JS es6 Promises

promise.js

const posts = [
	{ title: 'Post one', body: 'this is post one' },
	{ title: 'Post two', body: 'this is post two' }
];

function createPost(post) {
	return new Promise(function (resolve, reject) {
		setTimeout(function () {
			posts.push(post);
			const error = false;
			if (!error) {
				resolve();
			} else {
				reject('error: something went wrong');
			}
		}, 2000);
	});
}

function getPosts() {
	setTimeout(function () {
		let output = '';
		posts.forEach(function (post) {
			output += `<li>${post.title}</li>`;
		});
		document.body.innerHTML = output;
	}, 1000);
}

createPost({ title: 'post three', body: 'this is post three' })
	.then(getPosts)
	.catch(function (err) {
		console.log(err);
	});