An ampersand model that replaces the idAttribtue in isNew with fetched property that is set after the model performs a get/fetch, this property can also be used for waitFor.

Fetched Model

var Model = require('ampersand-model');
var _ = require('lodash');

module.exports = Model.extend({
    constructor: function(){
        Model.apply(this, arguments);
        _.bindAll(this, 'onSync');
        this.on('sync', this.onSync);
    },
    isNew: function(){
        return !this.fetched;
    },
    session:{
        fetched: ['boolean', true, false],
    },
    onSync: function (model, resp, options) {
        if (options.xhr.method === "GET") {
            this.fetched = true;
        }
    }
});