Last Updated: 14 Sep 2021 09:48 by ADMIN
Created on: 03 Jan 2019 12:20
Category: Grid
Type: Bug Report
Kendo UI Grid binding with SignalR is not working

Hi Kendo Team,

I am working on Kendo UI ASP.NET Core Grid binding with SignalR. But while starting Hub and providing the Promise, I am facing an error "The "promise" option must be a Promise."

I am following this URL for reference: .

Checked on your website as well, but the issue is also coming there. Here is the URL:

In this link, when clicking on "Open In Dojo" button, it opens a new window, then clicks on the Run button. It will generate an error in the console "Uncaught Error: The "promise" option must be a Promise.". 

Please check the attached snapshot.

Please reply asap. Thanks in advance!

1 comment
Alex Hajigeorgieva
Posted on: 10 Jan 2019 12:15
Hi, Bharat,

Thank you very much for bringing this to our attention.

The reason this is happening is because of the referenced SignalR script which is served over HTTP resulting in a mixed content message because of all of the other scripts as well as the Dojo are served over HTTPS. At this point, the script execution stops and an error is thrown.

<script src=""></script>

When that mixed content error is fixed, the connection is made without issues:

Since you are interested in the ASP.NER Core SignalR examples, you should check the demo and the service for Core:

- demo: (this demo will be updated next week as well for the new release)
- service:

I have now logged this in our backlog so that we can update it soon. As a token of appreciation for helping us improve, I have awarded you with some Telerik points:

Kind Regards,
Alex Hajigeorgieva
Progress Telerik
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