PDFViewer throws js exceptions and becomes unusable after a failed attempt to load a file

[IvanDanchev]

Bug report

Reproduction of the problem

Dojo:
https://dojo.telerik.com/amSOzNjP

Click the load file button. The standard error message is displayed. Close the info box.
Click the load file button again. An error is thrown in the console and nothing happens. You can't even open a file using the standard open file command.

Using an MVC/Core project:

1. Initialize a PDFViewer and add a button that calls a controller action on click.

<div id="pdfViewer">
</div>

<script type="text/javascript">
    $("#pdfViewer").kendoPDFViewer({
        pdfjsProcessing: {
            file: ""
        }
    });

    function loadFile() {
        $("#pdfViewer").data("kendoPDFViewer").fromFile("@Url.Action("GetPDF", "Home")");
    }
</script>

2. Implement an action that returns a .pdf file or occasionally returns HttpNotFoundResult:

public ActionResult GetPDF()
{

    var name = "sample.pdf";
    string path = Server.MapPath("/Content/pdf/sample.pdf");

    //generate a random boolean:
    Random rng = new Random();
    bool randomBool = rng.Next(0, 2) > 0;
            
    if (randomBool)
    {
        byte[] fileBytes = System.IO.File.ReadAllBytes(path);
        return File(fileBytes, System.Net.Mime.MediaTypeNames.Application.Octet, name);
    }
    else
    {
        return new HttpNotFoundResult("File not found.");
    }
}

Current behavior

In the case where the request returns HttpNotFoundResult, a number of js errors are thrown:

util.js:417 Uncaught (in promise)

The user loses the ability to load a file, because subsequent attempts to load a file by clicking the button result in another js exception:

api.js:1114 Uncaught TypeError: Cannot read properties of null (reading 'sendWithStream')

Expected/desired behavior

The component should show a message that a file is not found, without throwing js exceptions and should not become unusable after a failed attempt to load a file.

Environment

• Kendo UI version: 2024.1.319
• jQuery version: x.y
• Browser: [all]

[gdenchevprog]

No longer reproducible after the integration of the common engine.