Spring mvc configuration to integrate with a custom SSO authentication - spring

Question

I'm failing to integrate an existing custom Single-sign-on service (for the authentication of my spring mvc application -aka. myApp-).
Once I map the spring DispatcherServlet to "/", myApp skips the authentication process against the SSO application, no matter if there's session or not.
Web.xml (Spring Configuration)
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/mvc-dispatcher-servlet.xml</param-value>
</context-param>
<!-- Spring MVC DispatcherServlet -->
<servlet>
<servlet-name>mvc-dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>mvc-dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
Here is the configuration that I need to integrate in myApp web.xml, to integrate the SSO authentication:
Web.xml (Custom SSO Configuration)
<filter>
<filter-name>SSOAuthenticationFilter</filter-name>
<filter-class>custom.sso.SSOAuthenticationFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>SSOAuthenticationFilter</filter-name>
<url-pattern>/WEB-INF/views/*</url-pattern>
</filter-mapping>
<!-- Context Params -->
<context-param>
<param-name>myAppId</param-name>
<param-value>65asd5a4sd65asd65a4sd65asd4</param-value>
</context-param>
<context-param>
<param-name>loginPath</param-name>
<param-value>login.jsp</param-value>
</context-param>
<context-param>
<param-name>ssoAppPath</param-name>
<param-value>http://localhost:8080/SSO_AuthenticationApp</param-value>
</context-param>
<!-- SSO Login Servlet -->
<servlet>
<servlet-name>SSOloginServlet</servlet-name>
<servlet-class>custom.sso.SSOLoginServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>SSOloginServlet</servlet-name>
<url-pattern>/login</url-pattern>
</servlet-mapping>
<!-- SSO properties (myAppId, ssoAppPath, loginPath) -->
<listener>
<listener-class>custom.sso.SSOPropertiesRetriever</listener-class>
</listener>
How can I configurate spring to let the SSO servlet to do the authentication process?
I was thinking if there's a way of declaring the customSSO servlet as a bean in the spring dispatcher-servlet-config.xml?
Or maybe implementing it in a #Controller?
(My hands are tied about the sso, I'm forced to use it for the authentication, cause myApp will be just another in a family of applications login through this custom sso... I would prefer to use spring security instead).
Thanks.
EDITED:
I finally opted for a migration to Spring Boot, seems way more clear to configure a project that way.

Answer 1

For the filter you can use a SpringFilter and implement the logic in a bean:
<filter>
<filter-name>springFilter</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
<init-param>
<param-name>targetBeanName</param-name>
<param-value>authenticationFilter</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>springFilter</filter-name>
<url-pattern>/some-url</url-pattern>
</filter-mapping>
For the servlet I guess you may have to change your mappings to something that looks like the following:
<servlet>
<servlet-name>loginServlet</servlet-name>
<servlet-class>my.package.LoginServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>loginServlet</servlet-name>
<url-pattern>/login</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>dispatcherServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/mvc-config.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>dispatcherServlet</servlet-name>
<url-pattern>/app/*</url-pattern>
</servlet-mapping>
Here I'm assuming that everything goes in the same WEB.xml file