In my Ionic web app,

> 
> For browser
> 
> 
> 

I want to implement a cancel download feature and currently, users can download multiple files at the same time so I want to cancel specific download HTTP request.

This is what I currently have.

```
@Effect()
public fileDownloadAction$: Observable<Action> = this.action$
    .ofType(FileDownloadActionTypes.FILE_DOWNLOAD_REQUESTED)
    .map(this.toPayload)
    .mergeMap(payload => (this.downloadService.downloadFile(payload))
        .concatMap((res: any) => {                       
            return Observable.from([
                new FileDownloadCompleted(downloadSuccess)
            ]);
        })
    )

```

But I don't have a clue how to do this inside an effect. Any suggestions?
Thanks in advance :-)