SpringDocConfiguration

import com.alibaba.nacos.client.naming.event.InstancesChangeEvent;
import com.alibaba.nacos.common.notify.Event;
import com.alibaba.nacos.common.notify.NotifyCenter;
import com.alibaba.nacos.common.notify.listener.Subscriber;
import com.alibaba.nacos.common.utils.StringUtils;
import lombok.RequiredArgsConstructor;
import org.springdoc.core.AbstractSwaggerUiConfigProperties;
import org.springdoc.core.SwaggerUiConfigProperties;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.context.annotation.Configuration;
import java.util.Set;
import java.util.stream.Collectors;


@Configuration(proxyBeanMethods = false)
@RequiredArgsConstructor
@ConditionalOnProperty(name = "springdoc.api-docs.enabled", matchIfMissing = true)
public class SpringDocConfiguration implements InitializingBean {

   private final SwaggerUiConfigProperties swaggerUiConfigProperties;

   private final DiscoveryClient discoveryClient;

   /**
    * 在初始化后调用的方法，用于注册SwaggerDocRegister订阅器
    */
   @Override
   public void afterPropertiesSet() {
      SwaggerDocRegister swaggerDocRegister = new SwaggerDocRegister(swaggerUiConfigProperties, discoveryClient);
      // 手动调用一次，避免监听事件掉线问题
      swaggerDocRegister.onEvent(null);
      NotifyCenter.registerSubscriber(swaggerDocRegister);
   }

}

/**
 * Swagger文档注册器，继承自Subscriber<InstancesChangeEvent>
 */
@RequiredArgsConstructor
class SwaggerDocRegister extends Subscriber<InstancesChangeEvent> {

   private final SwaggerUiConfigProperties swaggerUiConfigProperties;

   private final DiscoveryClient discoveryClient;

   /**
    * 事件回调方法，处理InstancesChangeEvent事件
    * @param event 事件对象
    */
   @Override
   public void onEvent(InstancesChangeEvent event) {
      Set<AbstractSwaggerUiConfigProperties.SwaggerUrl> swaggerUrlSet = discoveryClient.getServices()
         .stream()
         .flatMap(serviceId -> discoveryClient.getInstances(serviceId).stream())
         .filter(instance -> StringUtils.isNotBlank(instance.getMetadata().get("spring-doc")))
         .map(instance -> {
            AbstractSwaggerUiConfigProperties.SwaggerUrl swaggerUrl = new AbstractSwaggerUiConfigProperties.SwaggerUrl();
            swaggerUrl.setName(instance.getServiceId());
            swaggerUrl.setUrl(String.format("/%s/v3/api-docs", instance.getMetadata().get("spring-doc")));
            return swaggerUrl;
         })
         .collect(Collectors.toSet());

      swaggerUiConfigProperties.setUrls(swaggerUrlSet);
   }

   /**
    * 订阅类型方法，返回订阅的事件类型
    * @return 订阅的事件类型
    */
   @Override
   public Class<? extends Event> subscribeType() {
      return InstancesChangeEvent.class;
   }

}