How to send specific response in intercept-url? - spring-security

Question

I am new to spring. We are building a Mobile-app for our client. The mobile-app will interact with our rest services. But initially, the user should login to the mobile app and then will be able to access the other services.
I have built a Login service which will validate the user credentials with ldap and create the session and the subsequent requests to other services could be consumed.
But if the services are requested anonymously, a specific response object need to be returned.
Currently with below configuration, I am able to return the response code 403.
<beans:bean id="preAuthenticatedProcessingFilterEntryPoint"
class="org.springframework.security.web.authentication.Http403ForbiddenEntryPoint" />
<security:http use-expressions="true" entry-point-ref="preAuthenticatedProcessingFilterEntryPoint">
<security:intercept-url pattern="/scheduling/**" access="isAuthenticated()" />
</security:http>
But what would be required to respond with a error message in the response body.
I tried to implement the re-direct url, in EntryPoints. But I am not comfortable as the request should not be redirected.
I have a default error Response, which I would need to implement if the anonymous user tries to access services
<ErrorInfo>
<message>Access Denied</message>
<status>403</status>
<url>requested URL</url>
</ErrorInfo>

Answer 1

If I get it right, you want to adjust the response that is currently returned in case of unauthenticated access. In such case you need to implement and register your own AuthenticationEntryPoint or extend Http403ForbiddenEntryPoint you are currently using and override commence method to return response containing also required body.
<beans:bean id="yourCustomEntryPoint" class="com.example.YourCustomEntryPoint" />
<security:http use-expressions="true" entry-point-ref="yourCustomEntryPoint">
<security:intercept-url pattern="/scheduling/**" access="isAuthenticated()" />
</security:http>