In most front-end applications, fetching data from the back-end is a common requirement to provide up-to-date information to the user. Typically, this process is straightforward: know the API endpoint, create a function, call it, process the response, and display it on the page. However, there are scenarios — often rare or specific to certain business needs — where client-server communication must be more sophisticated. In this article, we’ll explore one such case: implementing repetitive API calls (polling) using RxJS.
RxJS Refresher
Before diving into polling, let’s take a moment to refresh our understanding of RxJS. For those new to it, RxJS (Reactive Extensions for JavaScript) is a library that brings reactive programming concepts into the JavaScript ecosystem. It’s particularly useful for managing asynchronous operations, offering powerful tools like Observables, Observers, Subjects, and Operators.