.Net Core api long running request

I have a web app calling a .Net Core API for generating PDF documents. I'm doing a bunch of HTML to pdf conversion so it takes a while to complete 200 pages document. I have it working in my local but not my AppService. At first, I was getting "The specified CGI application encountered an error and the server terminated the process." if I went over 100 pages (small page sets work).

The code calling my api:

var httpClient = new HttpClient(); HttpContent content = new StringContent(JsonConvert.SerializeObject(pdfRecipeDto), Encoding.UTF8, "application/json"); httpClient.Timeout = System.TimeSpan.FromMinutes(30); var pdfFileUrl = httpClient.PostAsync("http://yada-yada.azurewebsites.net/api/pdf/Generate", content) .GetAwaiter() .GetResult() .Content.ReadAsStringAsync().Result; // yes i know this is gross 

I found this post and others that said simular. tried the first answer but after manually modifying my web.config in Kudu (bc i don't know how to set it in my project)

<?xml version="1.0" encoding="utf-8"?> <configuration> <system.webServer> <handlers> <add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModule" resourceType="Unspecified"/> </handlers> <aspNetCore requestTimeout="00:20:00" processPath="%LAUNCHER_PATH%" arguments="%LAUNCHER_ARGS%" stdoutLogEnabled="false" stdoutLogFile=".\logs\stdout" forwardWindowsAuthToken="false"/> </system.webServer> </configuration> 

the requestTimeout="00:20:00" being the important part.

But i get a "500 - The request timed out. The web server failed to respond within the specified time.".

i also tried the adding .UseKestrel(...) to my program.cs

public static IWebHost BuildWebHost(string[] args) => WebHost.CreateDefaultBuilder(args) .UseApplicationInsights() .UseStartup<Startup>() .UseKestrel(o => { o.Limits.KeepAliveTimeout = TimeSpan.FromMinutes(30); }) .Build();; 

But that seemed to do nothing.