app.js

var transformAsync = function(objects, map, data) {
  console.log('-----------------------------------');
  console.log('Function transformAsync is started.');
  var keys = Object.keys(map);
  async.each(objects, function(object, done) {
    console.log('------------------------------------------------------------');
    console.log('Processing object: %s', util.inspect(object, { depth: null }));
    console.log('------------------------------------------------------------');
    async.each(keys, function(key) {
      if(typeof map[key] === 'object') {
        var nestedKeys = Object.keys(map[key]);
        async.each(nestedKeys, function(nestedKey) {
          var nestedValue = map[key][nestedKey];
          if(nestedValue === object.key) {
            console.log('Nested value is %s:', nestedValue);
            console.log('This value (%s) has been changed to %s:', nestedValue, object.val);
            map[key][nestedKey] = object.val;
          }
        });
      } else {
        var value = map[key];
        if(value === object.key) {
          console.log('Value is %s:', value);
          console.log('This value (%s) has been changed to %s:', value, object.val);
          map[key] = object.val;
        }
      }
    });
  });
  console.log('Function async is ended.');
  console.log('--------------------------------------');
  data(null, map);
};

transformAsync(dataObject, mapObject, function(err, data) {
  console.log('Wellcome to transformAsync callback!');

  console.log(util.inspect(data, { depth: null }));

  console.log('SUCCESS!');
});