How to validate Spring #PathVariable properties first? - spring

Question

I have the following PUT method in my Spring Controller class. There is a parameter annotated with #PathVariable. There is another parameter annotated with #RequestBody #Valid. The problem is RequestBody is getting validated first and the method returns in case of exception. But I want #Pathvariable to be validated first and return in case of exception.
#RestController
#Validated
#RequestMapping(value = "/v1/order", produces = MediaType.APPLICATION_JSON_VALUE)
public class OrderMappingController {
#PutMapping(value = "/{id}/order-mapping", produces = MediaType.APPLICATION_JSON_VALUE, consumes = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity<?> UpdateOrderMapping(#PathVariable(value = "id") #NotBlank(message = "InvalidID")
#ValidOrderId String id,
#RequestBody #Valid OrderMappingRequest request) {
//...
}
}
Thanks in Advance!

Answer 1

You can write custom annotation and validator to validate the #Pathvariable
#RestController
#Validated
#RequestMapping(value = "/v1/order", produces = MediaType.APPLICATION_JSON_VALUE)
public class OrderMappingController {
#PutMapping(value = "/{id}/order-mapping", produces = MediaType.APPLICATION_JSON_VALUE, consumes = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity<?> UpdateOrderMapping(#PathVariable(value = "id") #OrderId String id,
#RequestBody #Valid OrderMappingRequest request) {
//...
}
}
Create custom annotation OrderId which can validate with custom validator class OrderIdValidator
#Constraint(validatedBy = OrderIdValidator.class)
#Retention(RetentionPolicy.RUNTIME)
#Target({ ElementType.FIELD, ElementType.METHOD,PARAMETER })
public #interface OrderId{
public String message() default "order id not found ";
public Class<?>[] groups() default {};
public Class<? extends Payload>[] payload() default{};
}
Then you can write the custom validator class which can check the business logic if the id is present in db or any other validation
public class OrderValidator implements ConstraintValidator<OrderId, String> {
#Autowired
private OrderRepository repository;
#Override
public boolean isValid(String value, ConstraintValidatorContext context) {
return (repository.existsByPeriod(value));
}
}

Answer 2

I suggest to try a different approach. Try not to annotate #Valid on your OrderMappingRequest, then implement a custom org.springframework.validation.Validator for your OrderMappingRequest bean which will then be injected and invoke in your OrderMappingController#UpdateOrderMapping method.
public class OrderMappingController {
#Autowired
private OrderMappingRequestValidator validator
#PutMapping("/{id}/order-mapping")
public ResponseEntity<?> UpdateOrderMapping(#PathVariable
#NotBlank(message = "InvalidID")
#ValidOrderId String id,
#RequestBody OrderMappingRequest request,
BindingResult result) {
validator.validate(request, result);
if(result.hasErrors()){
... do stuff or throw
}
}
}