Meteor.methods({

  'Listing.update': function(docId, data) {

    var doc = db.listings.findOne({_id: docId}) || {};

    if (doc.userId !== this.userId) {
      throw new Meteor.Error(504, "You don't own post");
    }

    // ensure data is the type we expect
    check(data, {
      title: String,
      desc: String
    });

    return db.listings.update(docId, {$set: data});
  }

});