live updated dirty tracking (attrs and rels)

addon/models/resource.js

@@ -103,6 +103,21 @@ const Resource = Ember.Object.extend(ResourceOperationsMixin, {
   */
   _attributes: null,
 
+  /**
+    Array of changed attribute keys.
+
+    The Actual changed values (previous, changed) are stored on _attributes,
+    but we can not use that object or it's keys to create computed properties
+    that respond to changes (i.e. no live isDirty property).
+    This array is a simple list of attributes that are not in their original
+    state, and can be used to track the (dirty-)state of the resource.
+
+    @protected
+    @property _changedAttributes
+    @type Array
+  */
+  _changedAttributes: null,
+
   /**
     Hash of relationships that were changed
 
@@ -112,6 +127,15 @@ const Resource = Ember.Object.extend(ResourceOperationsMixin, {
   */
   _relationships: null,
 
+  /**
+   Array of changed relationship keys. Same use as _changedAttributes.
+
+   @protected
+   @property _changedRelationships
+   @type Array
+  */
+  _changedRelationships: null,
+
   /**
     Flag for new instance, e.g. not persisted
 
@@ -139,7 +163,7 @@ const Resource = Ember.Object.extend(ResourceOperationsMixin, {
   */
   _updateRelationshipsData(relation, ids) {
     if (!Array.isArray(ids)) {
-      this._updateToOneRelationshipData(relation, ids); 
+      this._updateToOneRelationshipData(relation, ids);
     } else {
       let existing = this._existingRelationshipData(relation);
       if (!existing.length) {
@@ -178,7 +202,7 @@ const Resource = Ember.Object.extend(ResourceOperationsMixin, {
   */
   _replaceRelationshipsData(relation, ids) {
     if (!Array.isArray(ids)) {
-      this._updateToOneRelationshipData(relation, ids); 
+      this._updateToOneRelationshipData(relation, ids);
     } else {
       let existing = this._existingRelationshipData(relation);
       if (!existing.length) {
@@ -300,6 +324,19 @@ const Resource = Ember.Object.extend(ResourceOperationsMixin, {
         ref.added.push({type: pluralize(relation), id: id});
       }
     }
+
+    // Track relationship changes
+    if (!this.get('isNew')) {
+      if (!this.get('_changedRelationships')) {
+        this.set('_changedRelationships', Ember.A([]));
+      }
+
+      if (!Ember.isEmpty(ref.added) ||
+          !Ember.isEmpty(ref.removals) ||
+          !Ember.isEmpty(ref.changed)) {
+        this.get('_changedRelationships').pushObject(relation);
+      }
+    }
   },
 
   /**
@@ -364,6 +401,18 @@ const Resource = Ember.Object.extend(ResourceOperationsMixin, {
         ref.removals.pushObject({ type: pluralize(relation), id: id });
       }
     }
+
+    // Track relationship changes.
+    if (!this.get('isNew')) {
+      if (!this.get('_changedRelationships')) {
+        this.set('_changedRelationships', Ember.A([]));
+      }
+      if (!Ember.isEmpty(ref.added) ||
+          !Ember.isEmpty(ref.removals) ||
+          !Ember.isEmpty(ref.previous)) {
+        this.get('_changedRelationships').removeObject(relation);
+      }
+    }
   },
 
   /**
@@ -455,6 +504,7 @@ const Resource = Ember.Object.extend(ResourceOperationsMixin, {
         delete this._attributes[attr];
       }
     }
+    this.set('_changedAttributes', Ember.A([]));
   },
 
   /**
@@ -499,6 +549,7 @@ const Resource = Ember.Object.extend(ResourceOperationsMixin, {
         delete this._relationships[attr];
       }
     }
+    this.set('_changedRelationships', Ember.A([]));
   },
 
   /**

addon/utils/attr.js

@@ -63,18 +63,49 @@ export default function attr(type = 'any', mutable = true) {
 
     set: function (key, value) {
       const lastValue = this.get('attributes.' + key);
+      // Don't allow set on immutable values.
       if (!_mutable) {
         return immutableValue(key, value, lastValue);
       }
+      // Don't do anything if same value is set.
       if (value === lastValue) { return value; }
+
+      // Check value type.
       assertType.call(this, key, value);
+
+      // Set value.
       this.set('attributes.' + key, value);
+
+      // Track changes.
+      // Only on non-isNew resources, which are 'dirty' be default
       if (!this.get('isNew')) {
+        // Initialize tracking object and array for this attribute.
         this._attributes[key] = this._attributes[key] || {};
+        if (!this.get('_changedAttributes')) {
+          this.set('_changedAttributes', Ember.A([]));
+        }
+
+        // Track change(d key) and store previous/changed value.
+        // We (Ember.)Copy values to `previous` and `changed` to prevent both
+        // being a reference to the same object (and thus never showing up on
+        // computed property 'changedAttributes')
         if (this._attributes[key].previous === undefined) {
+          // Value changed for the first time.
           this._attributes[key].previous = Ember.copy(lastValue, true);
+          this.get('_changedAttributes').pushObject(key);
+        } else {
+          // Value changed again.
+          if (this._attributes[key].previous === value) {
+            // Value reverted to previous. No longer dirty. Remove from tracking.
+            this.get('_changedAttributes').removeObject(key);
+          } else if (this.get('_changedAttributes').indexOf(key) === -1){
+            // Value changed again, wasn't tracked anymore. Track it.
+            this.get('_changedAttributes').pushObject(key);
+          }
         }
+
         this._attributes[key].changed = Ember.copy(value, true);
+
         let service = this.get('service');
         if (service) {
           service.trigger('attributeChanged', this);