ReadJson.js

var each = require('foreach')
var fs = require('fs')
var content = fs.readFileSync('./data/static/teams.json', 'utf-8')
var ligas = {}
var equipos = JSON.parse(content)


each([equipos], function (value, key, array) {
    for (var i = 0; i < value.length; i++) {
		ligas = value.reduce(function (key, item) {
			key[item.liga] = key[item.liga] || []
			key[item.liga].push(item.equipo)
			return key
		}, Object.create(null))
    }
});

console.log(ligas)