Using Async, Await, Plus a Slight Delay

Today’s problem dealt with how we view our invoices online.  We use an app on the iSeries that creates a PDF and delivers it to a set destination.  That destination, in our case is a regular windows server, the files landing in a small site:   pdf.mycompany.com.

My initial approach was simple, use the PHP API I have sitting on the iSeries to make a call to the program – passing it the parameters for that specific invoice, await response (which gave me the new created filename) and then redirect to that URL.  The method looks something like this:

[HttpGet]
public async Task<ActionResult> GetInvoiceAsync(int invoice)
{
    GetInvoice getInvoice = new GetInvoice();
    var client = new HttpClient();

    string fileName = await getInvoice.LoadPDF(invoice);

    string url = "http://pdf.mycompany.com/";
    url += fileName + ".pdf";

    return Redirect(url);
}

 

This worked great… 90% of the time, but the other 10% of the time, I clicked too quickly on an invoice and got forwarded to a 404.…