const { rxObserver } = require('api/v0.3');
const { timer, NEVER } = require('rxjs');
const { merge, map, tap, take, finalize, retryWhen } = require('rxjs/operators');

const sourceObserver = rxObserver('Source');
const errorsObserver = rxObserver('Errors');
const resultObserver = rxObserver('Result');

timer(10, 10).pipe(
  map(x => {
    const time = Date.now();
    if (time <= 30) {
      throw x;
    }

    return x;
  }),

  tap(sourceObserver),

  retryWhen(errors$ =>
    errors$.pipe(
      take(3),
      // uncomment this to prolong inner observable
      // merge(NEVER),

      // visualization
      tap(errorsObserver),
      finalize(errorsObserver.complete)
    )
  ),

  take(10)
)
.subscribe(resultObserver);