encoding, UTF8;
-import "package:typed_data/typed_buffers.dart" show Uint8Buffer;
-
-Stream<List<int>> readAsStream(Uri uri) async* {
-  if (uri.scheme == "file") {
-    yield* new File.fromUri(uri).openRead();
-    return;
-  }
-  if (uri.scheme == "http" || uri.scheme == "https") {
-    HttpClientResponse response = await _httpGet(uri);
-    yield* response;
-    return;
-  }
-  throw new UnsupportedError("Unsupported scheme: $uri");
-}
-
-Future<List<int>> readAsBytes(Uri uri) async {
-  if (uri.scheme == "file") {
-    return new File.fromUri(uri).readAsBytes();
-  }
-  if (uri.scheme == "http" || uri.scheme == "https") {
-    HttpClientResponse response = await _httpGet(uri);
-    Uint8Buffer buffer = new Uint8Buffer();
-    await for (var bytes in response) {
-      buffer.addAll(bytes);
-    }
-    return buffer.toList();
-  }
-  throw new UnsupportedError("Unsupported scheme: $uri");
-}
-
-Future<String> readAsString(Uri uri, Encoding encoding) async {
-  if (encoding == null) encoding = UTF8;
-  if (uri.scheme == "file") {
-    return new File.fromUri(uri).readAsString(encoding: encoding);
-  }
-  if (uri.scheme == "http" || uri.scheme == "https") {
-    HttpClientResponse response = await _httpGet(uri);
-    Uint8Buffer buffer = new Uint8Buffer();
-    await for (var bytes in response) {
-      buffer.addAll(bytes);
-    }
-    new String.fromCharCodes(buffer.toList());
-  }
-  throw new UnsupportedError("Unsupported scheme: $uri");
-}
-
-Future<HttpClientResponse> _httpGet(Uri uri) async {
-  HttpClientRequest request = await new HttpClient().getUrl(uri);
-  return await request.close();
-}
+// Copyright (c) 2015, 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.
+
+// dart:io based strategy for loading resources.
+
+import "dart:async" show Future, Stream;
+import "dart:convert" show Encoding, LATIN1, UTF8;
+import "dart:io" show
+    File, HttpClient, HttpClientResponse, HttpClientRequest, HttpHeaders;
+import "dart:typed_data" show Uint8List;
+import "package:typed_data/typed_buffers.dart" show Uint8Buffer;
+
+/// Read the bytes of a URI as a stream of bytes.
+Stream<List<int>> readAsStream(Uri uri) async* {
+  if (uri.scheme == "file") {
+    yield* new File.fromUri(uri).openRead();
+    return;
+  }
+  if (uri.scheme == "http" || uri.scheme == "https") {
+    HttpClientResponse response = await _httpGet(uri);
+    yield* response;
+    return;
+  }
+  if (uri.scheme == "data") {
+    yield uri.data.contentAsBytes();
+    return;
+  }
+  throw new UnsupportedError("Unsupported scheme: $uri");
+}
+
+/// Read the bytes of a URI as a list of bytes.
+Future<List<int>> readAsBytes(Uri uri) async {
+  if (uri.scheme == "file") {
+    return new File.fromUri(uri).readAsBytes();
+  }
+  if (uri.scheme == "http" || uri.scheme == "https") {
+    HttpClientResponse response = await _httpGet(uri);
+    Uint8Buffer buffer = new Uint8Buffer();
+    await for (var bytes in response) {
+      buffer.addAll(bytes);
+    }
+    return buffer.toList();
+  }
+  if (uri.scheme == "data") {
+    return uri.data.contentAsBytes();
+  }
+  throw new UnsupportedError("Unsupported scheme: $uri");
+}
+
+/// Read the bytes of a URI as a string.
+Future<String> readAsString(Uri uri, Encoding encoding) async {
+  if (uri.scheme == "file") {
+    if (encoding == null) encoding = UTF8;
+    return new File.fromUri(uri).readAsString(encoding: encoding);
+  }
+  if (uri.scheme == "http" || uri.scheme == "https") {
+    HttpClientRequest request = await new HttpClient().getUrl(uri);
+    // Prefer text/plain, text/* if possible, otherwise take whatever is there.
+    request.headers.set(HttpHeaders.ACCEPT, "text/plain, text/*, */*");
+    if (encoding != null) {
+      request.headers.set(HttpHeaders.ACCEPT_CHARSET, encoding.name);
+    }
+    HttpClientResponse response = await request.close();
+    encoding ??= Encoding.getByName(response.headers.contentType?.charset);
+    if (encoding == null || encoding == LATIN1) {
+      // Default to LATIN-1 if no encoding found.
+      // Special case LATIN-1 since it is common and doesn't need decoding.
+      int length = response.contentLength;
+      if (length < 0) length = 0;
+      Uint8Buffer buffer = new Uint8Buffer(length);
+      await for (var bytes in response) {
+        buffer.addAll(bytes);
+      }
+      var byteList = new Uint8List.view(buffer.buffer, 0, buffer.length);
+      return new String.fromCharCodes(byteList);
+    }
+    return response.transform(encoding.decoder).join();
+  }
+  if (uri.scheme == "data") {
+    return uri.data.contentAsString(encoding: encoding);
+  }
+  throw new UnsupportedError("Unsupported scheme: $uri");
+}
+
+Future<HttpClientResponse> _httpGet(Uri uri) async {
+  HttpClientRequest request = await new HttpClient().getUrl(uri);
+    request.headers.set(HttpHeaders.ACCEPT, "application/octet-stream, */*");
+  return request.close();
+}