Custom Authentication Entrypoint not being called on failed Authentication - spring-boot

Question

I have setup an OAUTH Authorization server that's supposed to allow clients request for tokens. It's also supposed to allow admin users carry out other operations.
In my Web Security Configuration:
#Configuration
#EnableWebSecurity
public class ApiSecurityConfig extends WebSecurityConfigurerAdapter {
private #Autowired CustomAuthenticationProvider authenticationProvider;
private #Autowired CustomAuthenticationEntryPoint entryPoint;
#Override
#Bean
protected AuthenticationManager authenticationManager() throws Exception {
return super.authenticationManager();
}
#Override
protected void configure(HttpSecurity http) throws Exception {
http.csrf().disable().httpBasic().and().cors().and()
.authorizeRequests()
.antMatchers(HttpMethod.OPTIONS, "/oauth/token").permitAll()
.anyRequest()
.authenticated()
.and()
.exceptionHandling()
.authenticationEntryPoint(entryPoint)
.defaultAuthenticationEntryPointFor(entryPoint, new AntPathRequestMatcher("/api/v1/**"));
}
#Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception {
auth.authenticationProvider(authenticationProvider);
}
}
Ideally, when an admin user tries to call any endpoint under "/api/v1/**", they should be authenticated - and in fact, they are.
The issue now is, when authentication fails, the authentication entry endpoint is ignored. I don't understand why this is.
I even included the "default authentication entry point for" just to see if that would help, but it didn't.
Please, how do I resolve this?

Answer 1

After playing around with the http security configuration, I took inspiration from this article (https://www.baeldung.com/spring-security-basic-authentication) and changed it to:
#Override
protected void configure(HttpSecurity http) throws Exception {
http.csrf().disable().cors().and()
.authorizeRequests()
.antMatchers(HttpMethod.OPTIONS, "/oauth/token").permitAll()
.anyRequest().authenticated()
.and()
.httpBasic().authenticationEntryPoint(entryPoint);
}
Honestly, I don't know why what I had before wasn't working. Plenty of people have posted that as the solution to problems about entry end points. But I guess maybe something has changed in Spring that I'm not aware of.