From a93a680e03b756e5334e386c44a66d47745ab33f Mon Sep 17 00:00:00 2001
From: Cyberboss <Cyberboss@users.noreply.github.com>
Date: Mon, 27 Aug 2018 11:48:32 -0400
Subject: [PATCH] Supress errors from cancelled requests. Log them as debug

---
 .../Controllers/ApiController.cs               |  9 ++++++++-
 src/Tgstation.Server.Host/Core/Application.cs  |  2 ++
 .../Core/ApplicationBuilderExtensions.cs       | 18 ++++++++++++++++++
 3 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/src/Tgstation.Server.Host/Controllers/ApiController.cs b/src/Tgstation.Server.Host/Controllers/ApiController.cs
index 9d89a62b52..16fa1704dd 100644
--- a/src/Tgstation.Server.Host/Controllers/ApiController.cs
+++ b/src/Tgstation.Server.Host/Controllers/ApiController.cs
@@ -203,7 +203,14 @@ namespace Tgstation.Server.Host.Controllers
 
 			Logger.LogDebug("Request made by User ID {0}. Api version: {1}. User-Agent: {2}. Type: {3}. Route {4}{5} to Instance {6}", AuthenticationContext?.User.Id.ToString(CultureInfo.InvariantCulture), ApiHeaders.ApiVersion, ApiHeaders.UserAgent, Request.Method, Request.Path, Request.QueryString, ApiHeaders.InstanceId);
 
-			await base.OnActionExecutionAsync(context, next).ConfigureAwait(false);
+			try
+			{
+				await base.OnActionExecutionAsync(context, next).ConfigureAwait(false);
+			}
+			catch (OperationCanceledException e)
+			{
+				Logger.LogDebug("Request cancelled! Exception: {0}", e);
+			}
 		}
 	}
 }
diff --git a/src/Tgstation.Server.Host/Core/Application.cs b/src/Tgstation.Server.Host/Core/Application.cs
index 743ed7b490..556c2d1fbe 100644
--- a/src/Tgstation.Server.Host/Core/Application.cs
+++ b/src/Tgstation.Server.Host/Core/Application.cs
@@ -244,6 +244,8 @@ namespace Tgstation.Server.Host.Core
 
 			applicationBuilder.UseDbConflictHandling();
 
+			applicationBuilder.UseCancelledRequestSuppression();
+
 			applicationBuilder.UseMvc();
 		}
 
diff --git a/src/Tgstation.Server.Host/Core/ApplicationBuilderExtensions.cs b/src/Tgstation.Server.Host/Core/ApplicationBuilderExtensions.cs
index b86e780895..becd3e5ad6 100644
--- a/src/Tgstation.Server.Host/Core/ApplicationBuilderExtensions.cs
+++ b/src/Tgstation.Server.Host/Core/ApplicationBuilderExtensions.cs
@@ -35,5 +35,23 @@ namespace Tgstation.Server.Host.Core
 				}
 			});
 		}
+
+		/// <summary>
+		/// Suppress TaskCanceledException warnings when a user aborts a request
+		/// </summary>
+		/// <param name="applicationBuilder">The <see cref="IApplicationBuilder"/> to configure</param>
+		public static void UseCancelledRequestSuppression(this IApplicationBuilder applicationBuilder)
+		{
+			if (applicationBuilder == null)
+				throw new ArgumentNullException(nameof(applicationBuilder));
+			applicationBuilder.Use(async (context, next) =>
+			{
+				try
+				{
+					await next().ConfigureAwait(false);
+				}
+				catch (OperationCanceledException) { }
+			});
+		}
 	}
 }