诚之和:如何理解NacosRibbonClientConfiguration
今天就跟大家聊聊有关如何理解NacosRibbonClientConfiguration,可能很多人都不太了解,为了让大家更加了解,小编给大家总结了以下内容,希望大家根据这篇文章可以有所收获。
序
本文主要研究一下NacosRibbonClientConfiguration
NacosRibbonClientConfiguration
spring-cloud-alibaba-0.9.0.RELEASE/spring-cloud-alibaba-nacos-discovery/src/main/java/org/springframework/cloud/alibaba/nacos/ribbon/NacosRibbonClientConfiguration.java
@Configuration@ConditionalOnRibbonNacospublic class NacosRibbonClientConfiguration {@Bean @ConditionalOnMissingBean public ServerList<?> ribbonServerList(IClientConfig config, NacosDiscoveryProperties nacosDiscoveryProperties) { NacosServerList serverList = new NacosServerList(nacosDiscoveryProperties); serverList.initWithNiwsConfig(config);return serverList; } }
NacosRibbonClientConfiguration会创建NacosServerList
NacosServerList
spring-cloud-alibaba-0.9.0.RELEASE/spring-cloud-alibaba-nacos-discovery/src/main/java/org/springframework/cloud/alibaba/nacos/ribbon/NacosServerList.java
public class NacosServerList extends AbstractServerList<NacosServer> {private NacosDiscoveryProperties discoveryProperties;private String serviceId;public NacosServerList(NacosDiscoveryProperties discoveryProperties) {this.discoveryProperties = discoveryProperties; }@Override public List<NacosServer> getInitialListOfServers() {return getServers(); }@Override public List<NacosServer> getUpdatedListOfServers() {return getServers(); }private List<NacosServer> getServers() {try { List<Instance> instances = discoveryProperties.namingServiceInstance() .selectInstances(serviceId, true);return instancesToServerList(instances); }catch (Exception e) {throw new IllegalStateException("Can not get service instances from nacos, serviceId=" + serviceId, e); } }private List<NacosServer> instancesToServerList(List<Instance> instances) { List<NacosServer> result = new ArrayList<>();if (null == instances) {return result; }for (Instance instance : instances) { result.add(new NacosServer(instance)); }return result; }public String getServiceId() {return serviceId; }@Override public void initWithNiwsConfig(IClientConfig iClientConfig) {this.serviceId = iClientConfig.getClientName(); } }
NacosServerList继承了com.netflix.loadbalancer.AbstractServerList,其getInitialListOfServers及getUpdatedListOfServers方法都是调用了getServers;getServers方法则是通过NamingService.selectInstances来获取服务实例信息
NacosServer
spring-cloud-alibaba-0.9.0.RELEASE/spring-cloud-alibaba-nacos-discovery/src/main/java/org/springframework/cloud/alibaba/nacos/ribbon/NacosServer.java
public class NacosServer extends Server {private final MetaInfo metaInfo;private final Instance instance;private final Map<String, String> metadata;public NacosServer(final Instance instance) {super(instance.getIp(), instance.getPort());this.instance = instance;this.metaInfo = new MetaInfo() {@Override public String getAppName() {return instance.getServiceName(); }@Override public String getServerGroup() {return null; }@Override public String getServiceIdForDiscovery() {return null; }@Override public String getInstanceId() {return instance.getInstanceId(); } };this.metadata = instance.getMetadata(); }@Override public MetaInfo getMetaInfo() {return metaInfo; }public Instance getInstance() {return instance; }public Map<String, String> getMetadata() {return metadata; } }
NacosServer继承了com.netflix.loadbalancer.Server;它主要有metaInfo、instance、metadata三个属性
小结
NacosRibbonClientConfiguration会创建NacosServerList;NacosServerList继承了com.netflix.loadbalancer.AbstractServerList,其getInitialListOfServers及getUpdatedListOfServers方法都是调用了getServers;getServers方法则是通过NamingService.selectInstances来获取服务实例信息