Scrape website's flash card data and output HTML for markdown use

scraper.js

const got = require('got')
const cheerio = require('cheerio')
const Promise = require('bluebird')
const fs = Promise.promisifyAll(require('fs'))

const baseUrl = 'https://[nope].com/comptia-a-exam/flashcards/902-windows-operating-systems/pages'

function getFrontCard(baseUrl, startPageNumber = 1) {
  return got(`${baseUrl}/${startPageNumber}`)
    .then(res => {
      let $ = cheerio.load(res.body)
      let front = $('.front p').text()

      if (!front) throw Error('no card front found, bail!')

      return front
    })
}

function getBackCard(baseUrl, startPageNumber = 1) {
  let backInformation = []

  return got(`${baseUrl}/${startPageNumber}/back`)
    .then(res => {
      let $ = cheerio.load(res.body)

      let backAnswer = $('.back p').each(function(i, e) {
        backInformation[i] = $(this).text()
        if (!backInformation[0]) throw Error('no card back found, bail!')
      })

      return backInformation
    })
}

function buildCard(front, back) {
  return `
<details>
  <summary><b>${front}</b></summary>
  <h5>${back[0]}</h5>
  <p>${back[1]}</p>
</details>
 `
}

function writeToFile(card) {
  return fs.appendFileAsync('902-windows-operating-systems', card)
}

// recursive function continues until all pages are exhausted
function getNextPage(baseUrl, pageNum = 1) {
  console.log('fetching Page: ', pageNum);
  return Promise.delay(500).then(() => [
    getFrontCard(baseUrl, pageNum),
    getBackCard(baseUrl, pageNum)
  ])
  .spread(buildCard)
  .then(writeToFile)
  .then(() => getNextPage(baseUrl, ++pageNum))
}

getNextPage(baseUrl, 1)
  .then(() => {
    console.log('done')
  })
  .catch(err => console.error(err))