Merge pull request #322 from delegateas/feature/311-nullreferenceexception-when-update-plugi

Fix NullReferenceException when plugins with post-images fire via Multiple requests

Author: mkholt

src/XrmMockup365/Core.cs

@@ -1316,7 +1316,7 @@ private Tuple<object, string, Guid> GetEntityInfo(OrganizationRequest request)
         }
 
 
-        private Entity TryRetrieve(EntityReference reference)
+        internal Entity TryRetrieve(EntityReference reference)
         {
             return db.GetEntityOrNull(reference)?.CloneEntity();
         }

src/XrmMockup365/Plugin/PluginManager.cs

@@ -347,6 +347,7 @@ public void TriggerSync(string operation, ExecutionStage stage,
                     postImage != null ? new EntityImageCollection { { "PostImage", postImage } } : new EntityImageCollection()
                 };
 
+
                 TriggerSyncInternal(multipleOperation.ToString(), stage, entityCollection, null, null, multiplePluginContext, core, executionOrderFilter);
             }
 

src/XrmMockup365/Plugin/PluginTrigger.cs

@@ -144,7 +144,8 @@ private void CheckSpecialRequest()
 
         private Entity AddPostImageAttributesToEntity(Entity entity, Entity preImage, Entity postImage)
         {
-            if (Operation.Matches(EventOperation.Update) && Stage == ExecutionStage.PostOperation)
+            if (Operation.Matches(EventOperation.Update) && Stage == ExecutionStage.PostOperation
+                && preImage != null && postImage != null)
             {
                 var shadowAddedAttributes = postImage.Attributes.Where(a => !preImage.Attributes.ContainsKey(a.Key) && !entity.Attributes.ContainsKey(a.Key));
                 entity = entity.CloneEntity();
@@ -215,7 +216,7 @@ private PluginContext CreatePluginContext(PluginContext pluginContext, Guid guid
                 {
                     thisPluginContext.PostEntityImages.Add(image.ImageName, postImage.CloneEntity(Metadata.GetMetadata(postImage.LogicalName), cols));
                 }
-                if (preImage != null && imageType == ImageType.PreImage || imageType == ImageType.Both)
+                if (preImage != null && (imageType == ImageType.PreImage || imageType == ImageType.Both))
                 {
                     thisPluginContext.PreEntityImages.Add(image.ImageName, preImage.CloneEntity(Metadata.GetMetadata(preImage.LogicalName), cols));
                 }

tests/TestPluginAssembly365/Plugins/ContactPostImageOnUpdatePlugin.cs

@@ -0,0 +1,29 @@
+using DG.XrmFramework.BusinessDomain.ServiceContext;
+using XrmPluginCore;
+using XrmPluginCore.Enums;
+using Microsoft.Xrm.Sdk;
+
+namespace DG.Some.Namespace
+{
+    public class ContactPostImageOnUpdatePlugin : Plugin
+    {
+        public ContactPostImageOnUpdatePlugin()
+        {
+#pragma warning disable CS0618 // Type or member is obsolete - disabled for testing purposes
+            RegisterPluginStep<Contact>(
+                EventOperation.Update,
+                ExecutionStage.PostOperation,
+                Execute)
+                .AddFilteredAttributes(c => c.Description)
+                .WithPostImage();
+#pragma warning restore CS0618
+        }
+
+        protected void Execute(LocalPluginContext localContext)
+        {
+            // Access post-images to verify they don't throw NullReferenceException
+            var postImages = localContext.PluginExecutionContext.PostEntityImages;
+            localContext.PluginExecutionContext.SharedVariables["PostImageCount"] = postImages.Count;
+        }
+    }
+}

tests/XrmMockup365Test/TestMultipleRequestPluginImages.cs

@@ -0,0 +1,90 @@
+using System.Linq;
+using Microsoft.Xrm.Sdk;
+using Microsoft.Xrm.Sdk.Messages;
+using Microsoft.Xrm.Sdk.Query;
+using DG.XrmFramework.BusinessDomain.ServiceContext;
+using Xunit;
+
+namespace DG.XrmMockupTest
+{
+    public class TestMultipleRequestPluginImages : UnitTestBase
+    {
+        public TestMultipleRequestPluginImages(XrmMockupFixture fixture) : base(fixture) { }
+
+        [Fact]
+        public void UpdateMultiple_TriggersUpdatePostOpPlugin_WithPostImages()
+        {
+            // Arrange: create contacts
+            var contact1Id = orgGodService.Create(new Contact { FirstName = "Alice", LastName = "One" });
+            var contact2Id = orgGodService.Create(new Contact { FirstName = "Bob", LastName = "Two" });
+
+            // Act: UpdateMultiple - this previously threw NullReferenceException
+            // because plugins with post-images received null images from the Multiple->Single cross-trigger
+            var updateMultiple = new UpdateMultipleRequest
+            {
+                Targets = new EntityCollection
+                {
+                    EntityName = Contact.EntityLogicalName,
+                    Entities =
+                    {
+                        new Contact(contact1Id) { Description = "updated-1" },
+                        new Contact(contact2Id) { Description = "updated-2" },
+                    }
+                }
+            };
+
+            // Should not throw NullReferenceException
+            orgAdminService.Execute(updateMultiple);
+
+            // Assert: entities were updated
+            var retrieved1 = Contact.Retrieve(orgAdminService, contact1Id);
+            var retrieved2 = Contact.Retrieve(orgAdminService, contact2Id);
+            Assert.Equal("updated-1", retrieved1.Description);
+            Assert.Equal("updated-2", retrieved2.Description);
+        }
+
+        [Fact]
+        public void CreateMultiple_DoesNotCrash()
+        {
+            var createMultiple = new CreateMultipleRequest
+            {
+                Targets = new EntityCollection
+                {
+                    EntityName = Contact.EntityLogicalName,
+                    Entities =
+                    {
+                        new Contact { FirstName = "Charlie", LastName = "Three" },
+                        new Contact { FirstName = "Diana", LastName = "Four" },
+                    }
+                }
+            };
+
+            // Should not throw
+            var response = (CreateMultipleResponse)orgAdminService.Execute(createMultiple);
+            Assert.NotNull(response);
+        }
+
+        [Fact]
+        public void SingleUpdate_TriggersUpdateMultiplePlugin()
+        {
+            // The SetCityOnCreateUpdateMultiple plugin is registered on UpdateMultiple/PreOperation
+            // and should fire via the Single->Multiple cross-trigger
+            var contactId = orgGodService.Create(new Contact { FirstName = "Eve", Address2_City = "Berlin" });
+
+            orgAdminService.Update(new Contact(contactId) { FirstName = "Eve-Updated" });
+
+            var retrieved = Contact.Retrieve(orgAdminService, contactId);
+            Assert.Equal("Copenhagen", retrieved.Address2_City);
+        }
+
+        [Fact]
+        public void SingleCreate_TriggersCreateMultiplePlugin()
+        {
+            // The SetCityOnCreateUpdateMultiple plugin is registered on CreateMultiple/PreOperation
+            var contactId = orgAdminService.Create(new Contact { FirstName = "Frank" });
+
+            var retrieved = Contact.Retrieve(orgAdminService, contactId);
+            Assert.Equal("Copenhagen", retrieved.Address2_City);
+        }
+    }
+}