Error when trying to retrieve BusinessPartnerUUID

Question

I've followed this deep dive blog 12. Deep Dive 12 It ran okay. And I am more interested in BusinessPartnerUUID, so I modify the file service-model.cds.

using API_BUSINESS_PARTNER as bp from './external/csn/API_BUSINESS_PARTNER';

service CrudService{

 @cds.persistence.skip
 Entity BusinessPartner as projection on bp.A_BusinessPartnerType{
   BusinessPartner,
   LastName,
   FirstName,
   BusinessPartnerCategory,
   BusinessPartnerUUID
  };
}

However, when I run this time, the service returns

The type 'class java.lang.String' of the value object is not supported.

As I do some googling, it leads me to this method Method internalValueToString

This is handled by the application programming model What can I do in this case to resolving the error? Thanks

Answer 1

I could reproduce your issue. It appears that the used Olingo lib has a problem with the type conversion of the UUID field. However I am not sure yet what causes the problem.

For the moment you can do the following:

Adjust the service definition by referring to a custom Business Partner entity definition instead. This is the same approach as in Step 3. of the Deep Dive.

service.cds:

using my.app from '../db/data-model';

service CrudService {
 @cds.persistence.skip
 entity BusinessPartner as projection on bookshop.BusinessPartners;
}

data-model.cds

entity BusinessPartners {
 key BusinessPartner : String(10);
 LastName: String(40);
 FirstName: String(40);
 BusinessPartnerUUID: String(36);
}

The UUID Field is of type CDS UUID and translates to OData EDM UUID field -> String(36).

Hope this was helpful.