What is promise chaining in Node.js?

What is promise chaining in Node.js?

Promise chaining is a technique in JavaScript where multiple promises are linked together, allowing for sequential asynchronous operations.

Can you give me an example of promise chaining?

Sure! Here's a simple example:

function fetchData() {
    return new Promise((resolve) => {
        setTimeout(() => resolve('Data fetched!'), 1000);
    });
}

function processData(data) {
    return new Promise((resolve) => {
        setTimeout(() => resolve(data + ' Processed!'), 1000);
    });
}

fetchData()
    .then(processData)
    .then(result => console.log(result)); // Outputs: 'Data fetched! Processed!'

What happens if one of the promises fails?

If a promise in the chain fails, the subsequent promises will be skipped, and the error can be caught using a .catch() method at the end of the chain.