#23 Added AbpExceptionHandlingMiddleware

src/Volo.Abp.AspNetCore.Mvc/Microsoft/AspNetCore/Builder/AbpAspNetCoreMvcApplicationBuilderExtensions.cs

@@ -1,4 +1,5 @@
-using Volo.Abp.AspNetCore.Mvc.Uow;
+using Volo.Abp.AspNetCore.Mvc.ExceptionHandling;
+using Volo.Abp.AspNetCore.Mvc.Uow;
 
 namespace Microsoft.AspNetCore.Builder
 {
@@ -6,7 +7,21 @@ namespace Microsoft.AspNetCore.Builder
     {
         public static IApplicationBuilder UseUnitOfWork(this IApplicationBuilder app)
         {
-            return app.UseMiddleware<AbpUnitOfWorkMiddleware>();
+            return app
+                .UseAbpExceptionHandling()
+                .UseMiddleware<AbpUnitOfWorkMiddleware>();
+        }
+
+        public static IApplicationBuilder UseAbpExceptionHandling(this IApplicationBuilder app)
+        {
+            //Prevent multiple add
+            if (app.Properties.ContainsKey("_AbpExceptionHandlingMiddleware_Added")) //TODO: Constant
+            {
+                return app;
+            }
+
+            app.Properties["_AbpExceptionHandlingMiddleware_Added"] = true;
+            return app.UseMiddleware<AbpExceptionHandlingMiddleware>();
         }
     }
 }

src/Volo.Abp.AspNetCore.Mvc/Volo/Abp/AspNetCore/Mvc/AbpActionInfoInHttpContext.cs

@@ -0,0 +1,7 @@
+namespace Volo.Abp.AspNetCore.Mvc
+{
+    public class AbpActionInfoInHttpContext
+    {
+        public bool IsObjectResult { get; set; }
+    }
+}

src/Volo.Abp.AspNetCore.Mvc/Volo/Abp/AspNetCore/Mvc/ExceptionHandling/AbpExceptionFilter.cs

@@ -1,16 +1,12 @@
 using System.Collections.Generic;
-using System.Net;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Abstractions;
 using Microsoft.AspNetCore.Mvc.Filters;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.Abstractions;
 using Microsoft.Extensions.Primitives;
-using Volo.Abp.Authorization;
 using Volo.Abp.DependencyInjection;
-using Volo.Abp.Domain.Entities;
 using Volo.Abp.Http;
-using Volo.Abp.Validation;
 
 namespace Volo.Abp.AspNetCore.Mvc.ExceptionHandling
 {
@@ -21,10 +17,12 @@ namespace Volo.Abp.AspNetCore.Mvc.ExceptionHandling
         //TODO: Use EventBus to trigger error handled event like in previous ABP
 
         private readonly IExceptionToErrorInfoConverter _errorInfoConverter;
+        private readonly HttpExceptionStatusCodeFinder _statusCodeFinder;
 
-        public AbpExceptionFilter(IExceptionToErrorInfoConverter errorInfoConverter)
+        public AbpExceptionFilter(IExceptionToErrorInfoConverter errorInfoConverter, HttpExceptionStatusCodeFinder statusCodeFinder)
         {
             _errorInfoConverter = errorInfoConverter;
+            _statusCodeFinder = statusCodeFinder;
 
             Logger = NullLogger<AbpExceptionFilter>.Instance;
         }
@@ -49,7 +47,7 @@ namespace Volo.Abp.AspNetCore.Mvc.ExceptionHandling
                 return;
             }
 
-            context.HttpContext.Response.StatusCode = GetStatusCode(context);
+            context.HttpContext.Response.StatusCode = _statusCodeFinder.GetStatusCode(context.HttpContext, context.Exception);
             context.HttpContext.Response.Headers.Add(new KeyValuePair<string, StringValues>("_AbpErrorFormat", "true"));
 
             context.Result = new ObjectResult(
@@ -62,27 +60,5 @@ namespace Volo.Abp.AspNetCore.Mvc.ExceptionHandling
 
             context.Exception = null; //Handled!
         }
-
-        private static int GetStatusCode(ExceptionContext context)
-        {
-            if (context.Exception is AbpAuthorizationException)
-            {
-                return context.HttpContext.User.Identity.IsAuthenticated
-                    ? (int)HttpStatusCode.Forbidden
-                    : (int)HttpStatusCode.Unauthorized;
-            }
-
-            if (context.Exception is AbpValidationException)
-            {
-                return (int)HttpStatusCode.BadRequest;
-            }
-
-            if (context.Exception is EntityNotFoundException)
-            {
-                return (int)HttpStatusCode.NotFound;
-            }
-
-            return (int)HttpStatusCode.InternalServerError;
-        }
     }
 }

src/Volo.Abp.AspNetCore.Mvc/Volo/Abp/AspNetCore/Mvc/ExceptionHandling/AbpExceptionHandlingMiddleware.cs

@@ -0,0 +1,92 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Primitives;
+using Microsoft.Net.Http.Headers;
+using Volo.Abp.AspNetCore.Mvc.Uow;
+using Volo.Abp.Http;
+using Volo.Abp.Json;
+
+namespace Volo.Abp.AspNetCore.Mvc.ExceptionHandling
+{
+    public class AbpExceptionHandlingMiddleware
+    {
+        private readonly RequestDelegate _next;
+        private readonly ILogger<AbpUnitOfWorkMiddleware> _logger;
+
+        private readonly Func<object, Task> _clearCacheHeadersDelegate;
+
+        public AbpExceptionHandlingMiddleware(RequestDelegate next, ILogger<AbpUnitOfWorkMiddleware> logger)
+        {
+            _next = next;
+            _logger = logger;
+
+            _clearCacheHeadersDelegate = ClearCacheHeaders;
+        }
+
+        public async Task Invoke(HttpContext httpContext)
+        {
+            try
+            {
+                await _next(httpContext);
+            }
+            catch (Exception ex)
+            {
+                // We can't do anything if the response has already started, just abort.
+                if (httpContext.Response.HasStarted)
+                {
+                    _logger.LogWarning("An exception occured, but response has already started!");
+                    throw;
+                }
+
+                if (httpContext.Items["_AbpActionInfo"] is AbpActionInfoInHttpContext actionInfo)
+                {
+                    if (actionInfo.IsObjectResult)
+                    {
+                        await HandleAndWrapException(httpContext, ex);
+                        return;
+                    }
+                }
+
+                throw;
+            }
+        }
+
+        private async Task HandleAndWrapException(HttpContext httpContext, Exception exception)
+        {
+            _logger.LogException(exception);
+
+            var errorInfoConverter = httpContext.RequestServices.GetRequiredService<IExceptionToErrorInfoConverter>();
+            var statusCodeFinder = httpContext.RequestServices.GetRequiredService<HttpExceptionStatusCodeFinder>();
+            var jsonSerializer = httpContext.RequestServices.GetRequiredService<IJsonSerializer>();
+
+            httpContext.Response.Clear();
+            httpContext.Response.StatusCode = statusCodeFinder.GetStatusCode(httpContext, exception);
+            httpContext.Response.OnStarting(_clearCacheHeadersDelegate, httpContext.Response);
+            httpContext.Response.Headers.Add(new KeyValuePair<string, StringValues>("_AbpErrorFormat", "true"));  //TODO: Constant
+
+            await httpContext.Response.WriteAsync(
+                jsonSerializer.Serialize(
+                    new RemoteServiceErrorResponse(
+                        errorInfoConverter.Convert(exception)
+                    )
+                )
+            );
+        }
+
+        private Task ClearCacheHeaders(object state)
+        {
+            var response = (HttpResponse)state;
+
+            response.Headers[HeaderNames.CacheControl] = "no-cache";
+            response.Headers[HeaderNames.Pragma] = "no-cache";
+            response.Headers[HeaderNames.Expires] = "-1";
+            response.Headers.Remove(HeaderNames.ETag);
+
+            return Task.CompletedTask;
+        }
+    }
+}

src/Volo.Abp.AspNetCore.Mvc/Volo/Abp/AspNetCore/Mvc/ExceptionHandling/HttpExceptionStatusCodeFinder.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Net;
+using Microsoft.AspNetCore.Http;
+using Volo.Abp.Authorization;
+using Volo.Abp.DependencyInjection;
+using Volo.Abp.Domain.Entities;
+using Volo.Abp.Validation;
+
+namespace Volo.Abp.AspNetCore.Mvc.ExceptionHandling
+{
+    public class HttpExceptionStatusCodeFinder : ITransientDependency
+    {
+        public virtual int GetStatusCode(HttpContext httpContext, Exception exception)
+        {
+            if (exception is AbpAuthorizationException)
+            {
+                return httpContext.User.Identity.IsAuthenticated
+                    ? (int)HttpStatusCode.Forbidden
+                    : (int)HttpStatusCode.Unauthorized;
+            }
+
+            if (exception is AbpValidationException)
+            {
+                return (int)HttpStatusCode.BadRequest;
+            }
+
+            if (exception is EntityNotFoundException)
+            {
+                return (int)HttpStatusCode.NotFound;
+            }
+
+            return (int)HttpStatusCode.InternalServerError;
+        }
+    }
+}

src/Volo.Abp.AspNetCore.Mvc/Volo/Abp/AspNetCore/Mvc/Uow/AbpUnitOfWorkMiddleware.cs

@@ -1,5 +1,4 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
 using Volo.Abp.Uow;
 
@@ -8,15 +7,17 @@ namespace Volo.Abp.AspNetCore.Mvc.Uow
     public class AbpUnitOfWorkMiddleware
     {
         private readonly RequestDelegate _next;
+        private readonly IUnitOfWorkManager _unitOfWorkManager;
 
-        public AbpUnitOfWorkMiddleware(RequestDelegate next)
+        public AbpUnitOfWorkMiddleware(RequestDelegate next, IUnitOfWorkManager unitOfWorkManager)
         {
             _next = next;
+            _unitOfWorkManager = unitOfWorkManager;
         }
 
-        public async Task Invoke(HttpContext httpContext, IUnitOfWorkManager unitOfWorkManager)
+        public async Task Invoke(HttpContext httpContext)
         {
-            using (var uow = unitOfWorkManager.Reserve(AbpUowActionFilter.UnitOfWorkReservationName))
+            using (var uow = _unitOfWorkManager.Reserve(AbpUowActionFilter.UnitOfWorkReservationName))
             {
                 await _next(httpContext);
                 await uow.CompleteAsync(httpContext.RequestAborted);

src/Volo.Abp.AspNetCore.Mvc/Volo/Abp/AspNetCore/Mvc/Uow/AbpUowActionFilter.cs

@@ -1,6 +1,8 @@
 using System;
 using System.Net.Http;
+using System.Reflection;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc.Abstractions;
 using Microsoft.AspNetCore.Mvc.Filters;
 using Microsoft.Extensions.Options;
@@ -33,6 +35,8 @@ namespace Volo.Abp.AspNetCore.Mvc.Uow
             var methodInfo = context.ActionDescriptor.GetMethodInfo();
             var unitOfWorkAttr = UnitOfWorkHelper.GetUnitOfWorkAttributeOrNull(methodInfo);
 
+            SetAbpActionInfoToHttpContext(context.HttpContext, methodInfo);
+
             if (unitOfWorkAttr?.IsDisabled == true)
             {
                 await next();
@@ -62,6 +66,14 @@ namespace Volo.Abp.AspNetCore.Mvc.Uow
             }
         }
 
+        private static void SetAbpActionInfoToHttpContext(HttpContext context, MethodInfo methodInfo)
+        {
+            context.Items["_AbpActionInfo"] = new AbpActionInfoInHttpContext
+            {
+                IsObjectResult = ActionResultHelper.IsObjectResult(methodInfo.ReturnType)
+            };
+        }
+
         private UnitOfWorkOptions CreateOptions(ActionExecutingContext context, UnitOfWorkAttribute unitOfWorkAttribute)
         {
             var options = new UnitOfWorkOptions();

src/Volo.Abp/Volo/Abp/Uow/UnitOfWorkAttribute.cs

@@ -1,7 +1,5 @@
 using System;
 using System.Data;
-using System.Threading;
-using JetBrains.Annotations;
 
 namespace Volo.Abp.Uow
 {

test/Volo.Abp.AspNetCore.Mvc.Tests/Volo/Abp/AspNetCore/App/SimpleController.cs

@@ -14,5 +14,10 @@ namespace Volo.Abp.AspNetCore.App
         {
             return View();
         }
+
+        public ActionResult ExceptionOnRazor()
+        {
+            return View();
+        }
     }
 }

test/Volo.Abp.AspNetCore.Mvc.Tests/Volo/Abp/AspNetCore/App/Views/Simple/ExceptionOnRazor.cshtml

@@ -0,0 +1,5 @@
+@using Volo.Abp.Ui
+<h2>Exception test</h2>
+@{
+    throw new UserFriendlyException("test exception!");
+}

test/Volo.Abp.AspNetCore.Mvc.Tests/Volo/Abp/AspNetCore/Mvc/SimpleController_Tests.cs

@@ -1,6 +1,7 @@
 using System.Threading.Tasks;
 using Shouldly;
 using Volo.Abp.AspNetCore.App;
+using Volo.Abp.Ui;
 using Xunit;
 
 namespace Volo.Abp.AspNetCore.Mvc
@@ -26,5 +27,16 @@ namespace Volo.Abp.AspNetCore.Mvc
 
             result.Trim().ShouldBe("<h2>About</h2>");
         }
+
+        [Fact]
+        public async Task ActionResult_ViewResult_Exception()
+        {
+            await Assert.ThrowsAsync<UserFriendlyException>(async () =>
+            {
+                await GetResponseAsStringAsync(
+                    GetUrl<SimpleController>(nameof(SimpleController.ExceptionOnRazor))
+                );
+            });
+        }
     }
 }

test/Volo.Abp.AspNetCore.Mvc.Tests/Volo/Abp/AspNetCore/Mvc/Uow/UnitOfWorkMiddleware_Exception_Rollback_Tests.cs

@@ -1,7 +1,10 @@
-using System.Net;
+using System.Linq;
+using System.Net;
 using System.Threading.Tasks;
+using Microsoft.Extensions.DependencyInjection;
 using Shouldly;
 using Volo.Abp.Http;
+using Volo.Abp.Json;
 using Xunit;
 
 namespace Volo.Abp.AspNetCore.Mvc.Uow
@@ -19,7 +22,14 @@ namespace Volo.Abp.AspNetCore.Mvc.Uow
         [Fact]
         public async Task Should_Gracefully_Handle_Exceptions_On_Complete()
         {
-            var result = await GetResponseAsObjectAsync<RemoteServiceErrorResponse>("/api/unitofwork-test/ExceptionOnComplete", HttpStatusCode.InternalServerError);
+            var response = await GetResponseAsync("/api/unitofwork-test/ExceptionOnComplete", HttpStatusCode.InternalServerError);
+
+            response.Headers.GetValues("_AbpErrorFormat").FirstOrDefault().ShouldBe("true");
+
+            var resultAsString = await response.Content.ReadAsStringAsync();
+
+            var result = ServiceProvider.GetRequiredService<IJsonSerializer>().Deserialize<RemoteServiceErrorResponse>(resultAsString);
+
             result.Error.ShouldNotBeNull();
             result.Error.Message.ShouldBe(TestUnitOfWorkConfig.ExceptionOnCompleteMessage);
         }