apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/spi/configuration/AuthConfiguration.java/SpringSecurityAuthAutoConfiguration/springSecurityUserService
class SpringSecurityAuthAutoConfiguration:    @Bean
    @ConditionalOnMissingBean(UserService.class)
    public UserService springSecurityUserService(PasswordEncoder passwordEncoder,
        JdbcUserDetailsManager userDetailsManager,
        UserRepository userRepository) {
      return new SpringSecurityUserService(passwordEncoder, userDetailsManager, userRepository);
    }