[CAUSEWAY-491] [Wish] Integrate JSR-349 validation.

• Type: Wish
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: core-1.2.0
• Component/s: Applib (programming model)
• Assignee: Unassigned
• Reporter: Daniel Keir Haywood
• Created: 13/Aug/13 07:17
• Updated: 29/Apr/22 15:15

Description

as per http://docs.jboss.org/hibernate/stable/validator/reference/en-US/html_single/

The reference implementation (Hibernate Validator) is Apache licensed [1].

~~~
Implementation: should not be too difficult; mostly a matter of writing some FacetFactories.

It may not make sense to use every feature of JSR-349...

• constructor parameters
• constraint groups

1. In Isis bootstrapping, get hold and cache the Validator. (This is thread-safe, so could perhaps be global; maybe as a new top-level component cf AuthorizationManager etc).

ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
validator = factory.getValidator();

and also

executableValidator = validator.forExecutables();

Validating a property change can be done using:

Set<ConstraintViolation<Car>> constraintViolations = validator.validateValue(
        Car.class,
        "manufacturer",
        null
);

assertEquals( 1, constraintViolations.size() );
assertEquals( "may not be null", constraintViolations.iterator().next().getMessage() );

(nb: using validator.validateProperty(...) would mean that the value has been applied already).

eg this would be a facet that implements ValidatingInteractionAdvisor and acts on a ValidityContext of type PropertyModifyContext. (eg subclass PropertyValidateFacetAbstract)

2. Validating a parameter of an action can be done using:

Car object = new Car( "Morris" );
Method method = Car.class.getMethod( "drive", int.class );
Object[] parameterValues = { 80 };
Set<ConstraintViolation<Car>> violations = executableValidator.validateParameters(
        object,
        method,
        parameterValues
);

assertEquals( 1, violations.size() );
Class<? extends Annotation> constraintType = violations.iterator()
        .next()
        .getConstraintDescriptor()
        .getAnnotation()
        .annotationType();
assertEquals( Max.class, constraintType );

This would be in a Facet that implements ValidatingInteractionAdvisor and acts on a ValidityContext of type ActionInvocationContext (eg subclass ActionValidationFacetAbstract)

~~~
There are also some new features that could be implemented:

3. validating the return value of an action:

Car object = new Car( "Morris" );
Method method = Car.class.getMethod( "getPassengers" );
Object returnValue = Collections.<Passenger>emptyList();
Set<ConstraintViolation<Car>> violations = executableValidator.validateReturnValue(
        object,
        method,
        returnValue
);

assertEquals( 1, violations.size() );
Class<? extends Annotation> constraintType = violations.iterator()
        .next()
        .getConstraintDescriptor()
        .getAnnotation()
        .annotationType();
assertEquals( Size.class, constraintType );

This would need to be done after the action has been invoked; if the constraint failed, then an exception would be thrown causing the transaction to be aborted. This might require a new subclass of ValidityContext, eg ActionReturnValueContext.

4. cf ISIS-479, all dirtied objects should be validated prior to commit.
a) we re-validate all properties (using the value of the property as the proposed value). This would be done using InteractionUtils, called from isAssociationValid with a ValidityContext of PropertyModifyContext.
b) we validate the object, ie InteractionUtils, with all with a ValidityContext of ObjectValidityContext.

We would then have a new facet, implementing ValidatingInteractionAdvisor and acting on an ObjectValidityContext (eg subclass ValidateObjectFacetAbstract); which should perform:

Set<ConstraintViolation<Car>> constraintViolations = validator.validate( car );

Issue Links

• Is contained by: CAUSEWAY-2695 [Duplicate] Add Java Bean Validation support