Observables in Angular: what they are and how to use them

Observables are a powerful feature in Angular that allow for handling asynchronous data streams in a declarative manner. They are an important concept to understand when building applications with Angular, as they are used throughout the framework, from handling HTTP requests to creating responsive user interfaces.

What is an Observable?

An observable is a stream of data that can emit multiple values over time. This stream can be observed but also subscribed to. Each value emitted from the stream is referred to as an event, and the observer can trigger an action in response to each event. This allows for a clear separation of concerns between the data source and the component that is consuming the data.

In Angular, the RxJS library provides a wide range of operators that you can use to manipulate observables. For example, filtering, mapping, and combining with the filter, map or combineLatest operators.

How does an Observable work ?

Let’s dig a little deep and see an example of how observables can be used in an Angular application. In the following example, a service makes an HTTP request in order to get a list of users from a remote server. The Angular HttpClient module will make the request, and return the…