create variants

gistfile1.js

async.waterfall(
  [
    function getVariants(callback){
      //get variants, pass them to the callback
      return callback(null, variants);
    },
    function(variants, callback){
      //if variants is an array, you can nest more async functions
      async.map(variants, function(variant, cb){
        //create variant
        cb(null, result);
      }, callback);
    },
    function(results, callback){
      //at this point, you will have all the results, you can send them back to millicore
      return callback();
    }
  ], function(err){
  }
)