java - Spring 。在我的 CustomDataSource getConnection 方法中访问 session Bean

Question

有人知道如何在 DataSource getConnection 中访问 session 范围的 bean 吗？

我决定为每个客户端( Multi-Tenancy )实现一个单独的数据库模式，我发现这篇非常有前途的文章:Multitenancy using Spring and PostgreSQL ，并且一直在努力实现它所说的一段时间。

正如您在评论中看到的(我和其他人一样被卡住了)，由于 java.lang.IllegalStateException，它不起作用。还发现 this question在最后一条评论中，您可以在其中看到相同的内容。

作者(gargii)给出的答案是这样的:

The error message is probably a very good desciption of the state you are in. Try to think of it. Focus on threads. Which thread gets the original request? Which thread fails with the error? Try to debug the RequestContextHolder class. This is the place where the session-magic is actually done (using ThreadLocal).

好吧...我尝试调试但没有成功，我已经看到几十个页面试图解决问题，但仍然没有找到解决方案。

我总是遇到这个异常(我在最后复制了完整的跟踪):

2013-10-08 08:47:37,232 [localhost-startStop-1] ERROR org.springframework.web.context.ContextLoader - Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor#0': Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in file [C:\Users\ely\Documents\Desarrollo\Spring\springsource\vfabric-tc-server-developer-2.9.2.RELEASE\base-instance\wtpwebapps\TestMultiTenant\WEB-INF\classes\META-INF\spring\applicationContext.xml]: Invocation of init method failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.tenantContext': Scope 'session' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.

---

简而言之，这就是我得到的:

先于其他任何事情执行的安全过滤器 (applicationContext-Security.xml):

<custom-filter before="FIRST" ref="tenantFilter" />

过滤器是:

public class TenantFilter implements Filter {

private TenantContext tenantContext;
private TenantRepository tenantRepository;
...

应用程序上下文.xml:

<bean id="tenantFilter" class="com.i4b.test1.core.TenantFilter">
    <property name="tenantContext" ref="tenantContext" />
    <property name="tenantRepository" ref="tenantRepository" />
</bean>

TenantContext 有:

@Component
@RooJavaBean
@RooToString
@Scope(value = "session", proxyMode = ScopedProxyMode.TARGET_CLASS)
public class TenantContext {
    private Tenant tenant;
    private String idSchema;
} 

(注意它不是 RooEntity 或 RooActiveRecord。我只是使用 @RooJavaBean 和 @RooToString 来自动创建 setter、getter 和 toString)

在 web.xml 中强制配置:

<!-- ADDED FOR MULTI TENANCY START -->
<listener>
  <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
</listener>
<!-- MULTI TENANCY END -->

<!-- Creates the Spring Container shared by all Servlets and Filters -->
<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

和applicationContext.xml:

<bean id="tenantContext" class="com.i4b.test1.core.TenantContext" scope="session">
    <aop:scoped-proxy />
</bean>

还有:

@Component
public class TenantAwareDataSource extends BasicDataSource  {

@Autowired
private TenantContext tenantContext;

// [tenant,schema] to [DataSource] mapping
private final Map<String, BasicDataSource> schemaToDataSource = new HashMap<String, BasicDataSource>();

...
@Override
public Connection getConnection() throws SQLException {
    BasicDataSource determineTargetDataSource = determineTargetDataSource();
    return determineTargetDataSource.getConnection();
}

这个类在applicationContext.xml中配置:

<bean class="com.i4b.test1.core.TenantAwareDataSource" destroy-method="close" id="dataSource">
    <property name="driverClassName" value="${database.driverClassName}"/>
    <property name="url" value="${database.url}"/>
    <property name="username" value="${database.username}"/>
    <property name="password" value="${database.password}"/>
    <property name="testOnBorrow" value="true"/>
    <property name="testOnReturn" value="true"/>
    <property name="testWhileIdle" value="true"/>
    <property name="timeBetweenEvictionRunsMillis" value="1800000"/>
    <property name="numTestsPerEvictionRun" value="3"/>
    <property name="minEvictableIdleTimeMillis" value="1800000"/>
    <property name="validationQuery" value="SELECT version();"/>
</bean>

If I remove the @Autowired from "TenantAwareDataSource" shown code, it doesn't give me the exception, but doesn't really work. hahaha. tenantContext is always null because it's not the session bean anymore.

顺便说一句。此应用程序是使用以下版本 (pom.xml) 创建的:

<properties>
    <aspectj.version>1.7.2</aspectj.version>
    <java.version>7</java.version>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <roo.version>1.2.4.RELEASE</roo.version>
    <slf4j.version>1.7.5</slf4j.version>
    <spring.version>3.2.3.RELEASE</spring.version>
    <spring-security.version>3.1.0.RELEASE</spring-security.version>
</properties>

最后，完整的异常(exception)是:

2013-10-08 08:47:37,232 [localhost-startStop-1] ERROR org.springframework.web.context.ContextLoader - Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor#0': Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in file [C:\Users\ely\Documents\Desarrollo\Spring\springsource\vfabric-tc-server-developer-2.9.2.RELEASE\base-instance\wtpwebapps\TestMultiTenant\WEB-INF\classes\META-INF\spring\applicationContext.xml]: Invocation of init method failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.tenantContext': Scope 'session' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:529)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:198)
    at org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:741)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:464)
    at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:389)
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:294)
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:112)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4887)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5381)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:657)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1637)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
    at java.util.concurrent.FutureTask.run(FutureTask.java:166)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:724)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in file [C:\Users\ely\Documents\Desarrollo\Spring\springsource\vfabric-tc-server-developer-2.9.2.RELEASE\base-instance\wtpwebapps\TestMultiTenant\WEB-INF\classes\META-INF\spring\applicationContext.xml]: Invocation of init method failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.tenantContext': Scope 'session' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1482)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:198)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:439)
    at org.springframework.beans.factory.BeanFactoryUtils.beansOfTypeIncludingAncestors(BeanFactoryUtils.java:277)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.detectPersistenceExceptionTranslators(PersistenceExceptionTranslationInterceptor.java:139)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.<init>(PersistenceExceptionTranslationInterceptor.java:79)
    at org.springframework.dao.annotation.PersistenceExceptionTranslationAdvisor.<init>(PersistenceExceptionTranslationAdvisor.java:71)
    at org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor.setBeanFactory(PersistenceExceptionTranslationPostProcessor.java:85)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeAwareMethods(AbstractAutowireCapableBeanFactory.java:1502)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1470)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521)
    ... 24 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.tenantContext': Scope 'session' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:343)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.aop.target.SimpleBeanTargetSource.getTarget(SimpleBeanTargetSource.java:34)
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.getTarget(CglibAopProxy.java:663)
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:614)
    at com.i4b.test1.core.TenantContext$$EnhancerByCGLIB$$c51ab566.getTenant(<generated>)
    at com.i4b.test1.core.TenantContext_Roo_JavaBean.ajc$interMethodDispatch1$com_i4b_test1_core_TenantContext_Roo_JavaBean$com_i4b_test1_core_TenantContext$getTenant(TenantContext_Roo_JavaBean.aj)
    at com.i4b.test1.core.TenantAwareDataSource.currentLookupKey(TenantAwareDataSource.java:77)
    at com.i4b.test1.core.TenantAwareDataSource.determineTargetDataSource(TenantAwareDataSource.java:99)
    at com.i4b.test1.core.TenantAwareDataSource.getConnection(TenantAwareDataSource.java:216)
    at org.hibernate.ejb.connection.InjectedDataSourceConnectionProvider.getConnection(InjectedDataSourceConnectionProvider.java:70)
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl$ConnectionProviderJdbcConnectionAccess.obtainConnection(JdbcServicesImpl.java:242)
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:117)
    at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:75)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:159)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:131)
    at org.hibernate.cfg.Configuration.buildTypeRegistrations(Configuration.java:1797)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1755)
    at org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:96)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:914)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:899)
    at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:76)
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:288)
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:310)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1541)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1479)
    ... 39 more
Caused by: java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
    at org.springframework.web.context.request.RequestContextHolder.currentRequestAttributes(RequestContextHolder.java:131)
    at org.springframework.web.context.request.SessionScope.get(SessionScope.java:90)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:329)
    ... 64 more `

Answer 1

您的 DataSource 可能在发出任何请求之前很久就被实例化了(请注意日志中的 Bootstrap 线程名称 - [localhost-startStop-1])。所以实际上没有 SESSION 可以被 Spring 用来满足 SESSION 范围。

您需要手动实现 session 范围(通过 RequestContextHolder)或使组件松耦合(例如通过 ApplicationContext#getBean)。

---

我们在几个项目上所做的就是将TenantContext实现为ThreadLocal变量(类似于Spring Security的SecurityContext)，正在设置并通过特殊的 servlet Filter 取消设置。这是迄今为止最好的方法，因为没有组件会依赖于实际存在 Activity HTTP 请求这一事实。

总而言之 - 对于您的特定用例，如果没有任何 session 作用域的 bean，您会过得更好。

---

旁注:如果您使用的是 Hibernate，请注意已经有一个 support for multi-tenancy .其他框架也可能支持它。