前言
最近敌人部门接手供方微服务项目过去运维，那套微服务的技术栈是springcloud Netflix，和敌人部门的微服务技术栈刚好匹配。过后敌人部门的想法，既然都是同一套技术体系，那些根底服务治理组件比方注册核心之类，就共用同一套。然而在落地施行的过程中，发现供方提供的微服务项目服务有些serviceId和敌人部门他们已有服务serviceId名字居然截然不同。这样就有问题了，eureka服务发现是通过serviceId辨认
敌人部门的策略是将供方微服务项目serviceId改掉，比方本来serviceId是user，就改成xxx-user。然而调整后，发现供方微服务某些微服务会报错，前面理解到供方仅提供应用层代码，有些外围代码库他们是不提供的。敌人他们部门也思考要不就替换本人已有服务的serviceId，后边发现可行性也不大，因为敌人他们微服务也对其余部门输入了一些能力，如果改变，就得告诉相干方进行改变，这边会波及到一些沟通老本等非技术性因素。
后边敌人就和我交换了一下计划。首先问题点的实质是serviceId一样引起的吗？乍看一下，如同是这样。咱们换个角度思考这个问题，是不是也能够说是因为隔离性做得不够好导致。于是我就跟敌人说，如果把eureka切换成nacos，对你部门的切换老本大不大。敌人说代码层尽管仅需切换jar和配置即可实现，然而因为版本起因，如果切换，他们也只能用到nacos 1版本的能力。其次他部门对注册核心的性能要求也不高，但对注册核心的稳定性要求比拟高，如果切换，他们须要做很多测试方面的工作，仅仅只是因为这个隔离性，他更偏向部署多个eureka。
聊到前面敌人就在吐槽eureka，为啥不能像nacos或者k8s那样搞个namespace来做隔离。基于敌人这个想法，我就跟他说，我帮你扩大一下，让eureka也领有仿nacos namespace的能力
实现思路
注: 本文以敌人他们公司的微服务版本springcloud Hoxton.SR3来解说
实现的外围逻辑：利用注册核心都有的元数据，即metaMap，以及配合注册核心具备的服务发现能力进行扩大
外围实现逻辑
1、元数据扩大
a、新建扩大配置类
@ConfigurationProperties(prefix = "eureka.instance.ext")@Data@AllArgsConstructor@NoArgsConstructorpublic class EurekaInstanceProperties { private String namespace = Constant.META_INFO_DEAFULT_NAMESPACE; private String group = Constant.META_INFO_DEAFULT_GROUP; private boolean loadBalanceAllowCross;}b、元数据扩大填充
public class EurekaInstanceSmartInitializingSingleton implements SmartInitializingSingleton, ApplicationContextAware { private ApplicationContext applicationContext; @Override public void afterSingletonsInstantiated() { EurekaInstanceProperties eurekaInstanceProperties = applicationContext.getBean(EurekaInstanceProperties.class); EurekaInstanceConfigBean bean = applicationContext.getBean(EurekaInstanceConfigBean.class); Map<String, String> metadataMap = bean.getMetadataMap(); metadataMap.put(Constant.META_INFO_KEY_NAMESPACE,eurekaInstanceProperties.getNamespace()); metadataMap.put(Constant.META_INFO_KEY_GROUP,eurekaInstanceProperties.getGroup()); } @Override public void setApplicationContext(ApplicationContext applicationContext) throws BeansException { this.applicationContext = applicationContext; }}2、eureka服务端面板革新
a、status.ftlh页面逻辑革新
在我的项目eureka服务端的src/main/resource目录下新建/templates/eureka文件夹，将eureka本来有的status.ftlh拷贝过去，因为咱们要对这个status.ftlh进行革新。而status.ftlh本来地位是放在
在status.ftlh增加如下内容
b、微调EurekaController内容
EurekaController是eureka服务用来面板展现的控制器，能够在eureka的服务端的我的项目建一个EurekaController截然不同的类，形如
注： 也能够本人自定义一个controller，反正这个controller就是用来页面渲染用的
对如下办法进行微调
org.springframework.cloud.netflix.eureka.server.EurekaController#populateApps微调内容如下
for (InstanceInfo info : app.getInstances()) { String id = info.getId(); String url = info.getStatusPageUrl(); Map<String, String> metadata = info.getMetadata(); String group = StringUtils.isEmpty(metadata.get("group")) ? "default" : metadata.get("group"); String namespace = StringUtils.isEmpty(metadata.get("namespace")) ? "default" : metadata.get("namespace"); String metaInfo = url + "_" + namespace + "_" + group; List<Pair<String, String>> list = instancesByStatus .computeIfAbsent(status, k -> new ArrayList<>()); list.add(new Pair<>(id, metaInfo)); } for (Map.Entry<InstanceInfo.InstanceStatus, List<Pair<String, String>>> entry : instancesByStatus .entrySet()) { List<Pair<String, String>> value = entry.getValue(); InstanceInfo.InstanceStatus status = entry.getKey(); LinkedHashMap<String, Object> instanceData = new LinkedHashMap<>(); for (Pair<String, String> p : value) { LinkedHashMap<String, Object> instance = new LinkedHashMap<>(); instances.add(instance); instance.put("id", p.first()); String metaInfo = p.second(); String[] metaInfoArr = metaInfo.split("_"); String url = metaInfoArr[0]; instance.put("url", url); String namespace = metaInfoArr[1]; instance.put("namespace", namespace); String group = metaInfoArr[2]; instance.put("group", group); boolean isHref = url != null && url.startsWith("http"); instance.put("isHref", isHref); } model.put("apps", apps);c、革新后的面板展现
注： 在eureka的客户端需配形如下配置
3、服务发现革新
a、重写com.netflix.loadbalancer.ServerList
参照eureka的服务发现配置类
@Bean @ConditionalOnMissingBean public ServerList<?> ribbonServerList(IClientConfig config, Provider<EurekaClient> eurekaClientProvider) { if (this.propertiesFactory.isSet(ServerList.class, serviceId)) { return this.propertiesFactory.get(ServerList.class, config, serviceId); } DiscoveryEnabledNIWSServerList discoveryServerList = new DiscoveryEnabledNIWSServerList( config, eurekaClientProvider); DomainExtractingServerList serverList = new DomainExtractingServerList( discoveryServerList, config, this.approximateZoneFromHostname); return serverList; }咱们能够发现咱们仅需革新DiscoveryEnabledNIWSServerList即可
@Slf4jpublic class CustomDiscoveryEnabledNIWSServerList extends DiscoveryEnabledNIWSServerList { private final Provider<EurekaClient> eurekaClientProvider; private final EurekaInstanceProperties eurekaInstanceProperties; public CustomDiscoveryEnabledNIWSServerList(IClientConfig clientConfig, Provider<EurekaClient> eurekaClientProvider,EurekaInstanceProperties eurekaInstanceProperties) { this.eurekaClientProvider = eurekaClientProvider; this.eurekaInstanceProperties = eurekaInstanceProperties; initWithNiwsConfig(clientConfig); } @Override public List<DiscoveryEnabledServer> getInitialListOfServers(){ List<DiscoveryEnabledServer> initialListOfServers = super.getInitialListOfServers(); return selectListOfServersByMetaInfo(initialListOfServers); } @Override public List<DiscoveryEnabledServer> getUpdatedListOfServers(){ List<DiscoveryEnabledServer> updatedListOfServers = super.getUpdatedListOfServers(); return selectListOfServersByMetaInfo(updatedListOfServers); } private List<DiscoveryEnabledServer> selectListOfServersByMetaInfo(List<DiscoveryEnabledServer> discoveryEnabledServerList){ List<DiscoveryEnabledServer> discoveryEnabledServersByMetaInfo = new ArrayList<>(); if(!CollectionUtils.isEmpty(discoveryEnabledServerList)){ for (DiscoveryEnabledServer discoveryEnabledServer : discoveryEnabledServerList) { Map<String, String> metadata = discoveryEnabledServer.getInstanceInfo().getMetadata(); String namespace = metadata.get(Constant.META_INFO_KEY_NAMESPACE); String group = metadata.get(Constant.META_INFO_KEY_GROUP); if(eurekaInstanceProperties.getNamespace().equals(namespace) && eurekaInstanceProperties.getGroup().equals(group)){ discoveryEnabledServersByMetaInfo.add(discoveryEnabledServer); } } } if(CollectionUtils.isEmpty(discoveryEnabledServersByMetaInfo) && eurekaInstanceProperties.isLoadBalanceAllowCross()){ log.warn("not found enabledServerList in namespace : 【{}】 and group : 【{}】. will select default enabledServerList by isLoadBalanceAllowCross is {}",eurekaInstanceProperties.getNamespace(),eurekaInstanceProperties.getGroup(),eurekaInstanceProperties.isLoadBalanceAllowCross()); return discoveryEnabledServerList; } return discoveryEnabledServersByMetaInfo; }}b、配置咱们重写后的ServerList
@Configurationpublic class EurekaClientAutoConfiguration extends EurekaRibbonClientConfiguration{ @Value("${ribbon.eureka.approximateZoneFromHostname:false}") private boolean approximateZoneFromHostname = false; @RibbonClientName private String serviceId = "client";; @Autowired private PropertiesFactory propertiesFactory; @Bean @Primary public ServerList<?> ribbonServerList(IClientConfig config, Provider<EurekaClient> eurekaClientProvider, EurekaInstanceProperties properties) { if (this.propertiesFactory.isSet(ServerList.class, serviceId)) { return this.propertiesFactory.get(ServerList.class, config, serviceId); } DiscoveryEnabledNIWSServerList discoveryServerList = new CustomDiscoveryEnabledNIWSServerList( config, eurekaClientProvider,properties); DomainExtractingServerList serverList = new DomainExtractingServerList( discoveryServerList, config, this.approximateZoneFromHostname); return serverList; }}c、批改ribbionclient的默认配置
@Configuration(proxyBeanMethods = false)@EnableConfigurationProperties@ConditionalOnRibbonAndEurekaEnabled@AutoConfigureAfter(RibbonAutoConfiguration.class)@RibbonClients(defaultConfiguration = EurekaClientAutoConfiguration.class)public class RibbonEurekaAutoConfiguration {}测试
示例服务：网关、消费者服务、提供者服务、eureka
相干的eureka配置内容如下
1、网关：
网关占用端口：8000
eureka: instance: instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${spring.application.instance_id:${server.port}} prefer-ip-address: ${PREFER_IP:true} #是否抉择IP注册 # ip-address: ${IP_ADDRESS:localhost} #指定IP地址注册 lease-renewal-interval-in-seconds: 5 #续约更新工夫距离（默认30秒）,使得eureka及时剔除有效服务 lease-expiration-duration-in-seconds: 10 #续约到期工夫（默认90秒） hostname: ${HOSTNAME:${spring.application.name}} ext: namespace: dev group: lybgeek client: service-url: defaultZone: ${EUREKA_CLIENT_SERVICEURL_DEFAULTZONE:http://localhost:8761/eureka/} #缩短提早向服务端注册的工夫、默认40s initial-instance-info-replication-interval-seconds: 10 #进步Eureka-Client端拉取Server注册信息的频率,默认30s registry-fetch-interval-seconds: 52、消费者
消费者1： 占用端口：6614
eureka: instance: instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${spring.application.instance_id:${server.port}} prefer-ip-address: ${PREFER_IP:true} #是否抉择IP注册 # ip-address: ${IP_ADDRESS:localhost} #指定IP地址注册 lease-renewal-interval-in-seconds: 5 #续约更新工夫距离（默认30秒）,使得eureka及时剔除有效服务 lease-expiration-duration-in-seconds: 10 #续约到期工夫（默认90秒） hostname: ${HOSTNAME:${spring.application.name}} ext: group: lybgeek namespace: dev client: service-url: defaultZone: ${EUREKA_CLIENT_SERVICEURL_DEFAULTZONE:http://localhost:8761/eureka/} #缩短提早向服务端注册的工夫、默认40s initial-instance-info-replication-interval-seconds: 10 #进步Eureka-Client端拉取Server注册信息的频率,默认30s registry-fetch-interval-seconds: 5消费者2： 占用端口：6613
eureka: instance: instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${spring.application.instance_id:${server.port}} prefer-ip-address: ${PREFER_IP:true} #是否抉择IP注册 # ip-address: ${IP_ADDRESS:localhost} #指定IP地址注册 lease-renewal-interval-in-seconds: 5 #续约更新工夫距离（默认30秒）,使得eureka及时剔除有效服务 lease-expiration-duration-in-seconds: 10 #续约到期工夫（默认90秒） hostname: ${HOSTNAME:${spring.application.name}} ext: group: lybgeek6613 namespace: dev client: service-url: defaultZone: ${EUREKA_CLIENT_SERVICEURL_DEFAULTZONE:http://localhost:8761/eureka/} #缩短提早向服务端注册的工夫、默认40s initial-instance-info-replication-interval-seconds: 10 #进步Eureka-Client端拉取Server注册信息的频率,默认30s registry-fetch-interval-seconds: 5管制层示例
@RestController@RequestMapping("instance")public class InstanceInfoController { @InstancePort private String port; @InstanceName private String instanceName; @Autowired private InstanceServiceFeign instanceServiceFeign; @GetMapping("list") public List<InstanceInfo> list(){ List<InstanceInfo> instanceInfos = new ArrayList<>(); InstanceInfo comsumeInstanceInfo = InstanceInfo.builder() .port(port).name(instanceName).build(); instanceInfos.add(comsumeInstanceInfo); InstanceInfo providerInstanceInfo = null; try { providerInstanceInfo = instanceServiceFeign.getInstanceInfo(); instanceInfos.add(providerInstanceInfo); } catch (Exception e) { e.printStackTrace(); } return instanceInfos; }}3、提供者
提供者1： 占用端口:6605
eureka: instance: instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${spring.application.instance_id:${server.port}} prefer-ip-address: ${PREFER_IP:true} #是否抉择IP注册 # ip-address: ${IP_ADDRESS:localhost} #指定IP地址注册 lease-renewal-interval-in-seconds: 5 #续约更新工夫距离（默认30秒）,使得eureka及时剔除有效服务 lease-expiration-duration-in-seconds: 10 #续约到期工夫（默认90秒） hostname: ${HOSTNAME:${spring.application.name}} ext: namespace: dev group: lybgeek client: service-url: defaultZone: ${EUREKA_CLIENT_SERVICEURL_DEFAULTZONE:http://localhost:8761/eureka/} #缩短提早向服务端注册的工夫、默认40s initial-instance-info-replication-interval-seconds: 10 #进步Eureka-Client端拉取Server注册信息的频率,默认30s registry-fetch-interval-seconds: 5提供者2： 占用端口:6604
eureka: instance: instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${spring.application.instance_id:${server.port}} prefer-ip-address: ${PREFER_IP:true} #是否抉择IP注册 # ip-address: ${IP_ADDRESS:localhost} #指定IP地址注册 lease-renewal-interval-in-seconds: 5 #续约更新工夫距离（默认30秒）,使得eureka及时剔除有效服务 lease-expiration-duration-in-seconds: 10 #续约到期工夫（默认90秒） hostname: ${HOSTNAME:${spring.application.name}} ext: namespace: dev group: lybgeek6613 client: service-url: defaultZone: ${EUREKA_CLIENT_SERVICEURL_DEFAULTZONE:http://localhost:8761/eureka/} #缩短提早向服务端注册的工夫、默认40s initial-instance-info-replication-interval-seconds: 10 #进步Eureka-Client端拉取Server注册信息的频率,默认30s registry-fetch-interval-seconds: 5管制层示例
@RestController@RequestMapping(InstanceServiceFeign.PATH)public class InstanceServiceFeignImpl implements InstanceServiceFeign { @InstancePort private String port; @InstanceName private String instanceName; @Override public InstanceInfo getInstanceInfo() { return InstanceInfo.builder() .name(instanceName).port(port).build(); }}拜访eureka面板
通过网关拜访会发现不论拜访多少次，网关只能命中namespace为dev、group为lybgeek的服务，阐明隔离成果失效
当咱们的服务和其余服务不属于同个namespace或者group时，能够通过配置load-balance-allow-cross: true，实现跨namespace和group拜访。配置形如下
eureka: instance: instance-id: ${spring.application.name}:${spring.cloud.client.ip-address}:${spring.application.instance_id:${server.port}} prefer-ip-address: ${PREFER_IP:true} #是否抉择IP注册 # ip-address: ${IP_ADDRESS:localhost} #指定IP地址注册 lease-renewal-interval-in-seconds: 5 #续约更新工夫距离（默认30秒）,使得eureka及时剔除有效服务 lease-expiration-duration-in-seconds: 10 #续约到期工夫（默认90秒） hostname: ${HOSTNAME:${spring.application.name}} ext: namespace: dev group: lybgeek123 load-balance-allow-cross: true咱们再通过网关拜访一下
察看控制台，会发现呈现正告
总结
本文次要是仿造nacos的一些思路，对eureka进行扩大。其实注册核心的性能大同小异，尤其集成springcloud后，基本上都有固定套路了。本文只是实现eureka 服务发现隔离的一种形式，也能够通过eureka自身的zone和region，通过自定义负载平衡策略来实现。最初eureka instance其实也有namespace的属性，只是在springcloud集成，被忽略了
demo链接
https://github.com/lyb-geek/springboot-cloud-metadata-ext