password-blacklist/index.js

Check passwords against a blacklist

const readline = require('readline')
const path = require('path')
const zlib = require('zlib')
const fs = require('fs')

const passwordFilename = path.resolve(__dirname, './data/passwords.txt.gz')

module.exports = (password) => new Promise((resolve, reject) => {
  const file = fs.createReadStream(passwordFilename).on('error', onError)
  const gunzip = zlib.createGunzip().on('error', onError)
  const lines = readline.createInterface({
    input: file.pipe(gunzip)
  }).on('line', (input) => {
    if (input === password || input.trim().toLowerCase() === password.trim().toLowerCase()) {
      resolve(true)
      cleanup()
    }
  }).on('close', () => resolve(false))
    .on('error', onError)

  function onError (err) {
    reject(err)
    cleanup()
  }

  function cleanup () {
    file.close()
    // crashes for some reason
    // gunzip.close()
    lines.close()
  }
})