Learning Node.js Development

Promises in Asynchronous Programming

In the previous two chapters, we looked at many important concepts of asynchronous programming in Node. This chapter is about promises. Promises are available in JavaScript since ES6. Although they have been around in third-party libraries for quite some time, they finally made their way into the core JavaScript language, which is great because they're a really fantastic feature.

In this chapter, we'll learn about how promises work, we'll start to understand exactly why they're useful, and why they've even come to exist inside JavaScript. We'll take a look at a library called axios that supports promises. This will let us simplify our code, creating our promise calls easily. We'll actually rebuild an entire ...