SecurityUtils.getSubject().getPrincipal()为null的问题

SecurityUtils.getSubject().getPrincipal()为null的问题

目录

SecurityUtils.getSubject().getPrincipal()为null

解决办法

shiro SecurityUtils.getSubject()深度分析

SecurityUtils.getSubject().getPrincipal()为null

我在项目中获取getUserId(),和getUserName()获取不到值。

他们都是通过SecurityUtils.getSubject().getPrincipal()去获取的。

反复测试发现原因是 :在shiroConfig里面:

该方法,注意(是该接口名)被写为anon,不通过验证,即:

filterMap.put("/druid/**", “anon”);

这种写法是为了postman测试时不被拦截。

解决办法

从页面访问后端不需要anon了。

anon是不做拦截,authc是走自定义拦截

oauth2是自带拦截

修改为:

filterMap.put("/druid/**", “authc”); shiro SecurityUtils.getSubject()深度分析

1.总的来说,SecurityUtils.getSubject()是每个请求创建一个Subject, 并保存到ThreadContext的resources(ThreadLocal<Map<Object, Object>>)变量中,也就是一个http请求一个subject,并绑定到当前过程。 

问题来了:.subject.login()登陆认证成功后,下一次请求如何知道是那个用户的请求呢? 

友情提示:本文唯一可以读一下的就是分析这个疑问,如果你已经明白就不用往下看了。 

首先给出内部原理:1个请求1个Subject原理:由于ShiroFilterFactoryBean本质是个AbstractShiroFilter过滤器,所以每次请求都会执行doFilterInternal里面的createSubject方法。 

猜想:因为subject是绑定到当前线程,这肯定需要一个中介存储状态 

public static Subject getSubject() { Subject subject = ThreadContext.getSubject(); if (subject == null) { subject = (new Builder()).buildSubject(); ThreadContext.bind(subject); } return subject; } public abstract class ThreadContext { private static final Logger log = LoggerFactory.getLogger(ThreadContext.class); public static final String SECURITY_MANAGER_KEY = ThreadContext.class.getName() + "_SECURITY_MANAGER_KEY"; public static final String SUBJECT_KEY = ThreadContext.class.getName() + "_SUBJECT_KEY"; private static final ThreadLocal<Map<Object, Object>> resources = new ThreadContext.InheritableThreadLocalMap(); protected ThreadContext() { } public static Map<Object, Object> getResources() { return (Map)(resources.get() == null ? Collections.emptyMap() : new HashMap((Map)resources.get())); } public static void setResources(Map<Object, Object> newResources) { if (!CollectionUtils.isEmpty(newResources)) { ensureResourcesInitialized(); ((Map)resources.get()).clear(); ((Map)resources.get()).putAll(newResources); } } private static Object getValue(Object key) { Map<Object, Object> perThreadResources = (Map)resources.get(); return perThreadResources != null ? perThreadResources.get(key) : null; } private static void ensureResourcesInitialized() { if (resources.get() == null) { resources.set(new HashMap()); } } public static Object get(Object key) { if (log.isTraceEnabled()) { String msg = "get() - in thread [" + Thread.currentThread().getName() + "]"; log.trace(msg); } Object value = getValue(key); if (value != null && log.isTraceEnabled()) { String msg = "Retrieved value of type [" + value.getClass().getName() + "] for key [" + key + "] bound to thread [" + Thread.currentThread().getName() + "]"; log.trace(msg); } return value; } public static void put(Object key, Object value) { if (key == null) { throw new IllegalArgumentException("key cannot be null"); } else if (value == null) { remove(key); } else { ensureResourcesInitialized(); ((Map)resources.get()).put(key, value); if (log.isTraceEnabled()) { String msg = "Bound value of type [" + value.getClass().getName() + "] for key [" + key + "] to thread [" + Thread.currentThread().getName() + "]"; log.trace(msg); } } } public static Object remove(Object key) { Map<Object, Object> perThreadResources = (Map)resources.get(); Object value = perThreadResources != null ? perThreadResources.remove(key) : null; if (value != null && log.isTraceEnabled()) { String msg = "Removed value of type [" + value.getClass().getName() + "] for key [" + key + "]from thread [" + Thread.currentThread().getName() + "]"; log.trace(msg); } return value; } public static void remove() { resources.remove(); } public static SecurityManager getSecurityManager() { return (SecurityManager)get(SECURITY_MANAGER_KEY); } public static void bind(SecurityManager securityManager) { if (securityManager != null) { put(SECURITY_MANAGER_KEY, securityManager); } } public static SecurityManager unbindSecurityManager() { return (SecurityManager)remove(SECURITY_MANAGER_KEY); } public static Subject getSubject() { return (Subject)get(SUBJECT_KEY); } public static void bind(Subject subject) { if (subject != null) { put(SUBJECT_KEY, subject); } } public static Subject unbindSubject() { return (Subject)remove(SUBJECT_KEY); } private static final class InheritableThreadLocalMap<T extends Map<Object, Object>> extends InheritableThreadLocal<Map<Object, Object>> { private InheritableThreadLocalMap() { } protected Map<Object, Object> childValue(Map<Object, Object> parentValue) { return parentValue != null ? (Map)((HashMap)parentValue).clone() : null; } } }

subject登陆成功后,下一次请求如何知道是那个用户的请求呢? 

经过源码分析,核心实现如下DefaultSecurityManager类中: 

public Subject createSubject(SubjectContext subjectContext) { SubjectContext context = this.copy(subjectContext); context = this.ensureSecurityManager(context); context = this.resolveSession(context); context = this.resolvePrincipals(context); Subject subject = this.doCreateSubject(context); this.save(subject); return subject; }

每次请求都会重新设置Session和Principals,看到这里大概就能猜到:如果是web工程,直接从web容器获取httpSession,然后再从httpSession获取Principals,本质就是从cookie获取用户信息,然后每次都设置Principal,这样就知道是哪个用户的请求,并只得到这个用户有没有人认证成功,--本质:依赖于浏览器的cookie来维护session的 

扩展,如果不是web容器的app,如何实现实现无状态的会话 

1.一般的作法会在header中带有一个token,或者是在参数中,后台根据这个token来进行校验这个用户的身份,但是这个时候,servlet中的session就无法保存,我们在这个时候,就要实现自己的会话创建,普通的作法就是重写session与request的接口,然后在过滤器在把它替换成自己的request,所以得到的session也是自己的session,然后根据token来创建和维护会话 

2.shiro实现: 

重写shiro的sessionManage 

import org.apache.shiro.session.mgt.SessionKey; import org.apache.shiro.web.servlet.ShiroHttpServletRequest; import org.apache.shiro.web.session.mgt.DefaultWebSessionManager; import org.apache.shiro.web.util.WebUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.Serializable; import java.util.UUID; /** * @author zxj<br> * 时间 2017/11/8 15:55 * 说明 ... */ public class StatelessSessionManager extends DefaultWebSessionManager { /** * 这个是服务端要返回给客户端, */ public final static String TOKEN_NAME = "TOKEN"; /** * 这个是客户端请求给服务端带的header */ public final static String HEADER_TOKEN_NAME = "token"; public final static Logger LOG = LoggerFactory.getLogger(StatelessSessionManager.class); @Override public Serializable getSessionId(SessionKey key) { Serializable sessionId = key.getSessionId(); if(sessionId == null){ HttpServletRequest request = WebUtils.getHttpRequest(key); HttpServletResponse response = WebUtils.getHttpResponse(key); sessionId = this.getSessionId(request,response); } HttpServletRequest request = WebUtils.getHttpRequest(key); request.setAttribute(TOKEN_NAME,sessionId.toString()); return sessionId; } @Override protected Serializable getSessionId(ServletRequest servletRequest, ServletResponse servletResponse) { HttpServletRequest request = (HttpServletRequest) servletRequest; String token = request.getHeader(HEADER_TOKEN_NAME); if(token == null){ token = UUID.randomUUID().toString(); } //这段代码还没有去查看其作用,但是这是其父类中所拥有的代码,重写完后我复制了过来...开始 request.setAttribute(ShiroHttpServletRequest.REFERENCED_SESSION_ID_SOURCE, ShiroHttpServletRequest.COOKIE_SESSION_ID_SOURCE); request.setAttribute(ShiroHttpServletRequest.REFERENCED_SESSION_ID, token); request.setAttribute(ShiroHttpServletRequest.REFERENCED_SESSION_ID_IS_VALID, Boolean.TRUE); request.setAttribute(ShiroHttpServletRequest.SESSION_ID_URL_REWRITING_ENABLED, isSessionIdUrlRewritingEnabled()); //这段代码还没有去查看其作用,但是这是其父类中所拥有的代码,重写完后我复制了过来...结束 return token; } } @RequestMapping("/") public void login(@RequestParam("code")String code, HttpServletRequest request){ Map<String,Object> data = new HashMap<>(); if(SecurityUtils.getSubject().isAuthenticated()){         //这里代码着已经登陆成功,所以自然不用再次认证,直接从rquest中取出就行了, data.put(StatelessSessionManager.HEADER_TOKEN_NAME,getServerToken()); data.put(BIND,ShiroKit.getUser().getTel() != null); response(data); } LOG.info("授权码为:" + code); AuthorizationService authorizationService = authorizationFactory.getAuthorizationService(Constant.clientType); UserDetail authorization = authorizationService.authorization(code); Oauth2UserDetail userDetail = (Oauth2UserDetail) authorization; loginService.login(userDetail); User user = userService.saveUser(userDetail,Constant.clientType.toString()); ShiroKit.getSession().setAttribute(ShiroKit.USER_DETAIL_KEY,userDetail); ShiroKit.getSession().setAttribute(ShiroKit.USER_KEY,user); data.put(BIND,user.getTel() != null);     //这里的代码,必须放到login之执行,因为login后,才会创建session,才会得到最新的token咯 data.put(StatelessSessionManager.HEADER_TOKEN_NAME,getServerToken()); response(data); } } import org.apache.shiro.mgt.SecurityManager; import org.apache.shiro.realm.Realm; import org.apache.shiro.spring.LifecycleBeanPostProcessor; import org.apache.shiro.spring.web.ShiroFilterFactoryBean; import org.apache.shiro.web.mgt.DefaultWebSecurityManager; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import java.util.LinkedHashMap; import java.util.Map; /** * @author zxj<br> * 时间 2017/11/8 15:40 * 说明 ... */ @Configuration public class ShiroConfiguration { @Bean public LifecycleBeanPostProcessor lifecycleBeanPostProcessor(){ return new LifecycleBeanPostProcessor(); } /** * 此处注入一个realm * @param realm * @return */ @Bean public SecurityManager securityManager(Realm realm){ DefaultWebSecurityManager securityManager = new DefaultWebSecurityManager(); securityManager.setSessionManager(new StatelessSessionManager()); securityManager.setRealm(realm); return securityManager; } @Bean public ShiroFilterFactoryBean shiroFilterFactoryBean(SecurityManager securityManager){ ShiroFilterFactoryBean bean = new ShiroFilterFactoryBean(); bean.setSecurityManager(securityManager); Map<String,String> map = new LinkedHashMap<>(); map.put("/public/**","anon"); map.put("/login/**","anon"); map.put("/**","user"); bean.setFilterChainDefinitionMap(map); return bean; } }

以上为个人经验,希望能给大家一个参考,也希望大家多多支持易知道(ezd.cc)。 

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