Nothing happens on datasource after error is caught

[Vedad]

Hi and happy new year!

 

I have strange behaviour on my gantt datasource occurring when read request returns error 500. (i am stuck with specific endpoint which returns 500 instead of 404 when requested item is not found).

- I instantiate gantt widget and set all required options and datasource(s).
- Under read request specific project id is passed to the server. 
- Server responds with 500 and I catch it with error: function (e) {
return myErrorHandler(e, $scope); }, //Handler basically reads error and displays adequate message
- Gantt is rendered but it is empty as expected.

- I use my project selector and chose another ID that 100% exists. 
- I reset my datasource using new ID and use gantt.setDataSource to update gantt.
- Data is read from the server, no error.
- Schema: Parse is completed successfully with data. But no dataBound or anything else happens after and widget gets stuck on loading spinning wheel and doesn't populate data.

If first step is performed with correct ID (no error) widget is rendered correctly and then second step (opening other project) is working perfectly fine.

I tried with sync, refresh, read afterwards on the widget, but no success. I tried commenting out error handling implemented, but also no success.

I suspect error caught does something specific to the datasource and/or widget, but I cannot figured it out.

Any help/suggestion is more than welcome.

Thank you and regards,

Vedad

[Petar]

Hi Vedad,

Based only on the reproduction steps I cannot say what might be triggering the reported behavior. To be able to help you I will need a runnable project in which I can reproduce the case. Can you send me a runnable project in which I can test the reported issue? 

Are there any other errors in the browser's console when you get the 500 server error?

If you don't want to expose your project publicly, you can submit a new Support ticket with your project and tell me the number of this ticket, so I can further investigate the issue. 

Looking forward to your reply. 

Regards,
Petar
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[Vedad]

Hi Petar, 

Thank you for your response. Problem with providing you with the code is that I have no way of simulating backend endpoint outside of the system, and that code I cannot provide in any way. 

I was hoping you might have idea what can happen within datasource itself so it simply stops working. I have feeling that widget disconnects from the datasource in case of the error. I tracked state of data within datasource in step after error, and datasource contains data, but for some reason widget is stuck in non-finished cycle from before. While waiting your answer I tried using $ajax approach and using error handling there, but result is the same.

I will try to step into lib and debug it there, so if I come to some point where I suspect some component there I will write.

Meanwhile, if you could think of any other thing to look at please let me know.

Thanks

Vedad

[Petar]

Hi Vedad,

The issue could be triggered because of the result of the used parse function. Can you send me the definition of the parse function and what do you pass to the setDataSource method?

Looking forward to your reply.

Regards,
Petar
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[Vedad]

Hi Petar, 

sorry for waiting for the reply, but I was away. I will try to extract necessary info and post it here.

Thanks.

[Petar]

Hi Vedad,

OK. No worries. Take your time and send the previously discussed code so I could further investigate what could be the reason for the issue. 

Regards,
Petar
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[Kyle]

Has there been any update on this?  I'm getting the same type of behavior with a TreeView.

[Petar]

Hi Kyle,

I can see that there is a support ticket communication about the issue with the TreeView and its DataSource. I am writing here to update the community about the status of the issue. 

The reported behavior with the TreeView's DataSource has been logged as a bug. Its public thread can be followed on this link: https://feedback.telerik.com/kendo-jquery-ui/1467876-treeview-not-refreshed-on-successful-read-request-after-a-previously-failed-request from our feedback portal.

The linked item can be followed. Once there is a change in the item's status, the people who follow it will be notified about the status update.

Regards,
Petar
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