Use custom validation responses with fluent validation

Question

Hello I am trying to get custom validation response for my webApi using .NET Core.

Here I want to have response model like

[{
  ErrorCode:
  ErrorFi         


        

Answer 1

Refer this link for answer: https://github.com/JeremySkinner/FluentValidation/issues/548

Solution:

What I've done is that I created a basevalidator class which inherited both IValidatorInterceptor and AbstractValidator. In afterMvcvalidation method if validation is not successful, I map the error from validationResult to my custom response object and throw Custom exception which I catch in my exception handling middleware and return response.

On Serialization issue where controller gets null object:

modelstate.IsValid will be set to false when Json Deserialization fails during model binding and Error details will be stored in ModelState. [Which is what happened in my case]

Also due to this failure, Deserialization does not continue further and gets null object in controller method.

As of now, I have created a hack by setting serialization errorcontext.Handled = true manually and allowing my fluentvalidation to catch the invalid input.

https://www.newtonsoft.com/json/help/html/SerializationErrorHandling.htm [defined OnErrorAttribute in my request model].

I am searching for a better solution but for now this hack is doing the job.