Apresentação Node.js

asyncAwait.js

async function sendAsync(userId) {
  let user = await getUser(userId);
  let profile = await getProfile(user);
  let account = await getAccount(profile);
  let report = await getReport(account);
  
  let send = sendStatistic(report);
  
  console.log(send);
}

callback.js

getUser(userId, (error, user) => {
	getProfile(user, (error, profile) => {
		getAccount(profile, (error, account) => {
			getReport(account, (error, report) => {
				sendStatistics(report, (error) => {
					...
				});
			});
		});
	});
});

promise.js

getUser(userId)
	.then(getProfile)
	.then(getAccount)
	.then(getReport)
	.then(sendStatistics)
	.then((success) => {
		console.log(success);
	})
	.catch((error) => {
		console.log(error);
	});