Spring boot : How could I customize the forbidden error json

Question

I was wondering if I could customize the following forbidden JSON error:

Actual Response

{
  "timestamp": "2018-09-26T06:11:05.047+0000",
  "status": 403,
  "error": "Forbidden",
  "message": "Access Denied",
  "path": "/api/rest/hello/me"
}

Custom Response - I get it when the user request does not have permissions.

{ 
  "code": 403,
  "message": "Access denied by the system",
  "status": "Failure"
}

My Web security class

@Configuration
@EnableGlobalMethodSecurity(prePostEnabled = true)
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

  @Autowired
  private JwtTokenProvider jwtTokenProvider;

  @Override
  protected void configure(HttpSecurity http) throws Exception {
    http.csrf().disable();
    http.sessionManagement().sessionCreationPolicy(SessionCreationPolicy.STATELESS);
    http.authorizeRequests()//
        .antMatchers("/rest/hello/signin").permitAll()//
        .anyRequest().authenticated();
    http.apply(new JwtTokenFilterConfigurer(jwtTokenProvider));
  @Bean
  public PasswordEncoder passwordEncoder() {
    return new BCryptPasswordEncoder(12);
  }
}

Answer 1

You can create custom handler using the Jackson ObjectMapper like this:

@Bean
public AccessDeniedHandler accessDeniedHandler() {
    return (request, response, ex) -> {
        response.setStatus(HttpServletResponse.SC_FORBIDDEN);
        response.setContentType(MediaType.APPLICATION_JSON_VALUE);

        ServletOutputStream out = response.getOutputStream();
        new ObjectMapper().writeValue(out, new MyCustomErrorDTO());
        out.flush();
    };
}

And configure your HttpSecurity like this:

http.exceptionHandling().accessDeniedHandler(accessDeniedHandler());

Also, you can try throw AuthenticationException:

@Bean
public AuthenticationFailureHandler failureHandler() {
    return (request, response, ex) -> { throw ex; };
}

And handle them in @RestControllerAdvice:

@RestControllerAdvice
public class AdviseController {

    @ExceptionHandler(AuthenticationException.class)
    @ResponseStatus(HttpStatus.FORBIDDEN)
    public MyCustomErrorDTO handleAuthenticationException(AuthenticationException ex) {
        return new MyCustomErrorDTO();
    }
}

But I'm not sure that it will work, you can check it out.