Running CRUD methods in a remote method for a loopback model

coupon.js

module.exports = function(Coupon) {
	Coupon.status = function(cb) {
		var currentDate = new Date();
		Coupon.count({expiredDate: {gt : currentDate}}, function(err, nbCoupons) {
			return cb(err, nbCoupons);
		});
	};
	Coupon.expirationStatus = function(couponId, cb) {
		var currentDate = new Date();
		Coupon.findById(couponId, function(err, instance) {
			if(err) throw err;
			if(instance && instance.expiredDate > currentDate) return cb(null, true);
			else return cb(null, false);
		});
	};
	Coupon.remoteMethod(
		'status',
		{
			http:{path: '/status', verb:'get'},
			returns: {arg : 'NumberCouponNotExpired', type: 'string'}
		}
	);
	Coupon.remoteMethod(
		'expirationStatus',
		{
			http: {path: '/getExpirationStatus', verb: 'get'},
			accepts: {arg: 'id', type: 'any', http: {source: 'query'}},
			returns : {arg: 'status', type: 'string'}
		}
	);
};