Spring-boot authentication - spring

Question

I have few Spring-boot controller classes to expose few rest web-services. Whenever some user tries to access any of those services, I need to invoke an web-service to check whether the user (user id will be passed as RequestHeader) is authorized or not. If not authorised, need to display an error page (freemarker template) to the user.
I don't want to write a method which will invoke the authentication webservice and call that from each controller methods and throw an exception and redirect the user to the access denied error page using #ControllerAdvice as here I have to call the method from all controller methods.
I'm not sure whether I can use WebSecurityConfigurerAdapter/AuthenticationManagerBuilder to call the webservice and do the validation.
I'm looking for some solution where I would write an interceptor and spring-boot will invoke the webservice before calling the controller classes and will be able to redirect to the error page, if validation fails.

Answer 1

As a recommendation, take a few minutes for reading about Spring Security (https://projects.spring.io/spring-security/), you must configure it and probably you will spend more time than expected, anyway you have so much more profits than make security by ourself.
Benefits are things like:
#PreAuthorize("hasRole('ROLE_USER')")
On every place you can get the user logged through the SecurityContext with something like:
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
String currentPrincipalName = authentication.getName();
The way SpringSecurity authenticate users is with JWT (JsonWebToken) this is a really nice way because you can pass and retrieve all information you want:
public class CustomTokenEnhancer implements TokenEnhancer {
#Override
public OAuth2AccessToken enhance(OAuth2AccessToken accessToken, OAuth2Authentication authentication) {
User user = (User) authentication.getPrincipal();
final Map<String, Object> additionalInfo = new HashMap<>();
additionalInfo.put("customInfo", "some_stuff_here");
additionalInfo.put("authorities", user.getAuthorities());
((DefaultOAuth2AccessToken) accessToken).setAdditionalInformation(additionalInfo);
return accessToken;
}
}
And you can forget every possible problem (bad authentication, phishing, xss or csrf..) because it works with public/private key and secrets, so anyone can create a token.