cas服务端集群，网上资料很多，无非就是session共享，ticket共享。 但是session共享是必须的吗？或者能实现集群吗？

实践：

1. ticket共享，直接上代码

  1. package org.jasig.cas.ticket;
  2.  
  3. import java.util.Collection;
  4. import java.util.HashSet;
  5. import java.util.Set;
  6. import java.util.concurrent.TimeUnit;
  7.  
  8. import org.jasig.cas.ticket.registry.AbstractDistributedTicketRegistry;
  9. import org.springframework.beans.factory.DisposableBean;
  10. import org.springframework.beans.factory.annotation.Autowired;
  11. import org.springframework.data.redis.core.RedisTemplate;
  12. import org.springframework.data.redis.core.StringRedisTemplate;
  13. import org.springframework.stereotype.Component;
  14.  
  15. /**
  16.  * @author zlx
  17.  * @Description: redis管理ticket
  18.  * @date 2018年4月9日 下午3:28:12
  19.  */
  20. @Component("redisTicketRegistry")
  21. public class RedisTicketRegistry extends AbstractDistributedTicketRegistry implements DisposableBean {
  22.     /**管理ticket key,避免使用redis keys命令*/
  23.     private final String TICKET_KEY_MANAGER = "ticket_key_manager";
  24.     @Autowired
  25.     private RedisTemplate<String, Ticket> redisTemplate;
  26.     @Autowired
  27.     private StringRedisTemplate stringRedisTemplate;
  28.     //默认失效时间 /小时
  29.     private int timeout = 8;
  30.  
  31.     @Override
  32.     public void updateTicket(final Ticket ticket) {
  33.         logger.debug("Updating ticket {}", ticket);
  34.         try {
  35.             this.redisTemplate.boundValueOps(ticket.getId()).set(ticket);
  36.             this.redisTemplate.expire(ticket.getId(), timeout, TimeUnit.HOURS);
  37.         } catch (final Exception e) {
  38.             logger.error("Failed updating {}", ticket, e);
  39.         }
  40.     }
  41.  
  42.     @Override
  43.     public void addTicket(final Ticket ticket) {
  44.         logger.debug("Adding ticket {}", ticket);
  45.         try {
  46.             this.redisTemplate.boundValueOps(ticket.getId()).set(ticket);
  47.             this.redisTemplate.expire(ticket.getId(), timeout, TimeUnit.HOURS);
  48.             this.stringRedisTemplate.boundSetOps(TICKET_KEY_MANAGER).add(ticket.getId());
  49.         } catch (final Exception e) {
  50.             logger.error("Failed adding {}", ticket, e);
  51.         }
  52.     }
  53.  
  54.     @Override
  55.     public int deleteTicket(final String ticketId) {
  56.         int count = 0;
  57.         logger.debug("Deleting ticket {}", ticketId);
  58.         try {
  59.             this.redisTemplate.delete(ticketId);
  60.             this.stringRedisTemplate.boundSetOps(TICKET_KEY_MANAGER).remove(ticketId);
  61.             count++;
  62.         } catch (final Exception e) {
  63.             logger.error("Failed deleting {}", ticketId, e);
  64.         }
  65.         return count;
  66.     }
  67.  
  68.     @Override
  69.     public Ticket getTicket(final String ticketId) {
  70.         try {
  71.             final Ticket t = this.redisTemplate.boundValueOps(ticketId).get();
  72.             if (t != null) {
  73.                 return getProxiedTicketInstance(t);
  74.             }
  75.         } catch (final Exception e) {
  76.             logger.error("Failed fetching {} ", ticketId, e);
  77.         }
  78.         return null;
  79.     }
  80.  
  81.     @Override
  82.     public boolean deleteSingleTicket(String ticketId) {
  83.         logger.debug("Deleting Single Ticket {}", ticketId);
  84.         try {
  85.             this.redisTemplate.delete(ticketId);
  86.             this.stringRedisTemplate.boundSetOps(TICKET_KEY_MANAGER).remove(ticketId);
  87.             return true;
  88.         } catch (final Exception e) {
  89.             logger.error("Failed deleting {}", ticketId, e);
  90.         }
  91.         return false;
  92.     }
  93.  
  94.     @Override
  95.     public Collection<Ticket> getTickets() {
  96.         Set<Ticket> tickets = new HashSet<Ticket>();
  97.  
  98.         Set<String> keys = this.stringRedisTemplate.boundSetOps(TICKET_KEY_MANAGER).members();
  99.         for (String key : keys) {
  100.             Ticket ticket = this.redisTemplate.boundValueOps(key).get();
  101.             if (ticket == null) {
  102.                 this.stringRedisTemplate.boundSetOps(TICKET_KEY_MANAGER).remove(key);
  103.             } else {
  104.                 tickets.add(ticket);
  105.             }
  106.         }
  107.         return tickets;
  108.     }
  109.  
  110.     @Override
  111.     public void destroy() throws Exception {
  112.         // TODO Auto-generated method stub
  113.  
  114.     }
  115.  
  116.     @Override
  117.     protected boolean needsCallback() {
  118.         // TODO Auto-generated method stub
  119.         return false;
  120.     }
  121.  
  122. }

deployerConfigContext.xml中变更：

  1.     <!-- <alias name="defaultTicketRegistry" alias="ticketRegistry" /> -->
  2.     <alias name="redisTicketRegistry" alias="ticketRegistry" />

ticket共享配好后，发布代码。 测试发现有时候cas集群有效。有时候报错。错误如下：

  1. 2018-05-14 16:48:11,841 ERROR [org.jasig.cas.util.WebflowCipherExecutor] - <Unable to correctly extract the Initialization Vector or ciphertext.>
  2. org.apache.shiro.crypto.CryptoException: Unable to correctly extract the Initialization Vector or ciphertext.
  3.     at org.apache.shiro.crypto.JcaCipherService.decrypt(JcaCipherService.java:378) ~[shiro-core-1.2.6.jar:1.2.6]
  4.     at org.jasig.cas.util.BinaryCipherExecutor.decode(BinaryCipherExecutor.java:102) ~[cas-server-core-util-4.2.7.jar:4.2.7]
  5.     at org.jasig.cas.util.BinaryCipherExecutor.decode(BinaryCipherExecutor.java:1) ~[cas-server-core-util-4.2.7.jar:4.2.7]
  6.     at org.jasig.cas.web.flow.CasWebflowCipherBean.decrypt(CasWebflowCipherBean.java:44) ~[cas-server-webapp-support-4.2.7.jar:4.2.7]
  7.     at org.jasig.spring.webflow.plugin.EncryptedTranscoder.decode(EncryptedTranscoder.java:105) ~[spring-webflow-client-repo-1.0.0.jar:1.0.0]
  8.     at org.jasig.spring.webflow.plugin.ClientFlowExecutionRepository.getFlowExecution(ClientFlowExecutionRepository.java:90) ~[spring-webflow-client-repo-1.0.0.jar:1.0.0]
  9.     at org.springframework.webflow.executor.FlowExecutorImpl.resumeExecution(FlowExecutorImpl.java:168) ~[spring-webflow-2.4.2.RELEASE.jar:2.4.2.RELEASE]
  10.     at org.springframework.webflow.mvc.servlet.FlowHandlerAdapter.handle(FlowHandlerAdapter.java:228) ~[spring-webflow-2.4.2.RELEASE.jar:2.4.2.RELEASE]
  11.     at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:961) ~[spring-webmvc-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  12.     at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:895) ~[spring-webmvc-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  13.     at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:967) ~[spring-webmvc-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  14.     at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:869) ~[spring-webmvc-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  15.     at javax.servlet.http.HttpServlet.service(HttpServlet.java:648) ~[servlet-api.jar:?]
  16.     at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:843) ~[spring-webmvc-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  17.     at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) ~[servlet-api.jar:?]
  18.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) ~[catalina.jar:8.5.0]
  19.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.0]
  20.     at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-websocket.jar:8.5.0]
  21.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.0]
  22.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.0]
  23.     at org.apereo.cas.security.ResponseHeadersEnforcementFilter.doFilter(ResponseHeadersEnforcementFilter.java:238) ~[cas-server-security-filter-2.0.6.jar:2.0.6]
  24.     at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  25.     at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  26.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.0]
  27.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.0]
  28.     at org.apereo.cas.security.RequestParameterPolicyEnforcementFilter.doFilter(RequestParameterPolicyEnforcementFilter.java:261) ~[cas-server-security-filter-2.0.6.jar:2.0.6]
  29.     at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  30.     at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  31.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.0]
  32.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.0]
  33.     at org.jasig.inspektr.common.web.ClientInfoThreadLocalFilter.doFilter(ClientInfoThreadLocalFilter.java:62) ~[inspektr-common-1.3.GA.jar:1.3.GA]
  34.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.0]
  35.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.0]
  36.     at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:121) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  37.     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  38.     at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  39.     at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  40.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.0]
  41.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.0]
  42.     at org.springframework.session.web.http.SessionRepositoryFilter.doFilterInternal(SessionRepositoryFilter.java:164) ~[spring-session-1.2.2.RELEASE.jar:?]
  43.     at org.springframework.session.web.http.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:80) ~[spring-session-1.2.2.RELEASE.jar:?]
  44.     at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  45.     at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) ~[spring-web-4.2.8.RELEASE.jar:4.2.8.RELEASE]
  46.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) ~[catalina.jar:8.5.0]
  47.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) ~[catalina.jar:8.5.0]
  48.     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) ~[catalina.jar:8.5.0]
  49.     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:108) ~[catalina.jar:8.5.0]
  50.     at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:522) ~[catalina.jar:8.5.0]
  51.     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) ~[catalina.jar:8.5.0]
  52.     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) ~[catalina.jar:8.5.0]
  53.     at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620) ~[catalina.jar:8.5.0]
  54.     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) ~[catalina.jar:8.5.0]
  55.     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) ~[catalina.jar:8.5.0]
  56.     at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:1096) ~[tomcat-coyote.jar:8.5.0]
  57.     at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) ~[tomcat-coyote.jar:8.5.0]
  58.     at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:760) ~[tomcat-coyote.jar:8.5.0]
  59.     at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1480) ~[tomcat-coyote.jar:8.5.0]
  60.     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0_77]
  61.     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0_77]
  62.     at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-util.jar:8.5.0]
  63.     at java.lang.Thread.run(Thread.java:745) [?:1.8.0_77]
  64. Caused by: java.lang.NullPointerException
  65.     at java.lang.System.arraycopy(Native Method) ~[?:1.8.0_77]
  66.     at org.apache.shiro.crypto.JcaCipherService.decrypt(JcaCipherService.java:370) ~[shiro-core-1.2.6.jar:1.2.6]
  67.     ... 60 more

查资料都说要用tomcat redis session manager实现集群tomcat的session共享

那就根据资料配置好tomcat redis session manager，使用压力测试(集群切换分发更频繁)还是一样一部分成功一部分失败。也使用spring redis session试过了还是一样。

后来发现了一篇文章：https://blog.csdn.net/eguid_1/article/details/51444009

仔细分析了下spring web flow的源码，确定了问题就是出在webflow流程控制上，使用组播方式实现session复制也无济于事(也配过了，确实没有效果)，修改spring webflow的源码难度太大，绕过webflow登录流程代码改动太大。

为了寻找到更好的解决方案，继续分析、跟踪cas源码，从最底层错误开始分析

1. JcaCipherService.java:370

2. BinaryCipherExecutor.java:102

3. CasWebflowCipherBean.java:44

这一步发现调用的CipherExecutor是可以选择的，默认使用的为BinaryCipherExecutor。既然BinaryCipherExecutor里报错那就换NoOpCipherExecutor试试看。因为NoOpCipherExecutor的encode和decode方法的参数和返回值是String类型

而CasWebflowCipherBean调用时传的是byte[]：

  1. @Override
  2. public byte[] decrypt(final byte[] bytes) {
  3.     return webflowCipherExecutor.decode(bytes);
  4. }

那么就自定义一个CipherExecutor，代码如下：

  1. package org.jasig.cas.util;
  2.  
  3. import org.slf4j.Logger;
  4. import org.slf4j.LoggerFactory;
  5. import org.springframework.stereotype.Component;
  6.  
  7. /**
  8.  * No-Op cipher executor that does nothing for encryption/decryption.
  9.  * @author Misagh Moayyed
  10.  * @since 4.1
  11.  */
  12. @Component("noOpByteCipherExecutor")
  13. public final class NoOpByteCipherExecutor extends AbstractCipherExecutor<byte[], byte[]> {
  14.  
  15.     private static final Logger LOGGER = LoggerFactory.getLogger(NoOpByteCipherExecutor.class);
  16.  
  17.     /**
  18.      * Instantiates a new No-Op cipher executor.
  19.      * Issues a warning on safety.
  20.      */
  21.     public NoOpByteCipherExecutor() {
  22.         super(NoOpByteCipherExecutor.class.getName());
  23.         LOGGER.warn("[{}] does no encryption and may NOT be safe in a production environment. "
  24.                 + "Consider using other choices, such as [{}] that handle encryption, signing and verification of "
  25.                 + "all appropriate values.", this.getClass().getName(), BaseStringCipherExecutor.class.getName());
  26.     }
  27.  
  28.     @Override
  29.     public byte[] encode(final byte[] value) {
  30.         return value;
  31.     }
  32.  
  33.     @Override
  34.     public byte[] decode(final byte[] value) {
  35.         return value;
  36.     }
  37. }

然后在cas-servlet.xml中配置：

  1. <!-- 自定义CipherExecutor -->
  2. <bean id="loginFlowCipherBean" class="org.jasig.cas.web.flow.CasWebflowCipherBean" >
  3. 　　<constructor-arg ref="noOpByteCipherExecutor" />
    </bean>

要实现集群单点登录还需要在deployerConfigContext.xml增加如下配置：

  1. <!-- 注入noOpCookieValueManager -->
  2. <bean id="ticketGrantingTicketCookieGenerator" class="org.jasig.cas.web.support.TGCCookieRetrievingCookieGenerator">
  3.     <constructor-arg  ref="noOpCookieValueManager" />
  4. </bean>

至此实现了集群下的单点登录功能。

版权声明：本文为博主原创文章，转载需注明出处。http://www.cnblogs.com/bryanx/p/9044473.html

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