监听服务是否存在

  <dependency>
            <groupId>de.codecentric</groupId>
            <artifactId>spring-boot-admin-starter-server</artifactId>
            <version>2.2.3</version>
        </dependency>

import de.codecentric.boot.admin.server.domain.entities.Instance;
import de.codecentric.boot.admin.server.domain.entities.InstanceRepository;
import de.codecentric.boot.admin.server.domain.events.InstanceEvent;
import de.codecentric.boot.admin.server.domain.events.InstanceStatusChangedEvent;
import de.codecentric.boot.admin.server.notify.AbstractStatusChangeNotifier;
import reactor.core.publisher.Mono;

public class DingdingNotifier extends AbstractStatusChangeNotifier {
    public DingdingNotifier(InstanceRepository repository) {
        super(repository);
    }

    @Override
    protected boolean shouldNotify(InstanceEvent event, Instance instance) {
        if (event instanceof InstanceStatusChangedEvent) {
            return true;
        }
        return false;
    }

    @Override
    protected Mono<Void> doNotify(InstanceEvent event, Instance instance) {
        return Mono.fromRunnable(() -> {
//                    createMessage(event, instance);
                }

        );
    }
}

import cn.jiguang.anti.deception.monitor.notifier.DingTalkNotifier;
import de.codecentric.boot.admin.server.config.AdminServerHazelcastAutoConfiguration;
import de.codecentric.boot.admin.server.config.AdminServerNotifierAutoConfiguration;
import de.codecentric.boot.admin.server.domain.entities.InstanceRepository;
import org.springframework.boot.autoconfigure.AutoConfigureBefore;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * @author yintp
 */
@Configuration
@ConditionalOnProperty(
        prefix = "spring.boot.admin.notify.dingtalk",
        name = {"webhook-token"}
)
@AutoConfigureBefore({AdminServerHazelcastAutoConfiguration.NotifierTriggerConfiguration.class, AdminServerNotifierAutoConfiguration.CompositeNotifierConfiguration.class})
public class DingTalkNotifierConfiguration {
    @Bean
    @ConditionalOnMissingBean
    @ConfigurationProperties(prefix = "spring.boot.admin.notify.dingtalk")
    public DingTalkNotifier dingTalkNotifier(InstanceRepository repository) {
        return new DingTalkNotifier(repository);
    }
}