Spring Data Rest Validation Confusion

Question

Looking for some help with Spring data rest validation regarding proper handling of validation errors:

I\'m so confused with the docs regarding spring-data-rest vali

Answer 1

I think your problem is that the bean validation is happening too late - it is done on the JPA level before persist. I found that - unlike spring mvc - spring-data-rest is not doing bean validation when a controller method is invoked. You will need some extra configuration for this.

You want spring-data-rest to validate your bean - this will give you nice error messages responses and a proper http return code.

I configured my validation in spring-data-rest like this:

@Configuration
public class MySpringDataRestValidationConfiguration extends RepositoryRestConfigurerAdapter {

    @Bean
    @Primary
    /**
     * Create a validator to use in bean validation - primary to be able to autowire without qualifier
     */
    Validator validator() {
        return new LocalValidatorFactoryBean();
    }

    @Bean
    //the bean name starting with beforeCreate will result into registering the validator before insert
    public BeforeCreateCompanyValidator beforeCreateCompanyValidator() {
        return new BeforeCreateCompanyValidator();
    }

    @Override
    public void configureValidatingRepositoryEventListener(ValidatingRepositoryEventListener validatingListener) {
        Validator validator = validator();
        //bean validation always before save and create
        validatingListener.addValidator("beforeCreate", validator);
        validatingListener.addValidator("beforeSave", validator);
    }
}

When bean validation and/or my custom validator find errors I receive a 400 - bad request with a payload like this:

    Status = 400
    Error message = null
    Headers = {Content-Type=[application/hal+json]}
    Content type = application/hal+json
   Body = {
     "errors" : [ {
     "entity" : "siteWithAdminUser",
     "message" : "may not be null",
     "invalidValue" : "null",
     "property" : "adminUser"
     } ]
   }