feat(data): Add Model#eachAttribute (#118)

lib/data/model.js

@@ -27,6 +27,14 @@ import {
  */
 export default class Model {
 
+  /**
+   * An internal cache of all attributes defined on this model.
+   * @type {Array}
+   * @static
+   * @private
+   */
+  static _attributesCache = null;
+
   /**
    * The type of the Model class. This string is used as the container name for
    * the model, as well as in several other areas of Denali (i.e. serializers,
@@ -325,6 +333,29 @@ export default class Model {
     return this.container.lookup(`model:${ type }`);
   }
 
+  /**
+   * Call the supplied callback function for each attribute on this model,
+   * passing in the attribute name and attribute instance.
+   *
+   * @method eachAttribute
+   * @static
+   * @param fn {Function}
+   * @return {Array}
+   */
+  static eachAttribute(fn) {
+    if (!this._attributesCache) {
+      this._attributesCache = [];
+      for (let key in this) {
+        if (this[key] && this[key].isAttribute) {
+          this._attributesCache.push(key);
+        }
+      }
+    }
+    return this._attributesCache.map((attributeName) => {
+      return fn(attributeName, this[attributeName]);
+    });
+  }
+
   /**
    * Lookup a model class by type.
    *