add LoggerBehavior

Apps/Website/appsettings.Development.json

@@ -4,7 +4,8 @@
       "Default": "Information",
       "Microsoft": "Warning",
       "Microsoft.Hosting.Lifetime": "Information",
-      "Microsoft.EntityFrameworkCore": "Information"
+      "Microsoft.EntityFrameworkCore": "Information",
+      "HN.Application": "Information"
     }
   }
 }

Infrastructure/Behaviors/LoggerBehavior.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using MediatR;
+using Microsoft.Extensions.Logging;
+
+namespace HN.Infrastructure.Behaviors
+{
+  public sealed class LoggerBehavior<TRequest, TResponse> : IPipelineBehavior<TRequest, TResponse>
+  {
+    private readonly ILoggerFactory _factory;
+
+    public LoggerBehavior(ILoggerFactory factory)
+    {
+      _factory = factory;
+    }
+
+    public async Task<TResponse> Handle(TRequest request, CancellationToken cancellationToken, RequestHandlerDelegate<TResponse> next)
+    {
+      var logger = _factory.CreateLogger(request.GetType());
+
+      logger.LogInformation("Processing request {0} at {1}", request, DateTime.Now);
+
+      var response = await next();
+
+      logger.LogInformation("Processed request {0} at {1}", request, DateTime.Now);
+
+      return response;
+    }
+  }
+}

Infrastructure/ServiceCollectionExtensions.cs

@@ -33,6 +33,7 @@ namespace HN.Infrastructure
       services.AddScoped<ILinkRepository, LinkRepository>();
       services.AddScoped<ICommentRepository, CommentRepository>();
       services.AddScoped(typeof(IPipelineBehavior<,>), typeof(UnitOfWorkBehavior<,>));
+      services.AddSingleton(typeof(IPipelineBehavior<,>), typeof(LoggerBehavior<,>));
       services.AddMediatR(typeof(HN.Application.IHNContext));
 
       return new HNServicesBuilder(services);