Eureka Server启动（一）

start包配置

spring-cloud-netflix-eureka-server包结构

在这个包下面META-INF下面有个spring.factories这个配置文件

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
org.springframework.cloud.netflix.eureka.server.EurekaServerAutoConfiguration

使用了springboot EnableAutoConfiguration这个注解，在springboot应用启动的时候，会自动加载

EurekaServerAutoConfiguration这个bean，后面主要看这个bean的源码

启动源码分析

EurekaServerAutoConfiguration

用于EurekaServer往beanfactory添加相关eureka-server功能bean

@Configuration
@Import(EurekaServerInitializerConfiguration.class)
@ConditionalOnBean(EurekaServerMarkerConfiguration.Marker.class)
@EnableConfigurationProperties({ EurekaDashboardProperties.class,
InstanceRegistryProperties.class})
@PropertySource("classpath:/eureka/server.properties")
publicclassextendsWebMvcConfigurerAdapter {
// 此处省略大部分代码，仅抽取一些关键的代码片段
// 加载EurekaController, spring-cloud 提供了一些额外的接口，用来获取eurekaServer的信息
@Bean
@ConditionalOnProperty"eureka.dashboard""enabled"true)
publicEurekaController eurekaController() {
returnnewEurekaController(this.applicationInfoManager);
}
// 配置服务节点信息，这里的作用主要是为了配置Eureka的peer节点，也就是说当有收到有节点注册上来
//的时候，需要通知给那些服务节点， （互为一个集群）
@Bean
@ConditionalOnMissingBean
publicPeerEurekaNodes peerEurekaNodes(PeerAwareInstanceRegistry registry,
ServerCodecs serverCodecs) {
returnnewthis.eurekaServerConfig,
thisthis.applicationInfoManager);
}
// EurekaServer的上下文
@Bean
publicEurekaServerContext eurekaServerContext(ServerCodecs serverCodecs,
PeerAwareInstanceRegistry registry, PeerEurekaNodes peerEurekaNodes) {
returnnewDefaultEurekaServerContext(this.eurekaServerConfig, serverCodecs,
this.applicationInfoManager);
}
// 这个类的作用是spring-cloud和原生eureka的胶水代码，通过这个类来启动EurekaSever
// 后面这个类会在EurekaServerInitializerConfiguration被调用，进行eureka启动
@Bean
publicEurekaServerBootstrap eurekaServerBootstrap(PeerAwareInstanceRegistry registry,
EurekaServerContext serverContext) {
returnnewEurekaServerBootstrap(this.applicationInfoManager,
thisthis.eurekaServerConfig, registry,
serverContext);
}
// 配置拦截器，ServletContainer里面实现了jersey框架，通过他来实现eurekaServer对外的restFull接口
@Bean
publicFilterRegistrationBean jerseyFilterRegistration(
javax.ws.rs.core.Application eurekaJerseyApp) {
newFilterRegistrationBean();
bean.setFilter(newServletContainer(eurekaJerseyApp));
bean.setOrder(Ordered.LOWEST_PRECEDENCE);
bean.setUrlPatterns(
"/*"));
returnbean;
}
// 拦截器实例
@Bean
publicjavax.ws.rs.core.Application jerseyApplication(Environment environment,
ResourceLoader resourceLoader) {
newClassPathScanningCandidateComponentProvider(
false, environment);
// Filter to include only classes that have a particular annotation.
//
provider.addIncludeFilter(newAnnotationTypeFilter(Path.class));
provider.addIncludeFilter(newAnnotationTypeFilter(Provider.class));
// Find classes in Eureka packages (or subpackages)
//
newHashSet<Class<?>>();
for(String basePackage : EUREKA_PACKAGES) {
Set<BeanDefinition> beans = provider.findCandidateComponents(basePackage);
for(BeanDefinition bd : beans) {
Class<?> cls = ClassUtils.resolveClassName(bd.getBeanClassName(),
resourceLoader.getClassLoader());
classes.add(cls);
}
}
// Construct the Jersey ResourceConfig
//
newHashMap<String, Object>();
propsAndFeatures.put(
// Skip static content used by the webapp
ServletContainer.PROPERTY_WEB_PAGE_CONTENT_REGEX,
"/(fonts|images|css|js)/.*");
newDefaultResourceConfig(classes);
rc.setPropertiesAndFeatures(propsAndFeatures);
returnrc;
}
}

1.@Configuration 表明这是一个配置类

2.@Import(EurekaServerInitializerConfiguration.class) 导入启动EurekaServer的bean

3.@ConditionalOnBean(EurekaServerMarkerConfiguration.Marker.class)  这个是表示只有在spring容器

里面含有Market这个实例的时候，才会加载当前这个Bean（EurekaServerAutoConfiguration ），这个就是控制

是否开启EurekaServer的关键，在@EableEurekaServer这个注解里面，就是创建了一个Market兑现，用来

告诉他，我开启了Eureka服务

4.@EnableConfigurationProperties({ EurekaDashboardProperties.class, InstanceRegistryProperties.class })

加载配置

EurekaServerInitializerConfiguration

从上面的代码分析上可以看到，在EurekaServerAutoConfiguration加载完成之后就会执行

EurekaServerInitializerConfiguration这个类的start方法，这个类实现了spring的SmartLifecyl,具体可以

可以看这个SmartLifecycle，里面有详细的介绍。

EurekaServerInitializerConfiguration

/**
* @author Dave Syer
*/
@Configuration
@CommonsLog
publicclassEurekaServerInitializerConfiguration
implementsServletContextAware, SmartLifecycle, Ordered {
@Autowired
privateEurekaServerConfig eurekaServerConfig;
privateServletContext servletContext;
@Autowired
privateApplicationContext applicationContext;

标签

eureka