freecodecamp crawler using promise, generator and coroutine

index.js

var request = require('request-promise');
var co = require('co');
var fs = require('fs');
var cheerio = require('cheerio');
var dateFormat = require('dateformat');

var usernames = ['jd615645', 'jayhung97724'];

var fcc_info = [];

var parser_time = dateFormat(new Date(), 'yyyy-mm-dd HH:MM:ss');

co(function*(){
	var fcc_info = yield usernames.map(function(name) {
		return request({
			url: 'https://www.freecodecamp.com/' + name,
			method: 'GET'
		});
	});
	return fcc_info.map(function(data,i) {
		
		$ = cheerio.load(data);
		var source = parseInt($('h1.text-primary').text().match(/[0-9]{2}/));
		var challenges = $('table tr');
		var challenge = [];

		for (var j = 0; j < challenges.length; j++) {
			var name = $(challenges[j]).find('td:first-child').text();
			var time = $(challenges[j]).find('td:nth-child(2)').text();
			challenge.push({
				name: name,
				time: time
			});
		}
		return {
			username: usernames[i],
			source: source,
			challenges: challenge
		};
	});
}).then(
	fcc_info => fs.writeFileSync("result.json", JSON.stringify(fcc_info)),
	err => console.error(err)
);

package.json

{
  "name": "try_promise",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "cheerio": "^0.20.0",
    "co": "^4.6.0",
    "dateformat": "^1.0.12",
    "request-promise": "^3.0.0"
  }
}