How do I get the Session Object in Spring?

Question

I am relatively new to Spring and Spring security.

I was attempting to write a program where I needed to authenticate a user at the server end using Spring security,

I came up with the following:

public class CustomAuthenticationProvider extends AbstractUserDetailsAuthenticationProvider{
    @Override
    protected void additionalAuthenticationChecks(UserDetails userDetails, UsernamePasswordAuthenticationToken usernamePasswordAuthenticationToken)
                    throws AuthenticationException
    {
        System.out.println("Method invoked : additionalAuthenticationChecks isAuthenticated ? :"+usernamePasswordAuthenticationToken.isAuthenticated());
    }

    @Override
    protected UserDetails retrieveUser(String username,UsernamePasswordAuthenticationToken authentication) throws AuthenticationException 
    {
        System.out.println("Method invoked : retrieveUser");
        //so far so good, i can authenticate user here, and throw exception if not authenticated!!
        //THIS IS WHERE I WANT TO ACCESS SESSION OBJECT
    }
}

My usecase is that when a user is authenticated, I need to place an attribute like:

session.setAttribute("userObject", myUserObject);

myUserObject is an object of some class that I can access throughout my server code across multiple user requests.

Answer 1

Your friend here is org.springframework.web.context.request.RequestContextHolder

// example usage
public static HttpSession session() {
    ServletRequestAttributes attr = (ServletRequestAttributes) RequestContextHolder.currentRequestAttributes();
    return attr.getRequest().getSession(true); // true == allow create
}

This will be populated by the standard spring mvc dispatch servlet, but if you are using a different web framework you have add org.springframework.web.filter.RequestContextFilter as a filter in your web.xml to manage the holder.

EDIT: just as a side issue what are you actually trying to do, I'm not sure you should need access to the HttpSession in the retieveUser method of a UserDetailsService. Spring security will put the UserDetails object in the session for you any how. It can be retrieved by accessing the SecurityContextHolder:

public static UserDetails currentUserDetails(){
    SecurityContext securityContext = SecurityContextHolder.getContext();
    Authentication authentication = securityContext.getAuthentication();
    if (authentication != null) {
        Object principal = authentication.getPrincipal();
        return principal instanceof UserDetails ? (UserDetails) principal : null;
    }
    return null;
}