Weird validation error handling in Micronaut - validation

Question

I have a controller action to serve my react front-end. It requires the validation messages in the special format:
#Transactional
#Post( uri = '{/id}', consumes = MediaType.APPLICATION_JSON, produces = MediaType.APPLICATION_JSON )
HttpResponse save( #PathVariable #Nullable Long id, #Body Map body ){
def o = bindFromIdAndBody id, body
if( o.save( flush:true ) ){
log.info "version >> $o.version"
HttpResponse.ok o
}else{
log.info '-------------------------'
List errors = o.errors.fieldErrors.collect{ FieldError fe ->
fe.codes.findResult{ String c ->
messageSource.getMessage c, fe.arguments, null, Locale.default
} ?: fe.codes.last()
}
log.info "save failed for $o: $errors"
HttpResponse.badRequest( errors:errors )
}
}
When I call the action, I'm getting 400 Bad Request in my client, but instead of { errors:[ {..}, {..}, {..} ] style JSON, I see rather:
{
"message":"Validation Error(s) occurred during save() : Field error in object ... default message [Property [{0}] of class [{1}] cannot be blank]\r\n",
"path":"fullName",
"_links":{"self":{"href":"/person/42","templated":false}}
}
Also the else{} block is never reached, I don't get any further logs.
Any hints?

Answer 1

It appears, that in GORM configuration for Micronaut done via
compile 'io.micronaut.configuration:micronaut-hibernate-gorm'
the failOnError is set to true by default. That led to ValidationException being thrown on save() instead of populating o.errors.
To fix the issue I added the line
grails.gorm.failOnError: false
to my application.yml and now it's working like charm.