freemail-cli

#!/usr/bin/env node
const parser     = require('meow');
const fs         = require('fs');
const path       = require('path');
const split      = require('split');
const disposable = load('freemail/data/disposable.txt');
const free       = extend(load('freemail/data/free.txt'), disposable);

const cli = parser(`
  Usage
    $ freemail-cli [options] <file>

  Matches free emails, including disposable, by default

  Options
    -d, --disposable  Only match disposable emails
    -i, --inverse     Print emails that don't match

  Examples
    $ freemail-cli ./path/to/file
    $ cat ./path/to/file | freemail-cli
`, {
  boolean: ['d', 'i'],
  alias: {
    d: 'disposable',
    i: 'inverse'
  }
});

const file = cli.input[0];
if (file && !isFile(file)) {
  console.error('Invalid file path');
  process.exit(1);
}

const readStream = file ? fs.createReadStream(file) : process.stdin;
readStream
  .pipe(split())
  .on('data', (line) => {
    if (cli.flags.inverse ^ match(line)) console.log(line);
  });

function load(path) {
  return fs.readFileSync(require.resolve(path), 'utf8')
    .split('\n')
    .reduce((res, cur) => {
      res[cur] = true;
      return res;
    }, {});
}

function isFile(path) {
  try {
    const stat = fs.lstatSync(path);
    return !stat.isDirectory();
  } catch (err) {
    return false;
  }
}

function match(line) {
  const split = line.toLowerCase().split('@');
  const domain = split[1] || split[0];

  if (cli.flags.disposable) {
    return !!disposable[domain];
  } else if (cli.flags.free) {
    return !!free[domain];
  } else {
    return !!disposable[domain] || !!free[domain];
  }
}

function extend(a, b) {
  const res = {};
  var key;

  for (key in a) {
    res[key] = a[key];
  }

  for (key in b) {
    res[key] = b[key];
  }

  return res;
}