Shiro logout 302重定向，shiro 302解决方案

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©Copyright 蕃薯耀 2022-04-09

https://www.cnblogs.com/fanshuyao/

一、问题描述

当登录退出为Ajax请求时，使用Shiro的logout退出登录，会发生302重定向，导致不能正常退出。

二、解决方案

1、重写LogoutFilter 过滤器

 
import java.util.Locale;
 
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import org.apache.shiro.session.SessionException;
import org.apache.shiro.subject.Subject;
import org.apache.shiro.web.filter.authc.LogoutFilter;
import org.apache.shiro.web.util.WebUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
 
import com.lqy.shiro.bean.Result;
import com.lqy.shiro.utils.RequestUtils;
 
/**
 * 重写shiro logout逻辑，避免是Ajax请求发生302重定向问题
 * @author islee
 *
 */
public class ShiroLogoutFilter extends LogoutFilter {
 
    private static final Logger log = LoggerFactory.getLogger(ShiroLogoutFilter.class);
    
    @Override
    protected boolean preHandle(ServletRequest request, ServletResponse response) throws Exception {
 
        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponse res = (HttpServletResponse) response;
        
        Subject subject = getSubject(request, response);
 
        // Check if POST only logout is enabled
        if (isPostOnlyLogout()) {
 
            // check if the current request's method is a POST, if not redirect
            if (!WebUtils.toHttp(request).getMethod().toUpperCase(Locale.ENGLISH).equals("POST")) {
               return onLogoutRequestNotAPost(request, response);
            }
        }
 
        String redirectUrl = getRedirectUrl(request, response, subject);
        
        try {
            subject.logout();
            
        } catch (SessionException ise) {
            
            log.debug("Encountered session exception during logout.  This can generally safely be ignored.", ise);
        }
        
        if(RequestUtils.isAjaxOrJsonRequest(req)) {
            RequestUtils.write(res, Result.ok("退出登录"));
            
        }else {
            issueRedirect(request, response, redirectUrl);
        }
        
        return false;
    }
    
}

核心代码是：

if(RequestUtils.isAjaxOrJsonRequest(req)) {
    RequestUtils.write(res, Result.ok("退出登录"));
            
}else {
    issueRedirect(request, response, redirectUrl);
}

判断是否为Ajax请求或者是Json请求，如果是，返回json字符串，否则默认进行登录跳转，即302重定向。

2、配置LogoutFilter 过滤器（ShiroLogoutFilter）

    @Bean
    public ShiroFilterFactoryBean shiroFilterFactoryBean () {
        ShiroFilterFactoryBean shiroFilterFactoryBean = new ShiroFilterFactoryBean();
        
        
        //自定义过滤器
        LinkedHashMap<String, Filter> filtsMap=new LinkedHashMap<String, Filter>();
        filtsMap.put("logout",new ShiroLogoutFilter() );
        
        shiroFilterFactoryBean.setFilters(filtsMap);
        
        
        return shiroFilterFactoryBean;
    }

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