Just a twitch username checker in nodejs.

checker.js

#!/usr/bin/env node

const ArgumentParser = require("argparse").ArgumentParser;
const fs             = require("fs");
const colors         = require("colors");
const request        = require("request");

const parser = new ArgumentParser({
  version: "0.0.1",
  addHelp: true,
  description: "Print if a username in <file> is not registered on twitch.tv"
});
parser.addArgument("file", { help: "File which contains a list of usernames" });
parser.addArgument("--verbose", { help: "Enables verbose mode",
                                  required: false,
                                  defaultValue: false });

const args = parser.parseArgs();

if (!fs.existsSync(args.file)) {
  console.error(`${"Error".red}: file '${args.file}' does not exists.`.bold);
  process.exit(1);
}

const users = fs.readFileSync(args.file).toString().replace(/\r/g, "")
                .split("\n");

if (args.verbose)
  console.log(`Successfully loaded ${users.length} users: ${users.join(", ")}.`);

const clientId = "Your twitch client id key";
const opts = {
    "url": "",
    headers: {
      "Accept": "application/vnd.twitchtv.v5+json",
      "Client-ID": clientId
    }
};

for (let user of users) {
  opts.url = `https://api.twitch.tv/kraken/users?login=${user}`;

  request(opts, (err, res, body) => {
    body = JSON.parse(body);
    if (body["_total"] == 0)
      console.log(`Username ${colors.green(user).bold} is available.`);
    else if (args.verbose)
      console.log(`Username ${colors.red(user).bold} is unavailable.`);
  });
}

package.json

{
  "name": "twitch-checker",
  "version": "0.0.1",
  "description": "A simple twitch account checker.",
  "main": "checker.js",
  "scripts": {
    "test": "node checker.js"
  },
  "author": "lodi-g",
  "license": "MIT",
  "dependencies": {
    "argparse": "^1.0.9",
    "colors": "^1.1.2",
    "request": "^2.79.0"
  }
}