Spring Boot REST @RequestParam not being Validated

Question

I have tried a number of examples from the net and cannot get Spring to validate my query string parameter. It doesn't seem execute the REGEX / fail.

package my.controller;  import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.RestController;  import javax.validation.Valid; import javax.validation.constraints.Pattern;  import static org.springframework.web.bind.annotation.RequestMethod.GET;  @RestController public class MyController {      private static final String VALIDATION_REGEX = "^[0-9]+(,[0-9]+)*$";      @RequestMapping(value = "/my/{id}", method = GET)     public myResonseObject getMyParams(@PathVariable("id") String id,                                        @Valid @Pattern(regexp = VALIDATION_REGEX)                                         @RequestParam(value = "myparam", required = true) String myParam) {          // Do Stuff!     }  } 

Current behaviour

PASS - /my/1?myparam=1 PASS - /my/1?myparam=1,2,3 PASS - /my/1?myparam= PASS - /my/1?myparam=1,bob 

Desired behaviour

PASS - /my/1?myparam=1 PASS - /my/1?myparam=1,2,3 FAIL - /my/1?myparam= FAIL - /my/1?myparam=1,bob 

Thanks

Answer 1

You need add @Validated to your class like this:

@RestController @Validated class Controller {   // ... } 

UPDATE:

you need to configure it properly.. add this bean to your context:

@Bean  public MethodValidationPostProcessor methodValidationPostProcessor() {       return new MethodValidationPostProcessor();  } 

Example to handle exception:

@ControllerAdvice @Component public class GlobalExceptionHandler {     @ExceptionHandler     @ResponseBody     @ResponseStatus(HttpStatus.BAD_REQUEST)     public Map handle(MethodArgumentNotValidException exception) {         return error(exception.getBindingResult().getFieldErrors()                 .stream()                 .map(FieldError::getDefaultMessage)                 .collect(Collectors.toList()));     }       @ExceptionHandler     @ResponseBody     @ResponseStatus(HttpStatus.BAD_REQUEST)     public Map handle(ConstraintViolationException exception) {         return error(exception.getConstraintViolations()                 .stream()                 .map(ConstraintViolation::getMessage)                 .collect(Collectors.toList()));     }      private Map error(Object message) {         return Collections.singletonMap("error", message);     } }