I'm trying to get an asynchronous excel export working in one of our grids but I consistently get an **empty xsls** file with **only the collection headers**. 

Data is **properly being rendered in the grid**, with filtering and pagination.

I've tried following the docs over here without success, here's my implementation:

Relevant parts in my `component.ts`:

```
@Input() collection$: Observable<User[]>;

ngOnInit() {
  this.allData = this.allData.bind(this);
}

allData(): Observable<GridDataResult> {
  return this.collection$.pipe(
    map(users => ({ data: users, total: users.length }))
  );
}

```

First thing I tried was to directly return `this.collection$;` but the **behavior was the same**: empty collection inside the excel file thus I tried returning an `Observable<GridDataResult>` instead with no success either. 

Relevant parts in my `component.html`:

```
<kendo-grid
  [kendoGridBinding]="collection$ | async"
  pageSize="10"
  [pageable]="true"
  [filterable]="true"
>
  <ng-template kendoGridToolbarTemplate>
    <button type="button" kendoGridExcelCommand icon="file-excel">
      Export to Excel
    </button>
  </ng-template>

  <!-- columns -->

  <kendo-pager-prev-buttons></kendo-pager-prev-buttons>
  <kendo-pager-info></kendo-pager-info>
  <kendo-pager-next-buttons></kendo-pager-next-buttons>
  <kendo-pager-page-sizes [pageSizes]="[5, 10, 40]"></kendo-pager-page-sizes>
  <kendo-grid-excel
    fileName="Users.xlsx"
    [fetchData]="allData"
  ></kendo-grid-excel>
</kendo-grid>

```

Can anyone shed some light on this? Thanks in advance.