RxJs: redux-observable and buffer debounce

debounce.js

export const startWsEpic = action$ => action$.pipe(
  ofType(START_WS),
  mergeMap(action => {
    const source$ = ws(action.payload).pipe(share())

    return source$.pipe(
      takeUntil(action$.ofType(STOP_WS)),
      buffer(source$.pipe(debounceTime(100))),
      map(data => updateData(data)),
      catchError(() => of(updateDataError()))
    )
  })
)