npm-parse.js

#!/usr/bin/env node
const https = require('node:https')
const es = require('event-stream')
const JSONStream = require('JSONStream')

const main = async () => {
  const r = []
  for (let i = 0; i < 10; i++) {
    r.push(new Promise((resolve, reject) => {
      if (process.argv[2] === 'stream') {
        const req = https.request(new URL('https://registry.npmjs.org/npm'), function (res) {
          res
          .pipe(JSONStream.parse('dist-tags'))
          .pipe(es.mapSync(function (data) {
            console.log(data.latest)
            resolve(data)
            res.destroy()
          }))
        })
        req.on('error', (err) => {
          reject(err)
        })
        req.end()
      } else {
        let raw = ''
        const req = https.request(new URL('https://registry.npmjs.org/npm'), function (res) {
          res.on('data', d => {
            raw = raw + d.toString('utf8')
          })
          res.on('end', () => {
            const p = JSON.parse(raw)
            console.log(p['dist-tags'].latest)
            resolve(p['dist-tags'])
          })
        })
        req.on('error', (err) => {
          reject(err)
        })
        req.end()
      }
    }))
  }
  await Promise.all(r)
}

main()
  .catch(err => {
  console.error(err)
  process.exit(1)
})