Better promise handling with requests.

Fix #49

- https://trello.com/card/request-promises-should-reject/51a8c7c06d8a1a70030000dc/16
- https://trello.com/card/consumers-services-should-surface-errors-in-request-and-event-handlers/51a8c7c06d8a1a70030000dc/18
- https://trello.com/card/behavior-of-card-when-capability-is-unfulfilled-currently-never-fulfills-rejects-when-making-a-request/51a8c7c06d8a1a70030000dc/2

History.md

@@ -1,11 +1,45 @@
 ### 0.2.0
 
+- custom services will have `error` invoked if the environment did not provide
+  the capability.  For example:
+```js
+  // environment
+  var conductor = new Conductor(),
+  // both services exist
+  conductor.services.fulfilledCapability = Conductor.Oasis.Service;
+  conductor.services.unfulfilledCapability = Conductor.Oasis.Service;
+  // but only one capability is provided to the card
+  conductor.load("unfulfilled_capability_card.js", 1, { capabilities: ['fulfilledCapability']});
+
+  // sandbox
+  var card = Conductor.card({
+    consumers: {
+      fulfilledCapability: Conductor.Oasis.Consumer.extend({
+        error: function () {
+          // not invoked
+        }
+      }),
+      unfulfilledCapability: Conductor.Oasis.Consumer.extend({
+        error: function () {
+          // invoked
+        }
+      })
+    }
+  });
+```
+- added partial support for IE8.  `postMessage` is too slow for large messages
+  (eg transferring jQuery using xhr service) for IE8 to be considered fully
+  supported.
 - added support for IE10, IE9, Firefox, Safari.
 - rsvp upgraded to 2.0.0.
 - oasis upgraded.
 
 ##### Breaking Changes
 
+- Request handlers are no longer passed a resolver.  Instead they may return
+  values directly or return promises if the values need to be retrieved
+  asynchronously.  Returned promises may reject, which will cause promise
+  rejection to the corresponding service or consumer.
 - cards are no longer promise entities, but they have a promise property that
   is resolved on sandbox readiness.  `card.then` → `card.promise.then`.
 - iframe sandboxes are now started on `appendTo` and not on `load`.  This means
@@ -17,6 +51,7 @@
   This file does not need to end in `html` but it does need to be served with an
   html content type.
 
-### 0.1.0 / 15 June 2013
+### 0.1.0
+*15 July 2013*
 
 Initial version.

dist/conductor.amd.js

@@ -858,18 +858,16 @@ define("conductor.js-0.2.0",
     Conductor.metadataConsumer = function(card) {
       var options = card.options;
 
-      options.requests.metadataFor = function(resolver, name) {
+      options.requests.metadataFor = function(name) {
         if (name === '*') {
-          var promises = [], names = [], defered;
+          var values = [], names = [], defered;
 
           for (var metadataName in options.metadata) {
-            defered = Conductor.Oasis.RSVP.defer();
-            card.metadata[metadataName].call(card, defered);
-            promises.push(defered.promise);
+            values.push(card.metadata[metadataName].call(card));
             names.push(metadataName);
           }
 
-          Conductor.Oasis.RSVP.all(promises).then(function(sources) {
+          return Conductor.Oasis.RSVP.all(values).then(function(sources) {
             var metadata = {};
 
             for (var i = 0; i < sources.length; i++) {
@@ -879,11 +877,11 @@ define("conductor.js-0.2.0",
               }
             }
 
-            resolver.resolve(metadata);
+            return metadata;
           });
 
         } else {
-          card.metadata[name].call(card, resolver);
+          return card.metadata[name].call(card);
         }
       };
 
@@ -1153,21 +1151,25 @@ define("conductor.js-0.2.0",
 
     Conductor.XHRService = Conductor.Oasis.Service.extend({
       requests: {
-        get: function(promise, url) {
-          var xhr = new XMLHttpRequest(),
-              resourceUrl = PathUtils.cardResourceUrl(this.sandbox.options.url, url);
-
-          xhr.onreadystatechange = function (a1, a2, a3, a4) {
-            if (this.readyState === 4) {
-              if (this.status === 200) {
-                promise.resolve(this.responseText);
-              } else {
-                promise.reject({status: this.status});
+        get: function(url) {
+          var service = this;
+
+          return new Conductor.Oasis.RSVP.Promise(function (resolve, reject) {
+            var xhr = new XMLHttpRequest(),
+                resourceUrl = PathUtils.cardResourceUrl(service.sandbox.options.url, url);
+
+            xhr.onreadystatechange = function (a1, a2, a3, a4) {
+              if (this.readyState === 4) {
+                if (this.status === 200) {
+                  resolve(this.responseText);
+                } else {
+                  reject({status: this.status});
+                }
               }
-            }
-          };
-          xhr.open("get", resourceUrl, true);
-          xhr.send();
+            };
+            xhr.open("get", resourceUrl, true);
+            xhr.send();
+          });
         }
       }
     });