Example of working with arrays

promiseArray.js

const Promise = require('bluebird')

const items = {
    employers: [
        {
            name: 'qqqq',
            cost: 1111,
        },
        {
            name: 'weferf',
            cost: 2222,
        }
    ]
}

//  Promise.map
const getOne = async employers => {
    let i = 0

    return await Promise.map(employers, employer => {
        const resp = {
            i,
            properties: employer
        }
    
        i++
    
        return resp
    }, { concurrency: 1 })
}
// Will return a new array
console.log('getOne: ', getOne(items.employers))

//  Promise.filter
const filterEmployers = async (employers, filter) => {
    return await Promise.filter(employers, employer => employer.cost === filter)
}
// Will return the filtered array
console.log('res2: ', getDuo(items.employers, 1111))

//  array find
const findOne = (employers, find) => employers.find(employer => employer.cost === find)

// return object or undefined
console.log('findOne: ', findOne(items.employers, 1111))