Add property path to custom validation in Micronaut - kotlin

Question

Given the below, working validator factory, is it possible somehow to manipulate propertyPath? When debugging, I can see propertyPath inside io.micronaut.validation.validator.DefaultValidator$DefaultConstraintValidatorContext.
Motivation for doing so, is that some fields are conditionally required, and I need to put validation annotation on class-level, but then propertyPath is set to class, not to the actual fields with validation errors. When returning validation errors to API-clients, it would be nice to have correct property name for validation errors.
import io.micronaut.context.annotation.Factory
import io.micronaut.validation.validator.constraints.ConstraintValidator
import jakarta.inject.Singleton
import no.mycompany.myapp.web.config.UiConfig
import no.mycompany.myapp.web.viewmodel.MyExampleFormVm
#Factory
class ExampleValidatorFactory(private val uiConfig: UiConfig) {
#Singleton
fun validForm(): ConstraintValidator<ValidForm, MyExampleFormVm> = ConstraintValidator { value, _, context ->
val formTypeFromConfig = uiConfig.formTypes.first { it.id == value.formType }
if (formTypeFromConfig.labelSubCompanyId != null && value.subCompanyId == null) {
context.messageTemplate("Form requires one or more sub-company-ids")
// TODO: set propertyPath to "subCompanyId"
return#ConstraintValidator false
}
if (formTypeFromConfig.labelCompanyId != null && value.companyId == null) {
context.messageTemplate("Form requires company-id")
// TODO: set propertyPath to "companyId"
return#ConstraintValidator false
}
true
}
}
Annotation
import javax.validation.Constraint
#Retention(AnnotationRetention.RUNTIME)
#Constraint(validatedBy = [])
annotation class ValidForm(
val message: String = "Invalid form ({validatedValue})"
)
Example bean to validate:
import io.micronaut.core.annotation.Introspected
import javax.validation.constraints.NotBlank
import javax.validation.constraints.Pattern
#Introspected
#ValidForm
data class MyExampleFormVm(
#field:NotBlank
val formType: String = "",
#field:Pattern(regexp = "[8|9]\\d{8}")
val companyId: String? = null,
#field:Pattern(regexp = "[8|9]\\d{8}")
val subCompanyId: String? = null
)
This is my custom ConstraintExceptionHandler. I want it.propertyPath.lastOrNull()?.name to return e.g. "subCompanyId".
import io.micronaut.context.annotation.Replaces
import io.micronaut.context.annotation.Requires
import io.micronaut.http.HttpRequest
import io.micronaut.http.HttpResponse
import io.micronaut.http.HttpStatus
import io.micronaut.http.annotation.Produces
import io.micronaut.http.server.exceptions.response.ErrorResponseProcessor
import io.micronaut.validation.exceptions.ConstraintExceptionHandler
import jakarta.inject.Singleton
import java.time.Instant
import java.util.*
import javax.validation.ConstraintViolationException
#Produces
#Singleton
#Replaces(ConstraintExceptionHandler::class)
#Requires(classes = [ConstraintViolationException::class, ConstraintExceptionHandler::class])
class CustomConstraintExceptionHandler(responseProcessor: ErrorResponseProcessor<*>) :
ConstraintExceptionHandler(responseProcessor) {
override fun handle(request: HttpRequest<*>, exception: ConstraintViolationException): HttpResponse<*> =
HttpResponse.badRequest(
ApiError(
timestamp = Instant.now().toEpochMilli(),
httpStatusCode = HttpStatus.BAD_REQUEST.code,
errorType = ApiErrorType.VALIDATION_ERROR,
url = request.path,
validationErrors = exception.constraintViolations
.associate { (it.propertyPath.lastOrNull()?.name ?: FALLBACK_PROPERTY_PATH) to it.message }
))
companion object {
const val FALLBACK_PROPERTY_PATH = "ROOT"
}
}
---
import com.fasterxml.jackson.annotation.JsonInclude
import io.micronaut.core.annotation.Introspected
#Introspected
#JsonInclude(value = JsonInclude.Include.NON_NULL)
data class ApiError(
val timestamp: Long,
val httpStatusCode: Int,
val errorType: ApiErrorType,
val url: String,
val validationErrors: Map<String, String>? = null
)
enum class ApiErrorType {
VALIDATION_ERROR,
SYSTEM_ERROR;
}
Question from #Bonatti
If it.propertyPath.lastOrNull() is null, on the Handler, then that is
weird.
If you do like this, resultMap will contain an entry with key="ROOT".
val exampleForm = MyExampleFormVm(
formType = "SomeValue",
companyId = "912345678",
subCompanyId = null
)
val constraintViolations: Set<ConstraintViolation<MyExampleFormVm>> = validator.validate(exampleForm)
val resultMap = constraintViolations.associate { (it.propertyPath.lastOrNull()?.name ?: "ROOT") to it.message }
Environment: Micronaut 3.7.4