In dialogs many input validation rules are used. Some (input) validations will be defined within the domain layer and used within dialogs (interface layer), others are only defined and used within dialogs (e.g. correct birthday, telephone numbers, etc.). Validation rules defined within the domain layer will cause coupling between dialogs and business rules which will leads to many undesirable effects.
Context
Input validations and suport attributes.
op een plek definieren zodat onderhoud eenvoudig is. Weinig werkt.
Validatie service
Input validation
(front-end only)
Business rule validation
(defined in domain, also used in front-end)
Correct telephone number
X
Correct birthday
X
Policy
X
Eigenschap
Omschrijving
Kennis ontsluiting
Implicit vs explicit call
Truth maintenance
Implementatie kenmerken
Testable
Front-end and business rules are independently testable.
Maintainable
Business rules are easy to maintain. Front-end and domain logic are not intertwined.
Out of the box
Problem
Content of a value list changes more often compared to the application which uses the value list. Seperating application behaviour from maintenance of value list content which could be depend on external resources.
Solutions
Voor de oplossing wordt rekening gehouden met de kenmerken die benoemd zijn in de tabel onder "Context".
Er zijn verschillende oplossingen mogelijk waarbij de bovenstaande kenmerken in meer- of mindere mate gerealiseerd kunnen worden. Per geval dient de best passende oplossing te worden gekozen. In de tabel hieronder worden de belangrijkste eigenschappen getoond en hoe elke oplossing daarop scoort.