Implemented Soft Delete filter.

src/Volo.Abp.EntityFrameworkCore/Volo/Abp/EntityFrameworkCore/AbpDbContext.cs

@@ -22,6 +22,7 @@ namespace Volo.Abp.EntityFrameworkCore
         public Guid? CurrentTenantId => CurrentTenant?.Id;
 
         protected virtual bool IsMayHaveTenantFilterEnabled => true; //TODO: Change this when data filtering system is full implemented
+        protected virtual bool IsSoftDeleteFilterEnabled => true; //TODO: Change this when data filtering system is full implemented
 
         public ICurrentTenant CurrentTenant { get; set; }
 
@@ -115,7 +116,10 @@ namespace Volo.Abp.EntityFrameworkCore
                         CheckAndSetId(entry);
                         break;
                     case EntityState.Modified:
+                        HandleConcurrencyStamp(entry);
+                        break;
                     case EntityState.Deleted:
+                        CancelDeletionForSoftDelete(entry);
                         HandleConcurrencyStamp(entry);
                         break;
                 }
@@ -133,6 +137,18 @@ namespace Volo.Abp.EntityFrameworkCore
             entity.ConcurrencyStamp = Guid.NewGuid().ToString();
         }
 
+        protected virtual void CancelDeletionForSoftDelete(EntityEntry entry)
+        {
+            if (!(entry.Entity is ISoftDelete))
+            {
+                return;
+            }
+
+            entry.Reload();
+            entry.State = EntityState.Modified;
+            entry.Entity.As<ISoftDelete>().IsDeleted = true;
+        }
+
         protected virtual void CheckAndSetId(EntityEntry entry)
         {
             //Set GUID Ids
@@ -179,6 +195,18 @@ namespace Volo.Abp.EntityFrameworkCore
         {
             Expression<Func<TEntity, bool>> expression = null;
 
+            if (typeof(ISoftDelete).IsAssignableFrom(typeof(TEntity)))
+            {
+                /* This condition should normally be defined as below:
+                 * !IsSoftDeleteFilterEnabled || !((ISoftDelete) e).IsDeleted
+                 * But this causes a problem with EF Core (see https://github.com/aspnet/EntityFrameworkCore/issues/9502)
+                 * So, we made a workaround to make it working. It works same as above.
+                 */
+
+                Expression<Func<TEntity, bool>> softDeleteFilter = e => !((ISoftDelete)e).IsDeleted || ((ISoftDelete)e).IsDeleted != IsSoftDeleteFilterEnabled;
+                expression = expression == null ? softDeleteFilter : CombineExpressions(expression, softDeleteFilter);
+            }
+
             if (typeof(IMultiTenant).IsAssignableFrom(typeof(TEntity)))
             {
                 /* This condition should normally be defined as below:

src/Volo.Abp/Volo/Abp/ISoftDelete.cs

@@ -0,0 +1,16 @@
+namespace Volo.Abp
+{
+    /// <summary>
+    /// Used to standardize soft deleting entities.
+    /// Soft-delete entities are not actually deleted,
+    /// marked as IsDeleted = true in the database,
+    /// but can not be retrieved to the application normally.
+    /// </summary>
+    public interface ISoftDelete
+    {
+        /// <summary>
+        /// Used to mark an Entity as 'Deleted'. 
+        /// </summary>
+        bool IsDeleted { get; set; }
+    }
+}

test/Volo.Abp.EntityFrameworkCore.Tests/Migrations/20171026101049_Added_IsDeleted_To_Person.Designer.cs

@@ -0,0 +1,70 @@
+// <auto-generated />
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Metadata;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage;
+using Microsoft.EntityFrameworkCore.Storage.Internal;
+using System;
+using Volo.Abp.TestApp.Domain;
+using Volo.Abp.TestApp.EntityFrameworkCore;
+
+namespace Volo.Abp.EntityFrameworkCore.Tests.Migrations
+{
+    [DbContext(typeof(TestAppDbContext))]
+    [Migration("20171026101049_Added_IsDeleted_To_Person")]
+    partial class Added_IsDeleted_To_Person
+    {
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "2.0.0-rtm-26452");
+
+            modelBuilder.Entity("Volo.Abp.TestApp.Domain.Person", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd();
+
+                    b.Property<int>("Age");
+
+                    b.Property<bool>("IsDeleted");
+
+                    b.Property<string>("Name");
+
+                    b.Property<Guid?>("TenantId");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("People");
+                });
+
+            modelBuilder.Entity("Volo.Abp.TestApp.Domain.Phone", b =>
+                {
+                    b.Property<long>("Id")
+                        .ValueGeneratedOnAdd();
+
+                    b.Property<string>("Number");
+
+                    b.Property<Guid>("PersonId");
+
+                    b.Property<int>("Type");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("PersonId");
+
+                    b.ToTable("AppPhones");
+                });
+
+            modelBuilder.Entity("Volo.Abp.TestApp.Domain.Phone", b =>
+                {
+                    b.HasOne("Volo.Abp.TestApp.Domain.Person")
+                        .WithMany("Phones")
+                        .HasForeignKey("PersonId")
+                        .OnDelete(DeleteBehavior.Cascade);
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

test/Volo.Abp.EntityFrameworkCore.Tests/Migrations/20171026101049_Added_IsDeleted_To_Person.cs

@@ -0,0 +1,26 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+using System;
+using System.Collections.Generic;
+
+namespace Volo.Abp.EntityFrameworkCore.Tests.Migrations
+{
+    public partial class Added_IsDeleted_To_Person : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<bool>(
+                name: "IsDeleted",
+                table: "People",
+                type: "INTEGER",
+                nullable: false,
+                defaultValue: false);
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "IsDeleted",
+                table: "People");
+        }
+    }
+}

test/Volo.Abp.EntityFrameworkCore.Tests/Migrations/TestAppDbContextModelSnapshot.cs

@@ -27,6 +27,8 @@ namespace Volo.Abp.EntityFrameworkCore.Tests.Migrations
 
                     b.Property<int>("Age");
 
+                    b.Property<bool>("IsDeleted");
+
                     b.Property<string>("Name");
 
                     b.Property<Guid?>("TenantId");

test/Volo.Abp.EntityFrameworkCore.Tests/Volo/Abp/EntityFrameworkCore/Repositories/SoftDelete_Filter_Tests.cs

@@ -0,0 +1,26 @@
+using System.Linq;
+using Shouldly;
+using Volo.Abp.Domain.Repositories;
+using Volo.Abp.TestApp.Domain;
+using Xunit;
+
+namespace Volo.Abp.EntityFrameworkCore.Repositories
+{
+    public class SoftDelete_Filter_Tests : EntityFrameworkCoreTestBase
+    {
+        private readonly IRepository<Person> _personRepository;
+
+        public SoftDelete_Filter_Tests()
+        {
+            _personRepository = GetRequiredService<IRepository<Person>>();
+        }
+
+        [Fact]
+        public void Should_Not_Get_Deleted_Entities_By_Default()
+        {
+            var people = _personRepository.GetList();
+            people.Count.ShouldBe(1);
+            people.Any(p => p.Name == "Douglas").ShouldBeTrue();
+        }
+    }
+}

test/Volo.Abp.TestApp/Volo/Abp/TestApp/Domain/Person.cs

@@ -5,7 +5,7 @@ using Volo.Abp.MultiTenancy;
 
 namespace Volo.Abp.TestApp.Domain
 {
-    public class Person : AggregateRoot, IMultiTenant
+    public class Person : AggregateRoot, IMultiTenant, ISoftDelete
     {
         public virtual Guid? TenantId { get; set; }
 
@@ -15,6 +15,8 @@ namespace Volo.Abp.TestApp.Domain
 
         public virtual Collection<Phone> Phones { get; set; }
 
+        public bool IsDeleted { get; set; }
+
         private Person()
         {
             

test/Volo.Abp.TestApp/Volo/Abp/TestApp/TestDataBuilder.cs

@@ -30,6 +30,8 @@ namespace Volo.Abp.TestApp
 
             _personRepository.Insert(douglas);
 
+            _personRepository.Insert(new Person(Guid.NewGuid(), "John-Deleted", 33) { IsDeleted = true });
+
             var tenant1Person1 = new Person(Guid.NewGuid(), TenantId1 + "-Person1", 42, TenantId1);
             var tenant1Person2 = new Person(Guid.NewGuid(), TenantId1 + "-Person2", 43, TenantId1);