how do I cancel an update for an entity in RESTier that fails custom validation logic?

Question

I am using RESTier 0.4.0-rc2.

With OnUpdating... if the entity fails my custom validation logic I have no way to cancel the update, and return a custom error.

With CanUpdate... I can cancel the update by returning false, but there is no entity passed in to apply my custom logic to, and no way to provide a custom error.

Seems like a fundamental flaw, am I missing something?

Answer 1

Even you already have the answer, I would like to provide it for others.

If you want some customized logic for update validation, you can implement a class implements interface IChangeSetEntryValidator, validate in any logic you want, and then add logic like

DataModificationEntry dataModificationEntry = entry as DataModificationEntry;
var entity = dataModificationEntry.Entity;

 // Customized validate logic and if error, add a error validation result.
validationResults.Add(new ChangeSetValidationResult()
{
    Id = dataModificationEntry.EntitySetName+ dataModificationEntry.EntityKey,
    Message = "Customized error",
    Severity = ChangeSetValidationSeverity.Error,
    Target = entity
});

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