Adding ease-of-use methods to HttpRequest.

tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate

 // 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.
 
 part of html;
 
 /**
  * A utility for retrieving data from a URL.
  *
  * HttpRequest can be used to obtain data from http, ftp, and file
@@ skipping 43 matching lines @@
    * * The `Access-Control-Allow-Origin` header of `url` cannot contain a wildcard (*).
    * * The `Access-Control-Allow-Credentials` header of `url` must be set to true.
    * * If `Access-Control-Expose-Headers` has not been set to true, only a subset of all the response headers will be returned when calling [getAllRequestHeaders].
    *
    * See also: [authorization headers](http://en.wikipedia.org/wiki/Basic_access_authentication).
    */
   factory $CLASSNAME.getWithCredentials(String url,
       onComplete($CLASSNAME request)) =>
       _HttpRequestUtils.get(url, onComplete, true);
 
+
+  /**
+   * Creates a URL get request for the specified `url`.
+   *
+   * The server response must be a `text/` mime type for this request to
+   * succeed.

[Emily Fortuna, 2013/01/31 01:04:15]

might say in the docs how this is different from the request method.

[blois, 2013/01/31 18:58:12]

Done.

+   */
+  static Future<String> getString(String url,
+      {bool withCredentials}) {
+    return request(url, withCredentials: withCredentials).then(
+      (xhr) {

[Jennifer Messerly, 2013/01/31 04:12:17]

maybe format this as:
(xhr) => xhr.responseText
?

[blois, 2013/01/31 18:58:12]

Done.

+        return xhr.responseText;
+      });
+  }
+
+  /**
+   * Creates a URL request for the specified `url`.

[Jennifer Messerly, 2013/01/31 04:12:17]

[url] ?

[blois, 2013/01/31 18:58:12]

Done. Was mostly just following formatting from existing docs.

+   *
+   * By default this will do an HTTP GET request, this can be overridden with
+   * [method].
+   *
+   * The Future is completed when the response is available.
+   */

[Emily Fortuna, 2013/01/31 01:04:15]

since this method replaces the functionality of the HttpRequest.get()
constructor, should we remove that constructor? If so, we should transfer the
docs from the getWithCredentials constructor here, too.

[Jennifer Messerly, 2013/01/31 04:12:17]

I was wondering that too. They take callbacks instead of Futures, but return a
new object, but you don't really want to use this object until the callback. A
bit strange :) I think these new static methods are better.

[blois, 2013/01/31 18:58:12]

The primary benefit of the factories is that you can use progress events on them
if desired. But these methods should be considered helpers and do not need to
address all scenarios.

I was a bit hesitant at first about the new APIs, so was leaving the old one in,
but now I think they should just be removed.

Added an onProgress named param to cover the progress scenario as well.

+  static Future<HttpRequest> request(String url,
+      {String method, bool withCredentials, String responseType, sendData}) {
+    var completer = new Completer<String>();
+
+    var xhr = new HttpRequest();
+    if (method == null) {
+      method = 'GET';
+    }
+    xhr.open(method, url, true);
+
+    if (withCredentials != null) {
+      xhr.withCredentials = withCredentials;
+    }
+
+    if (responseType != null) {
+      xhr.responseType = responseType;
+    }
+
+    xhr.onLoad.listen((e) {
+      if (xhr.status >= 200 && xhr.status < 300 ||
+          xhr.status == 304 ) {
+        completer.complete(xhr);
+      } else {
+        completer.completeError(e);
+      }
+    });
+
+    xhr.onError.listen((e) {
+      completer.completeError(e);
+    });
+
+    if (sendData != null) {
+      xhr.send(sendData);
+    } else {
+      xhr.send();
+    }
+
+    return completer.future;
+  }
+
 $!MEMBERS
 }