examples.js

/**
  The idea here is that all changes to your new object can be observed
 */
Ember.View.extend({
  model: Ember.StalkableObject.create(),
  saveModel: Ember.observer(function () {
    /** do some fancy stuff to save changes to your model */
  }, 'model.@properties')
});

Ember.View.extend({
  model: Ember.StalkableObject.create({ host: null, port: null }),
  saveModel: Ember.observer(function () {
    /** this will only be called when changes to the 'host' and 'port' are changed */
  }, 'model.@initProperties')
});

Ember.View.extend({
  model: App.MyStalkableModel.create(),
  saveModel: Ember.observer(function () {
    /** this will only be called when changes to the prototyped properties of App.MyStalkableModel are changed */
  }, 'model.@prototypeProperties')
});

Ember.View.extend({
  model: Ember.StalkableObject.create({ nonce: null }),
  saveModel: Ember.observer(function () {
    /** this will be called on changes any properties that are undefined at instantiation (i.e., excluding all the 
        stuff on Object, as well as "nonce", which we expect to change frequently.) */
  }, 'model.@ownProperties')
});

stalkable.js

/*jslint nomen:true */
/**
  "Stalkable" objects can be watched for any and all changes
	@author  Bryan Elliott <[email protected]>
*/
(function (global) {
	"use strict";
	var Ember = global.Ember;
	/**
		Detect whether an Object is using this Mixin
	*/
	Ember.Mixin.prototype.detectInstance = function (object) {
		/*jslint forin:true */
		var name,
			mixins = object[Ember.META_KEY].mixins;
		for (name in mixins) {
			if (this.detect(mixins[name])) {
				return true;
			}
		}
		return false;
	};
	/**
		Changes to Ember.CoreObject that enable property stalking via the pseudoproperties: "@properties", "@ownProperties", and "@prototypeProperties"
	*/
	Ember.Stalkable = Ember.Mixin.create({
		setUnknownProperty: function (key, value) {
			var ret = this._super.apply(this, arguments);
			this.observeNewProperty(key);
			return ret;
		},
		observeNewProperty: function (key, isProto) {
			var inst = this,
				isInit = inst.constructor.prototype.hasOwnProperty(key),
				clean,
				handler = function () {
					clean = !inst.modifiedProperties;
					if (clean) {
						inst.modifiedProperties = [ key ];
					} else {
						inst.modifiedProperties.push(key);
					}
					if (!isProto && !isInit) {
						inst.notifyPropertyChange("@ownProperties");
					} else if (isInit && !isProto) {
						inst.notifyPropertyChange("@initProperties");
					} else {
						inst.notifyPropertyChange("@prototypeProperties");
					}
					inst.notifyPropertyChange("@properties");
					if (clean) {
						delete inst.modifiedProperties;
					}
				};
			this.addObserver(key, this, handler);
			if (!isProto) { handler(); }
		},
		setProperties: function () {
			var ret;
			this.modifiedProperties = [];
			ret = this._super.apply(this, arguments);
			delete this.modifiedProperties;
			return ret;
		}
	});

	/**
		Small modification to CoreObject.create for Stalkables
	*/
	Ember.CoreObject.reopenClass({
		create: function () {
			/*jslint forin:true */
			var i, name, args, caught = {},
				ret = this._super.apply(this, arguments);
			if (Ember.Stalkable.detectInstance(ret)) {
				args = [].slice.apply(arguments);
				for (i = 0; i < args.length; i += 1) {
					for (name in args[i]) {
						if (!(args[i][name] instanceof Function)) {
							ret.observeNewProperty(name);
							caught[name] = true;
						}
					}
				}
				for (name in ret) {
					if (!caught[name]) {
						ret.observeNewProperty(name, true)
					}
				}
			}
			return ret;
		}
	});
	Ember.StalkableObject = Ember.Object.extend(Ember.Stalkable);
}(this));