Spring MVC get authentication error

Question

How can I get user authentication error (bad username/password, disabled/locked/expired account) in @Controller and add this error to model attributes to show in Thymeleaf template? I handle it in WebSecurityConfigurerAdapter

http    
    .formLogin()
    .loginPage("/login")
    .failureUrl("/login/error")

and process in @Controller method

@RequestMapping("/login/error")
public String loginError(Model model) {
    model.addAttribute("loginError", true);
    return "login";
}

but what method parameter I should use to do this? It's possible with HttpSession (it contains authentication exception object), but I don't think it's a good idea.

Answer 1

You can print the authentication error message with the following Thymeleaf code:

<p data-th-if="${loginError == true && session.SPRING_SECURITY_LAST_EXCEPTION != null}"
   data-th-text="${session.SPRING_SECURITY_LAST_EXCEPTION.message}">
  Bad credentials.
</p>

No additional code in controller needed.