源码环境搭建
源码下载地址github.com/alibaba/nac…
文件目录
由于nacos采用了protobuf，在consistency模块下会有一些类缺失。
protobuf是谷歌内部的混合语言数据标准。通过将结构化的数据进行序列化(串行化)，用于通讯协议、数据存储等领域的语言无关、平台无关、可扩展的序列化结构数据格式。
解决方案
- 插件下载
- 通过mvn copmpile来在target自动生成
启动
添加参数-Dnacos.standalone=true(单机启动)
服务注册(客户端)
导入nacos依赖
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>
找到springboot自动装配下扫描类路径下的META-INF/spring.factories文件
配置文件
@Configuration(proxyBeanMethods = false)
@EnableConfigurationProperties
@ConditionalOnNacosDiscoveryEnabled
@ConditionalOnProperty(value = "spring.cloud.service-registry.auto-registration.enabled",
matchIfMissing = true)
@AutoConfigureAfter({ AutoServiceRegistrationConfiguration.class,
AutoServiceRegistrationAutoConfiguration.class,
NacosDiscoveryAutoConfiguration.class })
public class NacosServiceRegistryAutoConfiguration {
@Bean
public NacosServiceRegistry nacosServiceRegistry(
NacosDiscoveryProperties nacosDiscoveryProperties) {
return new NacosServiceRegistry(nacosDiscoveryProperties);
}
@Bean
@ConditionalOnBean(AutoServiceRegistrationProperties.class)
public NacosRegistration nacosRegistration(
ObjectProvider<List<NacosRegistrationCustomizer>> registrationCustomizers,
NacosDiscoveryProperties nacosDiscoveryProperties,
ApplicationContext context) {
return new NacosRegistration(registrationCustomizers.getIfAvailable(),
nacosDiscoveryProperties, context);
}
@Bean
@ConditionalOnBean(AutoServiceRegistrationProperties.class)
public NacosAutoServiceRegistration nacosAutoServiceRegistration(
NacosServiceRegistry registry,
AutoServiceRegistrationProperties autoServiceRegistrationProperties,
NacosRegistration registration) {
//核心
return new NacosAutoServiceRegistration(registry,
autoServiceRegistrationProperties, registration);
}
}
NacosAutoServiceRegistration
看上面配置可知NacosAutoServiceRegistration作为Bean是要依赖于前两项的Bean(NacosServiceRegistry和NacosRegistration)
类结构图
实现了ApplicationListener事件监听机制，那么就会重写他的onApplicationEvent()
AbstractAutoServiceRegistration#bind(WebServerInitializedEvent event)
public void onApplicationEvent(WebServerInitializedEvent event) {
this.bind(event);
}
public void bind(WebServerInitializedEvent event) {
ApplicationContext context = event.getApplicationContext();
if (!(context instanceof ConfigurableWebServerApplicationContext) || !"management".equals(((ConfigurableWebServerApplicationContext)context).getServerNamespace())) {
this.port.compareAndSet(0, event.getWebServer().getPort());
//开始
this.start();
}
}
public void start() {
if (!this.isEnabled()) {
if (logger.isDebugEnabled()) {
logger.debug("Discovery Lifecycle disabled. Not starting");
}
} else {
if (!this.running.get()) {
this.context.publishEvent(new InstancePreRegisteredEvent(this, this.getRegistration()));
//主要看这个注册
this.register();
if (this.shouldRegisterManagement()) {
this.registerManagement();
}
this.context.publishEvent(new InstanceRegisteredEvent(this, this.getConfiguration()));
this.running.compareAndSet(false, true);
}
}
}
public void register(Registration registration) {
if (StringUtils.isEmpty(registration.getServiceId())) {
log.warn("No service to register for nacos client...");
return;
}
//nacos名字服务
NamingService namingService = namingService();
//注册服务id
String serviceId = registration.getServiceId();
//分组名
String group = nacosDiscoveryProperties.getGroup();
//当前实例信息
Instance instance = getNacosInstanceFromRegistration(registration);
try {
//注册实例
namingService.registerInstance(serviceId, group, instance);
log.info("nacos registry, {} {} {}:{} register finished", group, serviceId,
instance.getIp(), instance.getPort());
}
catch (Exception e) {
log.error("nacos registry, {} register failed...{},", serviceId,
registration.toString(), e);
// rethrow a RuntimeException if the registration is failed.
// issue : https://github.com/alibaba/spring-cloud-alibaba/issues/1132
rethrowRuntimeException(e);
}
}
public void registerInstance(String serviceName, String groupName, Instance instance) throws NacosException {
NamingUtils.checkInstanceIsLegal(instance);
String groupedServiceName = NamingUtils.getGroupedName(serviceName, groupName);
if (instance.isEphemeral()) {
//构建心跳
BeatInfo beatInfo = this.beatReactor.buildBeatInfo(groupedServiceName, instance);
//心跳执行器
this.beatReactor.addBeatInfo(groupedServiceName, beatInfo);
}
//注册服务
this.serverProxy.registerService(groupedServiceName, groupName, instance);
}
public void registerService(String serviceName, String groupName, Instance instance) throws NacosException {
LogUtils.NAMING_LOGGER.info("[REGISTER-SERVICE] {} registering service {} with instance: {}", new Object[]{this.namespaceId, serviceName, instance});
Map<String, String> params = new HashMap(16);
params.put("namespaceId", this.namespaceId);
params.put("serviceName", serviceName);
params.put("groupName", groupName);
params.put("clusterName", instance.getClusterName());
params.put("ip", instance.getIp());
params.put("port", String.valueOf(instance.getPort()));
params.put("weight", String.valueOf(instance.getWeight()));
params.put("enable", String.valueOf(instance.isEnabled()));
params.put("healthy", String.valueOf(instance.isHealthy()));
params.put("ephemeral", String.valueOf(instance.isEphemeral()));
params.put("metadata", JacksonUtils.toJson(instance.getMetadata()));
//这里就是给nacos服务端发送远程请求去注册(/nacos/v1/ns/instance)
this.reqApi(UtilAndComs.nacosUrlInstance, params, "POST");
}
服务注册(服务端)
根据刚刚服务端发起的注册地址/nacos/v1/ns/instance，我们在nacos源码找到对应的接口层 InstanceController#register(HttpServletRequest request)
public String register(HttpServletRequest request) throws Exception {
final String namespaceId = WebUtils
.optional(request, CommonParams.NAMESPACE_ID, Constants.DEFAULT_NAMESPACE_ID);
final String serviceName = WebUtils.required(request, CommonParams.SERVICE_NAME);
NamingUtils.checkServiceNameFormat(serviceName);
//从请求中解析实例
final Instance instance = parseInstance(request);
//注册实例
serviceManager.registerInstance(namespaceId, serviceName, instance);
return "ok";
}
public void registerInstance(String namespaceId, String serviceName, Instance instance) throws NacosException {
//当前服务第一次注册时,创建空的实例并未放置实例进去
createEmptyService(namespaceId, serviceName, instance.isEphemeral());
//从map中获取service
Service service = getService(namespaceId, serviceName);
if (service == null) {
throw new NacosException(NacosException.INVALID_PARAM,
"service not found, namespace: " + namespaceId + ", service: " + serviceName);
}
//新增实例（写时复制）
addInstance(namespaceId, serviceName, instance.isEphemeral(), instance);
}
private List<Instance> addIpAddresses(Service service, boolean ephemeral, Instance... ips) throws NacosException {
return updateIpAddresses(service, UtilsAndCommons.UPDATE_INSTANCE_ACTION_ADD, ephemeral, ips);
}
public List<Instance> updateIpAddresses(Service service, String action, boolean ephemeral, Instance... ips)
throws NacosException {
Datum datum = consistencyService
.get(KeyBuilder.buildInstanceListKey(service.getNamespaceId(), service.getName(), ephemeral));
//获取当前已注册的服务集群节点
List<Instance> currentIPs = service.allIPs(ephemeral);
Map<String, Instance> currentInstances = new HashMap<>(currentIPs.size());
Set<String> currentInstanceIds = Sets.newHashSet();
//将已注册的服务集群节点信息复制
for (Instance instance : currentIPs) {
currentInstances.put(instance.toIpAddr(), instance);
currentInstanceIds.add(instance.getInstanceId());
}
Map<String, Instance> instanceMap;
if (datum != null && null != datum.value) {
instanceMap = setValid(((Instances) datum.value).getInstanceList(), currentInstances);
} else {
instanceMap = new HashMap<>(ips.length);
}
for (Instance instance : ips) {
if (!service.getClusterMap().containsKey(instance.getClusterName())) {//判断要注册的实例属不属于
Cluster cluster = new Cluster(instance.getClusterName(), service);
cluster.init();
service.getClusterMap().put(instance.getClusterName(), cluster);
Loggers.SRV_LOG
.warn("cluster: {} not found, ip: {}, will create new cluster with default configuration.",
instance.getClusterName(), instance.toJson());
}
//移除掉节点
if (UtilsAndCommons.UPDATE_INSTANCE_ACTION_REMOVE.equals(action)) {
instanceMap.remove(instance.getDatumKey());
} else {
//判断当前实例是否已经注册过
Instance oldInstance = instanceMap.get(instance.getDatumKey());
if (oldInstance != null) {
//注册过
instance.setInstanceId(oldInstance.getInstanceId());
} else {
//未注册生成id
instance.setInstanceId(instance.generateInstanceId(currentInstanceIds));
}
//存放到临时map中
instanceMap.put(instance.getDatumKey(), instance);
}
}
if (instanceMap.size() <= 0 && UtilsAndCommons.UPDATE_INSTANCE_ACTION_ADD.equals(action)) {
throw new IllegalArgumentException(
"ip list can not be empty, service: " + service.getName() + ", ip list: " + JacksonUtils
.toJson(instanceMap.values()));
}
return new ArrayList<>(instanceMap.values());
}
