如何在Spring中获取Session对象？

Question

我对Spring和Spring安全性比较陌生.

我试图编写一个程序,我需要使用Spring安全性在服务器端验证用户,

我想出了以下内容:

public class CustomAuthenticationProvider extends AbstractUserDetailsAuthenticationProvider{
    @Override
    protected void additionalAuthenticationChecks(UserDetails userDetails, UsernamePasswordAuthenticationToken usernamePasswordAuthenticationToken)
                    throws AuthenticationException
    {
        System.out.println("Method invoked : additionalAuthenticationChecks isAuthenticated ? :"+usernamePasswordAuthenticationToken.isAuthenticated());
    }

    @Override
    protected UserDetails retrieveUser(String username,UsernamePasswordAuthenticationToken authentication) throws AuthenticationException 
    {
        System.out.println("Method invoked : retrieveUser");
        //so far so good, i can authenticate user here, and throw exception if not authenticated!!
        //THIS IS WHERE I WANT TO ACCESS SESSION OBJECT
    }
}

我的用例是,当用户通过身份验证时,我需要放置一个属性,如:

session.setAttribute("userObject", myUserObject);

myUserObject是某个类的对象,我可以跨多个用户请求访问整个服务器代码.

Answer 1

你的朋友在这里 org.springframework.web.context.request.RequestContextHolder

// example usage
public static HttpSession session() {
    ServletRequestAttributes attr = (ServletRequestAttributes) RequestContextHolder.currentRequestAttributes();
    return attr.getRequest().getSession(true); // true == allow create
}

这将由标准的spring mvc dispatch servlet填充,但如果您使用的是另一个Web框架,则需要org.springframework.web.filter.RequestContextFilter在web.xml管理持有者时添加一个过滤器.

编辑:作为一个侧面问题,你实际上想要做什么,我不确定你应该需要访问HttpSession的retieveUser方法UserDetailsService.Spring安全性会将UserDetails对象放在会话中.可以通过访问以下内容来检索它SecurityContextHolder:

public static UserDetails currentUserDetails(){
    SecurityContext securityContext = SecurityContextHolder.getContext();
    Authentication authentication = securityContext.getAuthentication();
    if (authentication != null) {
        Object principal = authentication.getPrincipal();
        return principal instanceof UserDetails ? (UserDetails) principal : null;
    }
    return null;
}

Answer 2

既然你正在使用Spring,坚持使用Spring,不要像其他帖子那样自己破解它.

在春季手册说:

出于安全目的,您不应直接与HttpSession交互.没有理由这样做 - 总是使用SecurityContextHolder.

建议的访问会话的最佳做法是:

Object principal = SecurityContextHolder.getContext().getAuthentication().getPrincipal();

if (principal instanceof UserDetails) {
  String username = ((UserDetails)principal).getUsername();
} else {
  String username = principal.toString();
}

这里的关键是Spring和Spring Security为Session Fixation Prevention做了各种各样的好事.这些事情假设您正在使用Spring框架,因为它被设计为使用.因此,在您的servlet中,使其具有上下文感知能力,并像上面的示例一样访问会话.

如果您只需要在会话范围中存储一些数据,请尝试创建一些像这个示例的会话范围bean ,让autowire发挥其魔力.:)

Answer 3

我制作了自己的实用程序。它很方便。:)

package samples.utils;

import java.util.Arrays;
import java.util.Collection;
import java.util.Locale;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import javax.sql.DataSource;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.MessageSource;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.ui.context.Theme;
import org.springframework.util.ClassUtils;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.ThemeResolver;
import org.springframework.web.servlet.support.RequestContextUtils;


/**
 * SpringMVC????
 * 
 * @author ??(yingzhor@gmail.com)
 *
 */
public final class WebContextHolder {

    private static final Logger LOGGER = LoggerFactory.getLogger(WebContextHolder.class);

    private static WebContextHolder INSTANCE = new WebContextHolder();

    public WebContextHolder get() {
        return INSTANCE;
    }

    private WebContextHolder() {
        super();
    }

    // --------------------------------------------------------------------------------------------------------------

    public HttpServletRequest getRequest() {
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.currentRequestAttributes();
        return attributes.getRequest();
    }

    public HttpSession getSession() {
        return getSession(true);
    }

    public HttpSession getSession(boolean create) {
        return getRequest().getSession(create);
    }

    public String getSessionId() {
        return getSession().getId();
    }

    public ServletContext getServletContext() {
        return getSession().getServletContext();    // servlet2.3
    }

    public Locale getLocale() {
        return RequestContextUtils.getLocale(getRequest());
    }

    public Theme getTheme() {
        return RequestContextUtils.getTheme(getRequest());
    }

    public ApplicationContext getApplicationContext() {
        return WebApplicationContextUtils.getWebApplicationContext(getServletContext());
    }

    public ApplicationEventPublisher getApplicationEventPublisher() {
        return (ApplicationEventPublisher) getApplicationContext();
    }

    public LocaleResolver getLocaleResolver() {
        return RequestContextUtils.getLocaleResolver(getRequest());
    }

    public ThemeResolver getThemeResolver() {
        return RequestContextUtils.getThemeResolver(getRequest());
    }

    public ResourceLoader getResourceLoader() {
        return (ResourceLoader) getApplicationContext();
    }

    public ResourcePatternResolver getResourcePatternResolver() {
        return (ResourcePatternResolver) getApplicationContext();
    }

    public MessageSource getMessageSource() {
        return (MessageSource) getApplicationContext();
    }

    public ConversionService getConversionService() {
        return getBeanFromApplicationContext(ConversionService.class);
    }

    public DataSource getDataSource() {
        return getBeanFromApplicationContext(DataSource.class);
    }

    public Collection<String> getActiveProfiles() {
        return Arrays.asList(getApplicationContext().getEnvironment().getActiveProfiles());
    }

    public ClassLoader getBeanClassLoader() {
        return ClassUtils.getDefaultClassLoader();
    }

    private <T> T getBeanFromApplicationContext(Class<T> requiredType) {
        try {
            return getApplicationContext().getBean(requiredType);
        } catch (NoUniqueBeanDefinitionException e) {
            LOGGER.error(e.getMessage(), e);
            throw e;
        } catch (NoSuchBeanDefinitionException e) {
            LOGGER.warn(e.getMessage());
            return null;
        }
    }

}