[2.0] ChangeSets and Data Validation

In CustomizedValidator implementation, LocalValues reflects the change requests and Resource reflects the object's last state as expected, but the OriginalValues doesn't get filled which makes it impossible to compare old and new data for validation purposes.

csproj

<PackageReference Include="Microsoft.Restier.AspNetCore" Version="1.0.0-ci-20211128-172920" />
<PackageReference Include="Microsoft.Restier.EntityFrameworkCore" Version="1.0.0-ci-20211128-172920" />

startup.cs

routeServices.AddChainedService<IChangeSetItemFilter, CustomizedSubmitProcessor>();

CustomizedValidator.cs

public class CustomizedValidator : IChangeSetItemValidator
{
	private IChangeSetItemValidator Inner { get; set; }

	public Task ValidateChangeSetItemAsync(SubmitContext context, ChangeSetItem item, Collection<ChangeSetItemValidationResult> validationResults, CancellationToken cancellationToken)
	{
		if (item is not DataModificationItem dataModificationItem)
		{
			return Inner.ValidateChangeSetItemAsync(context, item, validationResults, cancellationToken);
		}

		object entity = dataModificationItem.Resource;
		bool isNewRequest = dataModificationItem.OriginalValues == null && dataModificationItem.ResourceKey == null;
		bool isUpdateRequest = dataModificationItem.OriginalValues != null && dataModificationItem.LocalValues != null;
		bool isDeleteRequest = dataModificationItem.LocalValues == null;

		if (isUpdateRequest && entity is Organization organization)
		{
			dataModificationItem.LocalValues.TryGetValue("ParentId",out object localValueParentId);
			dataModificationItem.OriginalValues.TryGetValue("ParentId", out object originalValueParentId);
			bool changeExists = localValueParentId is not null && originalValueParentId is not null && localValueParentId != originalValueParentId;

			if (organization.ParentId is not null && !changeExists)
			{
				var changeSetValidationResult = new ChangeSetItemValidationResult
				{
					Message = "You can not change this record's `ParentId`.  It is not `null`.",
					Severity = EventLevel.Error,
					PropertyName = dataModificationItem.ResourceSetName + dataModificationItem.ResourceKey,
					Target = entity
				};
				validationResults.Add(changeSetValidationResult);
			}
			using (var service = context.GetApiService<SmartProcureApi>())
			{
				var existingRecordParentId = service.DbContext.Organizations.Where(o => o.Id.Equals(organization.Id)).FirstOrDefault()?.ParentId;
				if (existingRecordParentId != null && organization.ParentId!=existingRecordParentId)
				{

				}
			}
		}

		return Inner.ValidateChangeSetItemAsync(context, item, validationResults, cancellationToken);
	}
}

Start with CustomizedValidator.cs and the DataModificationItem values described in the report, using the csproj package references and startup.cs registration to reproduce the change-set validation path. Inspect why OriginalValues is null while LocalValues and Resource are populated; done means validators can compare old and new data for update requests.