Sample Service

sample-service.ts

import {Injectable} from '@angular/core';
import {HttpClient} from "@angular/common/http";
import {forkJoin, Observable} from "rxjs";
import {map} from "rxjs/operators";

@Injectable({
  providedIn: 'root'
})
export class SampleService {

  constructor(private http: HttpClient) {
  }

  save(sample: Sample): Observable<Sample> {
    return this.http.post("http://localhost:3000/samples", sample).pipe(map(this.parser));
  }

  saveAll(samples: Sample[]): Observable<Sample[]> {
    return forkJoin(samples.map(this.save))
  }

  private parser = (value): Sample => new Sample(value.name);
}

export class Sample {
  name: string;

  constructor(name: string) {
    this.name = name;
  }
}