SpringCacheBasedUserCache为空

Question

我有使用spring boot、spring security和spring data的web应用程序。它是无国籍的。

我想避免总是调用db进行用户访问。所以我想使用SpringCacheBasedUserCache。

@Configuration
@EnableCaching
public class CacheConfig {

    @Bean
    CacheManager cacheManager() {
        SimpleCacheManager cacheManager = new SimpleCacheManager();
        cacheManager.setCaches(Arrays.asList(new ConcurrentMapCache("city"), new ConcurrentMapCache("userCache")));
        return cacheManager;
    }

    @Bean
    public UserCache userCache() throws Exception {

        Cache cache = (Cache) cacheManager().getCache("userCache");
        return new SpringCacheBasedUserCache(cache);
    }
}


@EnableCaching
@Configuration
@EnableWebSecurity
public class ApplicationSecurity extends WebSecurityConfigurerAdapter {
    @Bean
    public PasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder();
    }

    @Override
    public UserDetailsService userDetailsServiceBean() throws Exception {
        return new UserServiceImpl(commerceReposiotry, repository, defaultConfigRepository);
    }
    ...
}

我有一个类谁实现用户细节和另一个谁实现用户细节服务

@Service
public class UserServiceImpl implements UserDetailsService, UserService {

    private final CommerceRepository commerceReposiotry;
    private final UserAppRepository repository;
    private final DefaultConfigRepository defaultConfigRepository;

    @Autowired
    private UserCache userCache;

    @Autowired
    private PasswordEncoder passwordEncoder;

    @Autowired
    public UserServiceImpl(final CommerceRepository commerceReposiotry, final UserAppRepository repository, final DefaultConfigRepository defaultConfigRepository) {
        this.commerceReposiotry = commerceReposiotry;
        this.repository = repository;
        this.defaultConfigRepository = defaultConfigRepository;
    }


    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {

        UserDetails user = userCache.getUserFromCache(username);
        UserApp userapp = null;

        if (user == null) {
            userapp = repository.findByUsername(username);
        }

        if (userapp == null) {
            throw new UsernameNotFoundException("Username " + username + " not found");
        }

        userCache.putUserInCache(user);

        return new CustomUserDetails(userapp);
    }
    ...
}

在loadUserByUsername方法中，userCache为空

Answer 1

要么将@Bean放在userDemailsServiceBean方法上，要么（如建议的那样）完全从UserDemailsService中删除缓存，并将其包装在CachingUserDemailsService中，而不是简单地覆盖userDemailsService方法。

@Configuration
@EnableWebSecurity
public class ApplicationSecurity extends WebSecurityConfigurerAdapter {

    @Autowired
    private UserCache userCache;

    @Bean
    public PasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder();
    }

    @Override
    public UserDetailsService userDetailsService() throws Exception {

        UserServiceImpl userService = new UserServiceImpl(commerceReposiotry, repository, defaultConfigRepository);
        CachingUserDetailsService cachingUserService = new CachingUserDetailsService(userService);
        cachingUserService.setUserCache(this.userCache);
        return cachingUserService;
    }
    ...
}

您的其他配置上已经有@EnableCache，因此无需再次拥有它。只需将缓存注入配置类并构造一个CachingUserDemailsService，它委托给您的UserDemailsService来检索用户。

当然，您必须从您自己的UserDemailsService中删除缓存，现在可以专注于用户管理/检索，而不是与缓存混合。

Edit(1):构造函数不是公共的，这使得创建bean更加困难。这可以通过使用< code>BeanUtils和< code>ClassUtils来实现。用下面的代码替换对< code>new的调用应该会创建一个实例。

private UserDetailsService cachingUserDetailsService(UserDetailsService delegate) {
    Constructor<CachingUserDetailsService> ctor = ClassUtils.getConstructorIfAvailable(CachingUserDetailsService.class, UserDetailsService.class);
    return BeanUtils.instantiateClass(ctor, delegate);
}

编辑（2）：显然，我已经遇到过一次（大约2年前），并为其注册了此问题。