How can I have list of all users logged in (via spring security) my web application

Question

I\'m using spring security in my web application, and now I want to have a list of all users who are logged in my program.

How can I have access to that list? Aren\'

Answer 1

For accessing the list of all logged in users you need to inject SessionRegistry instance to your bean.

@Autowired
@Qualifier("sessionRegistry")
private SessionRegistry sessionRegistry;

And then using injcted SessionRegistry you can access the list of all principals:

List<Object> principals = sessionRegistry.getAllPrincipals();

List<String> usersNamesList = new ArrayList<String>();

for (Object principal: principals) {
    if (principal instanceof User) {
        usersNamesList.add(((User) principal).getUsername());
    }
}

But before injecting session registry you need to define session management part in your spring-security.xml (look at Session Management section in Spring Security reference documentation) and in concurrency-control section you should set alias for session registry object (session-registry-alias) by which you will inject it.

    <security:http access-denied-page="/error403.jsp" use-expressions="true" auto-config="false">
        <security:session-management session-fixation-protection="migrateSession" session-authentication-error-url="/login.jsp?authFailed=true"> 
            <security:concurrency-control max-sessions="1" error-if-maximum-exceeded="true" expired-url="/login.html" session-registry-alias="sessionRegistry"/>
        </security:session-management>

    ...
    </security:http>

Answer 2

You need to inject SessionRegistry (as mentioned eariler) and then you can do it in one pipeline like this:

public List<UserDetails> findAllLoggedInUsers() {
    return sessionRegistry.getAllPrincipals()
            .stream()
            .filter(principal -> principal instanceof UserDetails)
            .map(UserDetails.class::cast)
            .collect(Collectors.toList());
}

Answer 3

In JavaConfig, it would look like this:

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {
    @Override
    protected void configure(final HttpSecurity http) throws Exception {
        // ...
        http.sessionManagement().maximumSessions(1).sessionRegistry(sessionRegistry());
    }

    @Bean
    public SessionRegistry sessionRegistry() {
        return new SessionRegistryImpl();
    }

    @Bean
    public ServletListenerRegistrationBean<HttpSessionEventPublisher> httpSessionEventPublisher() {
        return new ServletListenerRegistrationBean<HttpSessionEventPublisher>(new HttpSessionEventPublisher());
    }
}

With the calling code looking like this:

public class UserController {
    @Autowired
    private SessionRegistry sessionRegistry;

    public void listLoggedInUsers() {
        final List<Object> allPrincipals = sessionRegistry.getAllPrincipals();

        for(final Object principal : allPrincipals) {
            if(principal instanceof SecurityUser) {
                final SecurityUser user = (SecurityUser) principal;

                // Do something with user
                System.out.println(user);
            }
        }
    }
}

Note that SecurityUser is my own class which implements UserDetails.

Answer 4

Found this note to be quite important and relevant:

"[21] Authentication by mechanisms which perform a redirect after authenticating (such as form-login) will not be detected by SessionManagementFilter, as the filter will not be invoked during the authenticating request. Session-management functionality has to be handled separately in these cases."

https://docs.spring.io/spring-security/site/docs/3.1.x/reference/session-mgmt.html#d0e4399

Also, apparently a lot of people have troubles getting sessionRegistry.getAllPrincipals() returning something different from an empty array. In my case, I fixed it by adding the sessionAuthenticationStrategy to my custom authenticationFilter:

@Bean
public CustomUsernamePasswordAuthenticationFilter authenticationFilter() throws Exception {
...

  authenticationFilter.setSessionAuthenticationStrategy(sessionAuthenticationStrategy());
}

@Bean
public SessionRegistry sessionRegistry() {
    return new SessionRegistryImpl();
}

//cf. https://stackoverflow.com/questions/32463022/sessionregistry-is-empty-when-i-use-concurrentsessioncontrolauthenticationstrate
public SessionAuthenticationStrategy sessionAuthenticationStrategy() {
    List<SessionAuthenticationStrategy> stratList = new ArrayList<>();
    SessionFixationProtectionStrategy concStrat = new SessionFixationProtectionStrategy();
    stratList.add(concStrat);
    RegisterSessionAuthenticationStrategy regStrat = new RegisterSessionAuthenticationStrategy(sessionRegistry());
    stratList.add(regStrat);
    CompositeSessionAuthenticationStrategy compStrat = new CompositeSessionAuthenticationStrategy(stratList);
    return compStrat;
}

Answer 5

Please correct me if I'm wrong too.

I think @Adam's and @elysch`s answer is incomplete. I noticed that there are needed to add listener:

 servletContext.addListener(HttpSessionEventPublisher.class);

to

public class AppInitializer implements WebApplicationInitializer {

@Override
public void onStartup(ServletContext servletContext) {
  ...
servletContext.addListener(HttpSessionEventPublisher.class);
}

with security conf:

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {
    @Override
    protected void configure(final HttpSecurity http) throws Exception {
        // ...
        http.sessionManagement().maximumSessions(1).sessionRegistry(sessionRegistry());
    }

    @Bean
    public SessionRegistry sessionRegistry() {
        return new SessionRegistryImpl();
    }

    @Bean
    public HttpSessionEventPublisher httpSessionEventPublisher() {
        return new HttpSessionEventPublisher();
    }
}

And then you will get current online users!

Answer 6

Please correct me if I'm wrong.

I think @Adam's answer is incomplete. I noticed that sessions already expired in the list were appearing again.

public class UserController {
    @Autowired
    private SessionRegistry sessionRegistry;

    public void listLoggedInUsers() {
        final List<Object> allPrincipals = sessionRegistry.getAllPrincipals();

        for (final Object principal : allPrincipals) {
            if (principal instanceof SecurityUser) {
                final SecurityUser user = (SecurityUser) principal;

                List<SessionInformation> activeUserSessions =
                        sessionRegistry.getAllSessions(principal,
                                /* includeExpiredSessions */ false); // Should not return null;

                if (!activeUserSessions.isEmpty()) {
                    // Do something with user
                    System.out.println(user);
                }
            }
        }
    }
}

Hope it helps.