async_await_sample.js

'use strict'

const sleep = someFunction => {
    return new Promise(resolve => {
        setTimeout(() => {
            resolve(someFunction())        
        }, 5000)
    })
}

const response = async params => {
    return await sleep(() => { return params })
}

const isValidParams = params => {
    if (!params.id) {
        return false
    }

    return true
}

const searchPriceById = async id => {
    return await sleep(() => { return 1000 })
}

const getPrice = async () => {
    const resp = await response({ 'id': 'abc123' })
    if (!isValidParams(resp)) {
        throw new Error('"id" must be included to params.')
    }
    const itemPrice = await searchPriceById(resp.id)
    console.log(itemPrice)
}

getPrice().catch(error => {
    console.log(error)
})