1 files changed, 187 insertions, 0 deletions
diff --git a/remoting/webapp/xhr.js b/remoting/webapp/xhr.js
new file mode 100644
index 0000000..2a48077
--- /dev/null
+++ b/remoting/webapp/xhr.js
@@ -0,0 +1,187 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * @fileoverview
+ * Simple utilities for making XHRs more pleasant.
+ */
+
+'use strict';
+
+/** @suppress {duplicate} */
+var remoting = remoting || {};
+
+/** Namespace for XHR functions */
+/** @type {Object} */
+remoting.xhr = remoting.xhr || {};
+
+/**
+ * Takes an associative array of parameters and urlencodes it.
+ *
+ * @param {Object.<string>} paramHash The parameter key/value pairs.
+ * @return {string} URLEncoded version of paramHash.
+ */
+remoting.xhr.urlencodeParamHash = function(paramHash) {
+  var paramArray = [];
+  for (var key in paramHash) {
+    paramArray.push(encodeURIComponent(key) +
+                     '=' + encodeURIComponent(paramHash[key]));
+  }
+  if (paramArray.length > 0) {
+    return paramArray.join('&');
+  }
+  return '';
+};
+
+/**
+ * Execute an XHR GET asynchronously.
+ *
+ * @param {string} url The base URL to GET, excluding parameters.
+ * @param {function(XMLHttpRequest):void} onDone The function to call on
+ *     completion.
+ * @param {(string|Object.<string>)=} opt_parameters The request parameters,
+ *     either as an associative array, or a string.  If it is a string, do
+ *     not include the ? and be sure it is correctly URLEncoded.
+ * @param {Object.<string>=} opt_headers Additional headers to include on the
+ *     request.
+ * @param {boolean=} opt_withCredentials Set the withCredentials flags in the
+ *     XHR.
+ * @return {XMLHttpRequest} The request object.
+ */
+remoting.xhr.get = function(url, onDone, opt_parameters, opt_headers,
+                            opt_withCredentials) {
+  return remoting.xhr.doMethod('GET', url, onDone, opt_parameters,
+                               opt_headers, opt_withCredentials);
+};
+
+/**
+ * Execute an XHR POST asynchronously.
+ *
+ * @param {string} url The base URL to POST, excluding parameters.
+ * @param {function(XMLHttpRequest):void} onDone The function to call on
+ *     completion.
+ * @param {(string|Object.<string>)=} opt_parameters The request parameters,
+ *     either as an associative array, or a string.  If it is a string, be
+ *     sure it is correctly URLEncoded.
+ * @param {Object.<string>=} opt_headers Additional headers to include on the
+ *     request.
+ * @param {boolean=} opt_withCredentials Set the withCredentials flags in the
+ *     XHR.
+ * @return {XMLHttpRequest} The request object.
+ */
+remoting.xhr.post = function(url, onDone, opt_parameters, opt_headers,
+                             opt_withCredentials) {
+  return remoting.xhr.doMethod('POST', url, onDone, opt_parameters,
+                               opt_headers, opt_withCredentials);
+};
+
+/**
+ * Execute an XHR DELETE asynchronously.
+ *
+ * @param {string} url The base URL to DELETE, excluding parameters.
+ * @param {function(XMLHttpRequest):void} onDone The function to call on
+ *     completion.
+ * @param {(string|Object.<string>)=} opt_parameters The request parameters,
+ *     either as an associative array, or a string.  If it is a string, be
+ *     sure it is correctly URLEncoded.
+ * @param {Object.<string>=} opt_headers Additional headers to include on the
+ *     request.
+ * @param {boolean=} opt_withCredentials Set the withCredentials flags in the
+ *     XHR.
+ * @return {XMLHttpRequest} The request object.
+ */
+remoting.xhr.remove = function(url, onDone, opt_parameters, opt_headers,
+                             opt_withCredentials) {
+  return remoting.xhr.doMethod('DELETE', url, onDone, opt_parameters,
+                               opt_headers, opt_withCredentials);
+};
+
+/**
+ * Execute an XHR PUT asynchronously.
+ *
+ * @param {string} url The base URL to PUT, excluding parameters.
+ * @param {function(XMLHttpRequest):void} onDone The function to call on
+ *     completion.
+ * @param {(string|Object.<string>)=} opt_parameters The request parameters,
+ *     either as an associative array, or a string.  If it is a string, be
+ *     sure it is correctly URLEncoded.
+ * @param {Object.<string>=} opt_headers Additional headers to include on the
+ *     request.
+ * @param {boolean=} opt_withCredentials Set the withCredentials flags in the
+ *     XHR.
+ * @return {XMLHttpRequest} The request object.
+ */
+remoting.xhr.put = function(url, onDone, opt_parameters, opt_headers,
+                             opt_withCredentials) {
+  return remoting.xhr.doMethod('PUT', url, onDone, opt_parameters,
+                               opt_headers, opt_withCredentials);
+};
+
+/**
+ * Execute an arbitrary HTTP method asynchronously.
+ *
+ * @param {string} methodName The HTTP method name, e.g. "GET", "POST" etc.
+ * @param {string} url The base URL, excluding parameters.
+ * @param {function(XMLHttpRequest):void} onDone The function to call on
+ *     completion.
+ * @param {(string|Object.<string>)=} opt_parameters The request parameters,
+ *     either as an associative array, or a string.  If it is a string, be
+ *     sure it is correctly URLEncoded.
+ * @param {Object.<string>=} opt_headers Additional headers to include on the
+ *     request.
+ * @param {boolean=} opt_withCredentials Set the withCredentials flags in the
+ *     XHR.
+ * @return {XMLHttpRequest} The XMLHttpRequest object.
+ */
+remoting.xhr.doMethod = function(methodName, url, onDone,
+                                 opt_parameters, opt_headers,
+                                 opt_withCredentials) {
+  /** @type {XMLHttpRequest} */
+  var xhr = new XMLHttpRequest();
+  xhr.onreadystatechange = function() {
+    if (xhr.readyState != 4) {
+      return;
+    }
+    onDone(xhr);
+  };
+
+  var parameterString = '';
+  if (typeof(opt_parameters) === 'string') {
+    parameterString = opt_parameters;
+  } else if (typeof(opt_parameters) === 'object') {
+    parameterString = remoting.xhr.urlencodeParamHash(opt_parameters);
+  } else if (opt_parameters === undefined) {
+    // No problem here. Do nothing.
+  } else {
+    throw 'opt_parameters must be string or associated array.';
+  }
+
+  var useBody = (methodName == 'POST') || (methodName == 'PUT');
+
+  if (!useBody && parameterString != '') {
+    url = url + '?' + parameterString;
+  }
+
+  xhr.open(methodName, url, true);
+  if (methodName == 'POST') {
+    xhr.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
+  }
+  // Add in request headers.
+  if (typeof(opt_headers) === 'object') {
+    for (var key in opt_headers) {
+      xhr.setRequestHeader(key, opt_headers[key]);
+    }
+  } else if (opt_headers === undefined) {
+    // No problem here. Do nothing.
+  } else {
+    throw 'opt_headers must be associative array.';
+  }
+
+  if (opt_withCredentials) {
+    xhr.withCredentials = true;
+  }
+
+  xhr.send(useBody ? parameterString : null);
+  return xhr;
+};