Adds logging for cancelled requests and DbUpdateExceptions

src/Tgstation.Server.Host/Core/ApplicationBuilderExtensions.cs

@@ -1,6 +1,9 @@
 using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
 using System;
 using System.Globalization;
 using Tgstation.Server.Api.Models;
@@ -12,6 +15,13 @@ namespace Tgstation.Server.Host.Core
 	/// </summary>
 	static class ApplicationBuilderExtensions
 	{
+		/// <summary>
+		/// Gets a <see cref="ILogger"/> from a given <paramref name="httpContext"/>
+		/// </summary>
+		/// <param name="httpContext">The <see cref="HttpContext"/> to get the <see cref="ILogger"/> from</param>
+		/// <returns>A new <see cref="ILogger"/></returns>
+		static ILogger GetLogger(HttpContext httpContext) => httpContext.RequestServices.GetRequiredService<ILogger<Application>>();
+
 		/// <summary>
 		/// Return a <see cref="ConflictObjectResult"/> for <see cref="DbUpdateException"/>s
 		/// </summary>
@@ -22,12 +32,14 @@ namespace Tgstation.Server.Host.Core
 				throw new ArgumentNullException(nameof(applicationBuilder));
 			applicationBuilder.Use(async (context, next) =>
 			{
+				var logger = GetLogger(context);
 				try
 				{
 					await next().ConfigureAwait(false);
 				}
 				catch (DbUpdateException e)
 				{
+					logger.LogDebug("Database conflict: {0}", e.Message);
 					await new ConflictObjectResult(new ErrorMessage { Message = String.Format(CultureInfo.InvariantCulture, "A database conflict has occurred: {0}", (e.InnerException ?? e).Message) }).ExecuteResultAsync(new ActionContext
 					{
 						HttpContext = context
@@ -46,11 +58,15 @@ namespace Tgstation.Server.Host.Core
 				throw new ArgumentNullException(nameof(applicationBuilder));
 			applicationBuilder.Use(async (context, next) =>
 			{
+				var logger = GetLogger(context);
 				try
 				{
 					await next().ConfigureAwait(false);
 				}
-				catch (OperationCanceledException) { }
+				catch (OperationCanceledException)
+				{
+					logger.LogDebug("Request cancelled!");
+				}
 			});
 		}
 	}