var async = require('async');
_ = require('lodash');

var DATA = [
	{ id: 1, name: 'One', group: 'One' },
	{ id: 4, name: 'Trr', group: 'Two' },
	{ id: 3, name: 'Rtt', group: 'Three' },
	{ id: 4, name: 'Vbb', group: 'Two' },
	{ id: 8, name: 'Ncc', group: 'One' },
	{ id: 6, name: 'Onaaa', group: 'Three' },
	{ id: 7, name: 'Opaa', group: 'One' }
];

var data = [], count, err;

function group(data) {
	var hash = {}, arr = [];
	data.forEach(function (o) {
		if (!hash[o.group])
			hash[o.group] = {
				count: 0
			};
		hash[o.group].count++;
		hash[o.group].name = o.name;
		hash[o.group].id = o.id;
	});
	Object.keys(hash).forEach(function (val) {
		arr.push(hash[val]);
	});
	return arr;
}
var res = {};

var tasks = {
	group: function (callback) {
		data = group(DATA);
		res = { group: 1 };
		callback(null, data);
	},
	sort: function (callback) {
		data = _.sortBy(data, function (o) {
			return o.id;
		});
		res.sort = 1;
		callback(null, data);
	},
	count: function(callback){
		count = data.length;
		callback(data, { count: 1});
	}
};

async.parallel(tasks, function (err, data) {
	console.info(JSON.stringify(data, null, 2));
});

///
{
  "group": [
    {
      "count": 3,
      "name": "Opaa",
      "id": 7
    },
    {
      "count": 2,
      "name": "Vbb",
      "id": 4
    },
    {
      "count": 2,
      "name": "Onaaa",
      "id": 6
    }
  ],
  "sort": [
    {
      "count": 2,
      "name": "Vbb",
      "id": 4
    },
    {
      "count": 2,
      "name": "Onaaa",
      "id": 6
    },
    {
      "count": 3,
      "name": "Opaa",
      "id": 7
    }
  ],
  "count": {
    "count": 1
  }
}