Get npm download count by period

get-npm-download-count.js

const path = require('path')
const fetch = require('node-fetch')
const flatcache = require('flat-cache')

/* Download API
period: Joi.string().regex(/(\d{4}-\d{2}-\d{2}(:\d{4}-\d{2}-\d{2})?|[\w-]+)/).required(),

Package "package-name", last week:
  /downloads/point/last-week/package-name
Package "package-name", given 7-day period:
  /downloads/point/2014-02-01:2014-02-08/package-name
Package "package-name", last 30 days:
  /downloads/point/last-month/package-name
Package "package-name", specific month:
  /downloads/point/2014-01-01:2014-01-31/package-name
*/

const lastYear = `${getDateRange(-365)}:${getDateRange()}`
const TIMEFRAMES = {
  'last-day': 'last-day',
  '1d': 'last-day',
  'last-week': 'last-week',
  '1w': 'last-week',
  'last-month': 'last-month',
  '1m': 'last-month',
  'last-year': lastYear,
  '1y': lastYear,
}

async function getStats(opts) {
  if (!opts.pkg) {
    throw new Error('No pkg name specified')
  }
  if (!opts.timeframe) {
    throw new Error('No timeframe specified')
  }
  let cache = flatcache.load('npm-downloads', path.resolve('./cache'))
  let key = getCacheKey()
  let cachedData = cache.getKey(key)
  if (cachedData) {
    console.log(`Returning cached results for ${opts.timeframe}...`)
    return cachedData
  }
  const range = TIMEFRAMES[opts.timeframe] || opts.timeframe
  console.log(`Fetching new npm download count for ${opts.timeframe}...`)
  try {
    // let newData = await fetch("https://api.npmjs.org/downloads/point/last-month/${pkg}")
    let newData = await fetch(`https://api.npmjs.org/downloads/point/${range}/${opts.pkg}`)
      .then(res => res.json())
      .then(json => {
        return {
          downloads: json.downloads
        }
      })

    cache.setKey(key, newData)
    cache.save()
    return newData
  } catch (e) {
    console.log('Failed, returning 0')
    return {
      downloads: 0
    }
  }
}

function getCacheKey() {
  let date = new Date()
  return `${date.getUTCFullYear()}-${date.getUTCMonth() + 1}-${date.getUTCDate()}`
}

function pad(num) {
  return `${num < 10 ? '0' : ''}${num}`
}
function getDateRange(daysOffset) {
  let date = new Date()
  if (daysOffset) {
    date.setTime(date.getTime() + daysOffset * 1000 * 60 * 60 * 24)
  }
  return `${date.getUTCFullYear()}-${pad(date.getUTCMonth() + 1)}-${pad(date.getUTCDate())}`
}

getStats({
  pkg: 'analytics',
  timeframe: 'last-year',
}).then((data) => {
  console.log('d', data)
}).catch((e) => {
  console.log('e', e)
})