Spring Security 内置的InMemoryUserDetailsManager配置过程

InMemoryUserDetailsManager是Spring Security 内置的实现UserDetailsManager 接口的默认配置实现。它主要负责从配置文件中加载用户的账户信息。观察Spring Security源代码可清晰发现其配置过程。

1. UserServiceBeanDefinitionParser类解析配置文件<user-service>元素。代码第6行：

   private void loadParsers() {
           // Parsers
           parsers.put(Elements.LDAP_PROVIDER, new LdapProviderBeanDefinitionParser());
           parsers.put(Elements.LDAP_SERVER, new LdapServerBeanDefinitionParser());
           parsers.put(Elements.LDAP_USER_SERVICE, new LdapUserServiceBeanDefinitionParser());
           parsers.put(Elements.USER_SERVICE, new UserServiceBeanDefinitionParser());
           parsers.put(Elements.JDBC_USER_SERVICE, new JdbcUserServiceBeanDefinitionParser());
           parsers.put(Elements.AUTHENTICATION_PROVIDER, new AuthenticationProviderBeanDefinitionParser());
           parsers.put(Elements.GLOBAL_METHOD_SECURITY, new GlobalMethodSecurityBeanDefinitionParser());
           parsers.put(Elements.AUTHENTICATION_MANAGER, new AuthenticationManagerBeanDefinitionParser());
           parsers.put(Elements.METHOD_SECURITY_METADATA_SOURCE, new MethodSecurityMetadataSourceBeanDefinitionParser());
   
           // Only load the web-namespace parsers if the web classes are available
           if(ClassUtils.isPresent(FILTER_CHAIN_PROXY_CLASSNAME, getClass().getClassLoader())) {
               parsers.put(Elements.DEBUG, new DebugBeanDefinitionParser());
               parsers.put(Elements.HTTP, new HttpSecurityBeanDefinitionParser());
               parsers.put(Elements.HTTP_FIREWALL, new HttpFirewallBeanDefinitionParser());
               parsers.put(Elements.FILTER_INVOCATION_DEFINITION_SOURCE, new FilterInvocationSecurityMetadataSourceParser());
               parsers.put(Elements.FILTER_SECURITY_METADATA_SOURCE, new FilterInvocationSecurityMetadataSourceParser());
               parsers.put(Elements.FILTER_CHAIN, new FilterChainBeanDefinitionParser());
               filterChainMapBDD = new FilterChainMapBeanDefinitionDecorator();
           }
       }

    
2. UserServiceBeanDefinitionParser类有一个方法：getBeanClassName：

   protected String getBeanClassName(Element element) {
           return InMemoryUserDetailsManager.class.getName();
       }

    
3. UserServiceBeanDefinitionParser父类AbstractUserDetailsServiceBeanDefinitionParser的parse方法内部创建InMemoryUserDetailsManager，代码第2行：

   public BeanDefinition parse(Element element, ParserContext parserContext) {
           BeanDefinitionBuilder builder = BeanDefinitionBuilder.rootBeanDefinition(getBeanClassName(element));
   
           doParse(element, parserContext, builder);
   
           RootBeanDefinition userService = (RootBeanDefinition) builder.getBeanDefinition();
           final String beanId = resolveId(element, userService, parserContext);
   
           parserContext.registerBeanComponent(new BeanComponentDefinition(userService, beanId));
   
           String cacheRef = element.getAttribute(CACHE_REF);
   
           // Register a caching version of the user service if there's a cache-ref
           if (StringUtils.hasText(cacheRef)) {
               BeanDefinitionBuilder cachingUSBuilder = BeanDefinitionBuilder.rootBeanDefinition(CachingUserDetailsService.class);
               cachingUSBuilder.addConstructorArgReference(beanId);
   
               cachingUSBuilder.addPropertyValue("userCache", new RuntimeBeanReference(cacheRef));
               BeanDefinition cachingUserService = cachingUSBuilder.getBeanDefinition();
               parserContext.registerBeanComponent(new BeanComponentDefinition(cachingUserService, beanId + CACHING_SUFFIX));
           }
   
           return null;
       }