[[jc-logout]]
= Handling Logouts

[[logout-java-configuration]]
== Logout Java/Kotlin Configuration

When using the `{security-api-url}org/springframework/security/config/annotation/web/configuration/WebSecurityConfigurerAdapter.html[WebSecurityConfigurerAdapter]`, logout capabilities are automatically applied.
The default is that accessing the URL `/logout` will log the user out by:

- Invalidating the HTTP Session
- Cleaning up any RememberMe authentication that was configured
- Clearing the `SecurityContextHolder`
- Redirect to `/login?logout`

Similar to configuring login capabilities, however, you also have various options to further customize your logout requirements:

.Logout Configuration
====
.Java
[source,java,role="primary"]
----
protected void configure(HttpSecurity http) throws Exception {
    http
        .logout(logout -> logout                                                // <1>
            .logoutUrl("/my/logout")                                            // <2>
            .logoutSuccessUrl("/my/index")                                      // <3>
            .logoutSuccessHandler(logoutSuccessHandler)                         // <4>
            .invalidateHttpSession(true)                                        // <5>
            .addLogoutHandler(logoutHandler)                                    // <6>
            .deleteCookies(cookieNamesToClear)                                  // <7>
        )
        ...
}
----

.Kotlin
[source,kotlin,role="secondary"]
-----
override fun configure(http: HttpSecurity) {
    http {
        logout {
            logoutUrl = "/my/logout"                              // <1>
            logoutSuccessUrl = "/my/index"                        // <2>
            logoutSuccessHandler = customLogoutSuccessHandler     // <3>
            invalidateHttpSession = true                          // <4>
            addLogoutHandler(logoutHandler)                       // <5>
            deleteCookies(cookieNamesToClear)                     // <6>
        }
    }
}
-----
====

<1> Provides logout support.
This is automatically applied when using `WebSecurityConfigurerAdapter`.
<2> The URL that triggers log out to occur (default is `/logout`).
If CSRF protection is enabled (default), then the request must also be a POST.
For more information, please consult the {security-api-url}org/springframework/security/config/annotation/web/configurers/LogoutConfigurer.html#logoutUrl-java.lang.String-[Javadoc].
<3> The URL to redirect to after logout has occurred.
The default is `/login?logout`.
For more information, please consult the {security-api-url}org/springframework/security/config/annotation/web/configurers/LogoutConfigurer.html#logoutSuccessUrl-java.lang.String-[Javadoc].
<4> Let's you specify a custom `LogoutSuccessHandler`.
If this is specified, `logoutSuccessUrl()` is ignored.
For more information, please consult the {security-api-url}org/springframework/security/config/annotation/web/configurers/LogoutConfigurer.html#logoutSuccessHandler-org.springframework.security.web.authentication.logout.LogoutSuccessHandler-[Javadoc].
<5> Specify whether to invalidate the `HttpSession` at the time of logout.
This is *true* by default.
Configures the `SecurityContextLogoutHandler` under the covers.
For more information, please consult the {security-api-url}org/springframework/security/config/annotation/web/configurers/LogoutConfigurer.html#invalidateHttpSession-boolean-[Javadoc].
<6> Adds a `LogoutHandler`.
`SecurityContextLogoutHandler` is added as the last `LogoutHandler` by default.
<7> Allows specifying the names of cookies to be removed on logout success.
This is a shortcut for adding a `CookieClearingLogoutHandler` explicitly.

[NOTE]
====
Logouts can of course also be configured using the XML Namespace notation.
Please see the documentation for the xref:servlet/appendix/namespace.adoc#nsa-logout[ logout element] in the Spring Security XML Namespace section for further details.
====

Generally, in order to customize logout functionality, you can add
`{security-api-url}org/springframework/security/web/authentication/logout/LogoutHandler.html[LogoutHandler]`
and/or
`{security-api-url}org/springframework/security/web/authentication/logout/LogoutSuccessHandler.html[LogoutSuccessHandler]`
implementations.
For many common scenarios, these handlers are applied under the
covers when using the fluent API.

[[ns-logout]]
== Logout XML Configuration
The `logout` element adds support for logging out by navigating to a particular URL.
The default logout URL is `/logout`, but you can set it to something else using the `logout-url` attribute.
More information on other available attributes may be found in the namespace appendix.

[[jc-logout-handler]]
== LogoutHandler

Generally, `{security-api-url}org/springframework/security/web/authentication/logout/LogoutHandler.html[LogoutHandler]`
implementations indicate classes that are able to participate in logout handling.
They are expected to be invoked to perform necessary clean-up.
As such they should
not throw exceptions.
Various implementations are provided:

- {security-api-url}org/springframework/security/web/authentication/rememberme/PersistentTokenBasedRememberMeServices.html[PersistentTokenBasedRememberMeServices]
- {security-api-url}org/springframework/security/web/authentication/rememberme/TokenBasedRememberMeServices.html[TokenBasedRememberMeServices]
- {security-api-url}org/springframework/security/web/authentication/logout/CookieClearingLogoutHandler.html[CookieClearingLogoutHandler]
- {security-api-url}org/springframework/security/web/csrf/CsrfLogoutHandler.html[CsrfLogoutHandler]
- {security-api-url}org/springframework/security/web/authentication/logout/SecurityContextLogoutHandler.html[SecurityContextLogoutHandler]
- {security-api-url}org/springframework/security/web/authentication/logout/HeaderWriterLogoutHandler.html[HeaderWriterLogoutHandler]

Please see xref:servlet/authentication/rememberme.adoc#remember-me-impls[Remember-Me Interfaces and Implementations] for details.

Instead of providing `LogoutHandler` implementations directly, the fluent API also provides shortcuts that provide the respective `LogoutHandler` implementations under the covers.
E.g. `deleteCookies()` allows specifying the names of one or more cookies to be removed on logout success.
This is a shortcut compared to adding a `CookieClearingLogoutHandler`.

[[jc-logout-success-handler]]
== LogoutSuccessHandler

The `LogoutSuccessHandler` is called after a successful logout by the `LogoutFilter`, to handle e.g.
redirection or forwarding to the appropriate destination.
Note that the interface is almost the same as the `LogoutHandler` but may raise an exception.

The following implementations are provided:

- {security-api-url}org/springframework/security/web/authentication/logout/SimpleUrlLogoutSuccessHandler.html[SimpleUrlLogoutSuccessHandler]
- HttpStatusReturningLogoutSuccessHandler

As mentioned above, you don't need to specify the `SimpleUrlLogoutSuccessHandler` directly.
Instead, the fluent API provides a shortcut by setting the `logoutSuccessUrl()`.
This will setup the `SimpleUrlLogoutSuccessHandler` under the covers.
The provided URL will be redirected to after a logout has occurred.
The default is `/login?logout`.

The `HttpStatusReturningLogoutSuccessHandler` can be interesting in REST API type scenarios.
Instead of redirecting to a URL upon the successful logout, this `LogoutSuccessHandler` allows you to provide a plain HTTP status code to be returned.
If not configured a status code 200 will be returned by default.

[[jc-logout-references]]
== Further Logout-Related References

- <<ns-logout, Logout Handling>>
- xref:servlet/test/mockmvc.adoc#test-logout[ Testing Logout]
- xref:servlet/integrations/servlet-api.adoc#servletapi-logout[ HttpServletRequest.logout()]
- xref:servlet/authentication/rememberme.adoc#remember-me-impls[Remember-Me Interfaces and Implementations]
- xref:servlet/exploits/csrf.adoc#servlet-considerations-csrf-logout[ Logging Out] in section CSRF Caveats
- Section xref:servlet/authentication/cas.adoc#cas-singlelogout[ Single Logout] (CAS protocol)
- Documentation for the xref:servlet/appendix/namespace.adoc#nsa-logout[ logout element] in the Spring Security XML Namespace section
