title: Enable Synchronous IO in Azure Function
body: <p>I am building a HTTPTriggered Azure Function, targeting netcoreapp3.0, that is running a GraphQL .NET server. GraphQL .NET requires that <code>AllowSynchronousIO</code> is set to <code>true</code>, but I can't figure out how to do that for a Azure Function. I have tried implementing my own <code>Startup</code> class that extends <code>FunctionsStartup</code> and added the below code in the <code>Configure</code> method with no luck.</p>
  
  <pre><code>builder.Services
      .AddOptions&lt;KestrelServerOptions&gt;()
      .Configure&lt;IConfiguration&gt;((settings, configuration) =&gt;
      {
          settings.AllowSynchronousIO = true;
          configuration.Bind(settings);
      });
  </code></pre>
  
  <p>The error message I get is:</p>
  
  <blockquote>
    <p>An unhandled host error has occurred.</p>
    
    <p>Microsoft.AspNetCore.Server.Kestrel.Core: Synchronous operations are
    disallowed. Call WriteAsync or set AllowSynchronousIO to true instead.</p>
  </blockquote>
  
  <p>Any help would be greatly appreciated!</p>