Angular: combine multiple http requests

Usage : Rxjs combinelatest

import { Observable, combineLatest } from 'rxjs';

return combineLatest(observable1, observable2).

pipe(

    map(([result1,result2]) =>{

          //do your mapping / filtering

          const mappedResult = result2.map(item=>mapper.map(item));

          return mappedResult;

    });

);