Fetch IdentityServer OAuth token using NodeJS

auth.js

const https = require('https');
const querystring = require('querystring');
const fs = require('fs');

const username = 'user';
const password = 'user123';
const baseAddress = `https://my-auth-server.com`;

const config = {
	'client_id': 'myapi',
	'client_secret': 'secret',
	'grant_type': 'password',
	'scope': 'openid myapiscope',
	'username': username,
	'password': password
}

const data = querystring.stringify(config);
const options = {
	hostname: `my-auth-server.com`,
	port: 443,
	path: '/connect/token',
	method: 'POST',
	headers: {
		'Content-Type': 'application/x-www-form-urlencoded',
		'Content-Length': data.length
	}
}

function requestToken() {
	const req = https.request(options, res => {
		res.on('data', d => {
			console.log(res.statusCode)
			if(res.statusCode == 200) {
				const response = JSON.parse(d);
				console.log('Fetched token successfully');
				console.log(JSON.stringify(response, null, 4));
				save(response.access_token);
			}
		});
	});
	
	req.on('error', error => {
		console.error(error);
	});
	
	req.write(data);
	req.end();
}

function save(token) {
	fs.writeFile("./token.txt", token, function (err) {
		if (err) {
			return console.log(err);
		}
		console.log("The file was saved!");
	});
}

requestToken();

test.js

const authorization = require('./token');

// ...
const headers = {
    'Authorization': authorization,
    'Content-Type': 'application/json'
}
// ...

token.js

const fs = require('fs');
const contents = fs.readFileSync('./token.txt', 'utf8');

module.exports = `Bearer ${contents}`;