Declined
Last Updated: 04 Jul 2022 12:11 by ADMIN
StillLearnin
Created on: 21 Jun 2022 21:35
Type: Bug Report
1
HTML5 report viewer cancel button does not cancel report generation on the server

Clicking the cancel button on the HTML5 report viewer show "Report processing was canceled" in the UI but the report is still being generated and rendered on the server.

In this old thread it is stated that it isn't possible to cancel the report generation on the server. Is that still the case?

3 comments
ADMIN
Dimitar
Posted on: 04 Jul 2022 12:11

Hello,

Our apologies if the question was misunderstood.

The CancellationToken is being sent automatically by the report viewer when the 'Cancel' button on the report viewer toolbar is clicked, no additional C# code is required for this functionality to work.

The case is currently being discussed in a separate support ticket. If a problem with the HTML5 Report Viewer cancellation of the report rendering is discovered, this item will be updated to reflect it.

Regards,
Dimitar
Progress Telerik

Brand new Telerik Reporting course in Virtual Classroom - the free self-paced technical training that gets you up to speed with Telerik and Kendo UI products. Check it out at https://learn.telerik.com/.
StillLearnin
Posted on: 28 Jun 2022 13:41

My apologies for not making myself clear enough.

Clicking the cancel button causes the UI to display "Report processing was canceled" and the report never displays in the viewer. This is expected and correct behavior.

However, if you watch the report servers' resource consumption (RAM, CPU, etc.) it is obvious that the server is still rendering the report as the resource consumption continues to grow until the report has finished rendering.

I know how to use task cancellation tokens in other C# coding that I do but I couldn't find documentation on how to use the Cancellation Token when using your HTML5 report viewer and Reporting REST service. Could you point me to the documentation please?

ADMIN
Todor
Posted on: 28 Jun 2022 10:34

Hi Melvin,

I confirm that you may cancel the report rendering by passing Cancellation Token to the RenerReport and PrintReport methods of the ReportProcessor. We introduced this feature with R2 2020 (14.1.20.513) - Allow the ReportProcessor to cancel the current report rendering. The cancellation is available also to the viewers with our latest versions.

Please, note that the cancellation doesn't happen immediately. If report generation is fast enough, the report may be already rendered before the cancellation token is passed to the ReportProcessor as the request for cancellation is sent through the Reporting REST Service.

I tested with our ReportBook online demo and managed to cancel the rendering. The first report was already rendered, but the rendering of the rest of the reports in the book was effective. I tried also with our examples and managed to cancel the report rendering in debug mode.

For the above reasons, I have marked this bug report as declined.

Regards,
Todor
Progress Telerik

Brand new Telerik Reporting course in Virtual Classroom - the free self-paced technical training that gets you up to speed with Telerik and Kendo UI products. Check it out at https://learn.telerik.com/.