What is forkjoin in rxjs?

In RxJS, the forkJoin operator is used to combine multiple Observables into a single Observable, where the combined observable emits an array of values representing the latest value from each of the original observables.

The forkJoin operator works by subscribing to all input observables, and it only emits the values from the observables when all of them have completed. This is useful in scenarios where you want to wait for multiple independent operations to complete before proceeding to the next step.

Here is an example usage of forkJoin:

import { forkJoin, of } from 'rxjs';

const obs1 = of(1, 2, 3);
const obs2 = of(4, 5, 6);

const combinedObs = forkJoin(obs1, obs2);
combinedObs.subscribe(values => console.log(values));
// Output: [3, 6]

In this example, obs1 and obs2 are two independent observables. The forkJoin operator combines these observables into a single combinedObs observable, which emits an array of values [3, 6] representing the latest values from obs1 and obs2.