Async/Await in Node.js

Async/Await is a modern JavaScript feature that allows for asynchronous programming to be written in a more synchronous manner. It is built on top of Promises and is available in Node.js starting from version 7.6.

2.1 Asynchronous Programming

Asynchronous programming is a method of programming that allows certain operations to run without blocking the execution of other operations.

2.2 Promises

A Promise is an object that represents the eventual completion (or failure) of an asynchronous operation and its resulting value.

2.3 Async/Await Syntax

Async/Await provides a cleaner syntax for working with Promises. The `async` keyword is used to define an asynchronous function, while `await` is used to pause the execution until the Promise is resolved.

3.1 Defining an Async Function

To create an async function, simply prefix the function declaration with the `async` keyword.

async function fetchData() {
    // Asynchronous operation
}

3.2 Using Await

Use the `await` keyword to wait for a Promise to resolve. It can only be used inside async functions.

async function fetchData() {
    const response = await fetch(url);
    const data = await response.json();
    return data;
}

3.3 Error Handling

Use try/catch blocks to handle errors in async functions.

async function fetchData() {
    try {
        const response = await fetch(url);
        if (!response.ok) throw new Error('Network response was not ok');
        const data = await response.json();
        return data;
    } catch (error) {
        console.error('Fetch error:', error);
    }
}

• Always handle errors using try/catch blocks.
• Use descriptive names for async functions.
• Limit the number of `await` statements in a single function to avoid blocking.
• Use `Promise.all` for concurrent async operations.