public static void ConfigureExceptionHandler()

in src/Web/Middleware/ExceptionHandlingMiddleware.cs [18:63]
42 lines of code
2 McCabe index (conditional complexity)

        public static void ConfigureExceptionHandler(this IApplicationBuilder app)
        {
            app.UseExceptionHandler(errorApp =>
            {
                errorApp.Run(async context =>
                {
                    context.Response.StatusCode = 500;
                    context.Response.ContentType = "text/html";

                    var sb = new StringBuilder();
                    sb.AppendLine("<html lang='en'><body>");
                    sb.AppendLine("<h2><a href='/'>&larr; Back home</a></h2>");

                    var exceptionHandlerPathFeature = context.Features.Get<IExceptionHandlerPathFeature>();
                    if (exceptionHandlerPathFeature?.Error is FraudProtectionApiException e)
                    {
                        sb.AppendLine("<h2>Fraud Protection API error!</h2>");
                        using (e.Response)
                        {
                            sb.AppendLine("<h3>Request</h3>");
                            sb.AppendLine("<pre>");
                            sb.AppendLine(SanitizeAuthHeader(e.Response.RequestMessage.ToString()));
                            sb.AppendLine(await ReadContent(e.Response.RequestMessage.Content));
                            sb.AppendLine("</pre>");
                            sb.AppendLine("<h3>Response</h3>");
                            sb.AppendLine("<pre>");
                            sb.AppendLine(e.Response.ToString());
                            sb.AppendLine(await ReadContent(e.Response.Content));
                            sb.AppendLine("</pre>");
                        }
                    }
                    else
                    {
                        sb.AppendLine("<h2>Non Fraud Protection API error!</h2>");
                        sb.AppendLine("<a href='https://github.com/microsoft/Dynamics-365-Fraud-Protection-Samples/issues/new/choose' target='_blank'>Consider reporting this sample app bug</a><br />");
                        sb.AppendLine("<pre>");
                        sb.AppendLine(exceptionHandlerPathFeature?.Error.ToString());
                        sb.AppendLine("</pre>");
                    }

                    sb.AppendLine("</body></html>");

                    await context.Response.WriteAsync(sb.ToString());
                });
            });
        }