SpringBoot Mongo HttpSession：如何结合SpringHttpSessionConfiguration自定义SessionRepositoryFilter？

1. 自定义SessionRepositoryFilter，添加时间判断逻辑 #

继承SessionRepositoryFilter，重写核心方法，在会话提交前判断距离上次持久化是否超过5分钟，仅满足条件时才执行Mongo写入操作：

import org.springframework.session.Session;
import org.springframework.session.SessionRepository;
import org.springframework.session.web.http.SessionRepositoryFilter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.time.Duration;
import java.time.Instant;

public class LazySaveMongoSessionRepositoryFilter<S extends Session> extends SessionRepositoryFilter<S> {

    private static final Duration SAVE_INTERVAL = Duration.ofMinutes(5);

    public LazySaveMongoSessionRepositoryFilter(SessionRepository<S> sessionRepository) {
        super(sessionRepository);
    }

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
        super.doFilterInternal(request, response, () -> {
            try {
                S session = getSession(request);
                if (session != null) {
                    Instant lastSaveTime = getLastSaveTime(session);
                    Instant now = Instant.now();
                    // 新会话或距离上次保存超过5分钟时，执行持久化
                    if (lastSaveTime == null || Duration.between(lastSaveTime, now).compareTo(SAVE_INTERVAL) > 0) {
                        session.setLastAccessedTime(now);
                        getSessionRepository().save(session);
                        session.setAttribute("LAST_SAVE_TIMESTAMP", now);
                    } else {
                        // 仅更新内存中的最后访问时间，不写入Mongo
                        session.setLastAccessedTime(now);
                    }
                }
                filterChain.doFilter(request, response);
            } catch (IOException | ServletException e) {
                throw new RuntimeException(e);
            }
        });
    }

    @SuppressWarnings("unchecked")
    private Instant getLastSaveTime(S session) {
        return (Instant) session.getAttribute("LAST_SAVE_TIMESTAMP");
    }
}

2. 覆盖SpringHttpSessionConfiguration的过滤器Bean #

创建配置类继承SpringHttpSessionConfiguration，替换默认的过滤器为自定义实现：

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.session.SessionRepository;
import org.springframework.session.config.annotation.web.http.SpringHttpSessionConfiguration;

@Configuration
public class CustomHttpSessionConfiguration extends SpringHttpSessionConfiguration {

    @Override
    @Bean
    public <S extends org.springframework.session.Session> SessionRepositoryFilter<S> sessionRepositoryFilter(SessionRepository<S> sessionRepository) {
        return new LazySaveMongoSessionRepositoryFilter<>(sessionRepository);
    }
}

3. 关键说明 #

• 会话的30分钟过期时间不受影响，Mongo的TTL索引会正常清理过期会话；
• 若会话中有业务属性变更（如用户登录状态修改），需手动调用sessionRepository.save(session)确保变更及时持久化；
• 新会话会立即执行第一次持久化，后续仅每隔5分钟触发一次写入操作。

内容的提问来源于stack exchange，提问作者SOUser2009 Geeky