SeunAdelekan

observable
    .pipe(
        map(value => value * 3),
        filter(value => value % 4 === 0)
    ).subscribe(result => console.log(result));

SeunAdelekan

import { Observable } from "rxjs";
import { filter, map } from 'rxjs/operators';

const observable: Observable<number> = new Observable((subscriber) => {
    for (let i = 0; i < 10; i++) {
        subscriber.next(i);
    }
    subscriber.complete();
});

SeunAdelekan

const data = [];

for (let i = 0; i < 10; i++) {
    data.push(i)
}

const values: Array<number> = data
    .map(value => value * 3)
    .filter(value => value % 4 === 0);

SeunAdelekan

read users from DB collection
for each user in users
	check criteria
	if user meets critetia
		perform transformation
		store transformed data in target collection.
	end
end