如何在reactive Spring中强制进行身份验证？

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-security</artifactId>
</dependency>

@Configuration
@EnableWebFluxSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
            .authorizeExchange()
                .pathMatchers("/admin/**").hasRole("ADMIN")
                .anyExchange().authenticated()
                .and()
            .httpBasic()
                .and()
            .formLogin();
    }
}

@Configuration
@EnableWebFluxSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        // ...
    }

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth
            .inMemoryAuthentication()
                .withUser("user")
                    .password("{noop}password")
                    .roles("USER")
                .and()
                .withUser("admin")
                    .password("{noop}password")
                    .roles("ADMIN");
    }
}