async/await

Error handling is a crucial aspect of any Node.js application development. Failing to handle errors properly can lead to crashes, bugs, and security vulnerabilities. In this blog post, we will explore various techniques and best practices for effective error handling in Node.js. Creating Exceptions In Node.js, errors are handled through exceptions. To throw an exception, you can use the throw keyword followed by a value. In client-side code, the value can be any JavaScript value, such as a string, number, or object....

Promises have greatly improved JavaScript in recent years, allowing us to handle asynchronous operations more efficiently. When working with functions that return promises, it’s important to know how to handle promise rejections. In this blog post, we’ll explore the best practices for handling promise rejections effectively. Let’s start with a simple example using the Fetch API: fetch('/data.json') .then(response => { console.log(response.status) }) But what if an error occurs during the fetch() call?...

If you are using Babel in your project and you encounter the regeneratorRuntime is not defined error after adding an async function or any recent JavaScript feature, don’t worry. This issue can be resolved by loading the regenerator-runtime runtime in addition to the polyfill generated by Babel, which is used by Parcel. Here’s a solution you can try: add the following line at the top of your main JavaScript file:...

Learn how to retrieve the result of an asynchronous function, whether it is promise-based or callback-based, using JavaScript. Imagine you encounter this scenario: you need to return the result of an asynchronous call from the original function. Here is a simplified example: const mainFunction = () => { const result = asynchronousFunction(); return result; } However, asynchronousFunction() performs an asynchronous operation, such as a fetch() call, and cannot directly return the result value....

In the world of Node.js, many APIs and libraries were built before the introduction of promises. As a result, they rely on a callback-based solution. However, working with nested callbacks can lead to a complex and messy code structure commonly known as “callback hell.” Thankfully, there is a solution: the use of promises and the await keyword. To remove callbacks and make use of promises, Node.js provides a useful utility called promisify from the util module....

Node.js built-in modules are well-known for not being promise-based. This was because these modules were created before promises became popular. Although the promisify function has been available for some time, Node.js introduced a new promise-based API starting from version 10. Currently, this new API is only available for the fs built-in module, and it remains uncertain whether it will be implemented for other native modules in the future. To utilize this new API, follow these steps:...

In JavaScript, there are situations where we need to wait for multiple promises to resolve before continuing the execution of our code. Instead of waiting for one promise to resolve and then starting the next one, it would be more efficient to start all the promises simultaneously and wait for all of them to finish. In this blog post, we will discuss how to achieve this using the await keyword and the Promise....

The Event Loop is a fundamental concept to understand in Node.js. It explains how Node can be asynchronous and have non-blocking I/O, which is what makes it so successful. Node.js code runs on a single thread, meaning that only one thing can happen at a time. While this may seem like a limitation, it simplifies programming by eliminating the need to worry about concurrency issues. However, it is important to be mindful of how you write your code to avoid blocking the thread....