Issue with FastReport OpenSource in .NET Core 9 & Angular

I'm using FastReport OpenSource (2025.1.0) in a .NET Core 9 backend project along with Angular-17 for the frontend. I have installed the necessary dependencies:

• FastReport.OpenSource
• FastReport.OpenSource.Export.PdfSimple
• FastReport.OpenSource.Web

Backend API (Report Generation) I have an API endpoint that generates reports and returns HTML content:

[HttpGet("CustomerListReport")]
public async Task<IActionResult> GenerateCustomerListReport(string reportName)
{
WebReport webReport = new WebReport();
webReport.Width = "100%";

var dataTable = customerServices.CustomerReportData(1); // Fetch report data

string reportPath = Path.Combine("App_Data\\ReportFile", $"{reportName}.frx");
webReport.Report.Load(reportPath);
webReport.Report.RegisterData(dataTable, reportName);
webReport.Report.Prepare();

var htmlContent = webReport.Render().Result.Value;
return Content(htmlContent, "text/html");
}


Frontend Code (Fetching Report) The Angular frontend retrieves the report HTML and embeds it into an iframe:

this.DashboardService.getReportUrl().subscribe((htmlContent: any) => {
const iframe = document.getElementById('reportIframe') as HTMLIFrameElement;
const iframeDoc = iframe.contentDocument || iframe.contentWindow?.document;
if (iframeDoc) {
iframeDoc.open();
setTimeout(() => {
iframeDoc.write(htmlContent);
iframeDoc.close();
}, 100);
}
});

<iframe #report id="reportIframe" height="1000" width="100%"></iframe>


Issue

Backend API runs on: https://localhost:44393/api

Frontend runs on: https://localhost:4200

The report does not render in the iframe.

I noticed that FastReport tries to call an API at https://localhost:4200/fr/preview.Report, but it should be calling https://localhost:44393/fr/preview.Report.

How can I configure FastReport to use the correct backend URL (https://localhost:44393) instead of trying to call the frontend URL (https://localhost:4200)? Any help would be greatly appreciated!

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