org.springframework.cloud.netflix.eureka.CloudEurekaClient.java Source code

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Here is the source code for org.springframework.cloud.netflix.eureka.CloudEurekaClient.java

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/*
 * Copyright 2013-2015 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.cloud.netflix.eureka;

import java.lang.reflect.Field;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.atomic.AtomicReference;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.cloud.client.discovery.event.HeartbeatEvent;
import org.springframework.cloud.netflix.eureka.serviceregistry.EurekaServiceRegistry;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.util.ReflectionUtils;

import com.netflix.appinfo.ApplicationInfoManager;
import com.netflix.appinfo.InstanceInfo;
import com.netflix.appinfo.InstanceInfo.InstanceStatus;
import com.netflix.discovery.DiscoveryClient;
import com.netflix.discovery.EurekaClientConfig;
import com.netflix.discovery.shared.transport.EurekaHttpClient;

import lombok.extern.apachecommons.CommonsLog;

/**
 * Subclass of {@link DiscoveryClient} that sends a {@link HeartbeatEvent} when
 * {@link CloudEurekaClient#onCacheRefreshed()} is called.
 * @author Spencer Gibb
 */
@CommonsLog
public class CloudEurekaClient extends DiscoveryClient {
    private static final Log log = LogFactory.getLog(EurekaServiceRegistry.class);

    private final AtomicLong cacheRefreshedCount = new AtomicLong(0);

    private ApplicationEventPublisher publisher;
    private Field eurekaTransportField;
    private ApplicationInfoManager applicationInfoManager;
    private AtomicReference<EurekaHttpClient> eurekaHttpClient = new AtomicReference<>();

    public CloudEurekaClient(ApplicationInfoManager applicationInfoManager, EurekaClientConfig config,
            ApplicationEventPublisher publisher) {
        this(applicationInfoManager, config, null, publisher);
    }

    public CloudEurekaClient(ApplicationInfoManager applicationInfoManager, EurekaClientConfig config,
            DiscoveryClientOptionalArgs args, ApplicationEventPublisher publisher) {
        super(applicationInfoManager, config, args);
        this.applicationInfoManager = applicationInfoManager;
        this.publisher = publisher;
        this.eurekaTransportField = ReflectionUtils.findField(DiscoveryClient.class, "eurekaTransport");
        ReflectionUtils.makeAccessible(this.eurekaTransportField);
    }

    public ApplicationInfoManager getApplicationInfoManager() {
        return applicationInfoManager;
    }

    public void cancelOverrideStatus(InstanceInfo info) {
        getEurekaHttpClient().deleteStatusOverride(info.getAppName(), info.getId(), info);
    }

    EurekaHttpClient getEurekaHttpClient() {
        if (this.eurekaHttpClient.get() == null) {
            try {
                Object eurekaTransport = this.eurekaTransportField.get(this);
                Field registrationClientField = ReflectionUtils.findField(eurekaTransport.getClass(),
                        "registrationClient");
                ReflectionUtils.makeAccessible(registrationClientField);
                this.eurekaHttpClient.compareAndSet(null,
                        (EurekaHttpClient) registrationClientField.get(eurekaTransport));
            } catch (IllegalAccessException e) {
                log.error("error getting EurekaHttpClient", e);
            }
        }
        return this.eurekaHttpClient.get();
    }

    public void setStatus(InstanceStatus newStatus, InstanceInfo info) {
        getEurekaHttpClient().statusUpdate(info.getAppName(), info.getId(), newStatus, info);
    }

    @Override
    protected void onCacheRefreshed() {
        if (this.cacheRefreshedCount != null) { //might be called during construction and will be null
            long newCount = this.cacheRefreshedCount.incrementAndGet();
            log.trace("onCacheRefreshed called with count: " + newCount);
            this.publisher.publishEvent(new HeartbeatEvent(this, newCount));
        }
    }
}