zapier_code_use_basic_authentication_with_fetch.js

var username = '';
var password = '';

var encoded_credentials = new Buffer(username + ':' + password).toString('base64');

fetch('https://example.com', { method: 'POST', headers: {'Authorization': 'Basic ' + encoded_credentials} })
	.then(function(res) {
		return res.json();
	})
	.then(function(body) {
		var output = {content: body};
		callback(null, output);
	})
	.catch(callback);