Add Backbone.Deferred, utils.ajax and Backbone.resolveDeferred.

Author: paulmillr

lib/dom-utils.js

@@ -1,3 +1,5 @@
+// Usage:
+//   utils.matchesSelector(div, '.something');
 utils.matchesSelector = (function() {
   // Suffix.
   var sfx = 'MatchesSelector';
@@ -15,3 +17,65 @@ utils.matchesSelector = (function() {
     return element[name](selector);
   };
 })();
+
+// Make AJAX request to the server.
+// Usage:
+//   var callback = function(error, data) {console.log('Done.', error, data);};
+//   ajax({url: 'url', method: 'PATCH', data: 'data'}, callback);
+utils.ajax = (function() {
+  var xmlRe = /^(?:application|text)\/xml/;
+  var jsonRe = /^application\/json/;
+
+  var getData = function(accepts, xhr) {
+    if (accepts == null) accepts = xhr.getResponseHeader('content-type');
+    if (xmlRe.test(accepts)) {
+      return xhr.responseXML;
+    } else if (jsonRe.test(accepts)) {
+      return JSON.parse(xhr.responseText);
+    } else {
+      return xhr.responseText;
+    }
+  };
+
+  var isValid = function(xhr) {
+    return (xhr.status >= 200 && xhr.status < 300) ||
+      (xhr.status === 304) ||
+      (xhr.status === 0 && window.location.protocol === 'file:')
+  };
+
+  var end = function(xhr, options, promise) {
+    return function() {
+      if (xhr.readyState !== 4) return;
+
+      var status = xhr.status;
+      var data = getData(options.headers && options.headers.Accept, xhr);
+
+      // Check for validity.
+      if (isValid(xhr)) {
+        if (options.success) options.success(data);
+        if (promise) utils.resolveDeferred(promise, true, [data, xhr]);
+      } else {
+        var error = new Error('Server responded with a status of ' + status);
+        error.code = status;
+        if (options.error) options.error(xhr, status, error);
+        if (promise) utils.resolveDeferred(promise, false, [xhr]);
+      }
+    }
+  };
+
+  return function(options) {
+    if (options == null) throw new Error('You must provide options');
+    if (options.method == null) options.method = 'GET';
+
+    var xhr = new XMLHttpRequest();
+    var promise = Backbone.Deferred && Backbone.Deferred();
+    if (options.credentials) options.withCredentials = true;
+    xhr.addEventListener('readystatechange', end(xhr, options, promise));
+    xhr.open(options.method, options.url, true);
+    if (options.headers) for (var key in options.headers) {
+      xhr.setRequestHeader(key, options.headers[key]);
+    }
+    xhr.send(options.data);
+    return promise;
+  };
+})();

lib/sync.js

@@ -79,6 +79,14 @@ var methodMap = {
 
 // Set the default implementation of `Backbone.ajax` to proxy through to `$`.
 // Override this if you'd like to use a different library.
-Backbone.ajax = function() {
+Backbone.ajax = Backbone.$ ? function() {
   return Backbone.$.ajax.apply(Backbone.$, arguments);
+} : utils.ajax;
+
+Backbone.Deferred = Backbone.$ ? function() {
+  return new Backbone.$.Deferred();
+} : null;
+
+Backbone.resolveDeferred = function(deferred, isResolved, args) {
+  return null;
 };