cn.flood.cloud.gateway.rule.VersionGrayLoadBalancer Maven / Gradle / Ivy
package cn.flood.cloud.gateway.rule;
import cn.flood.Func;
import cn.flood.constants.HeaderConstants;
import cn.flood.lang.StringUtils;
import lombok.AllArgsConstructor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.cloud.gateway.support.NotFoundException;
import org.springframework.http.server.reactive.ServerHttpRequest;
import java.util.List;
import java.util.Map;
/**
* 基于客户端版本号灰度路由
*
* @author L.cm
* @author madi
* @date 2021-02-24 13:41
*/
@AllArgsConstructor
public class VersionGrayLoadBalancer implements GrayLoadBalancer {
private final Logger log = LoggerFactory.getLogger(this.getClass());
private DiscoveryClient discoveryClient;
/**
* 根据serviceId 筛选可用服务
*
* @param serviceId 服务ID
* @param request 当前请求
* @return
*/
@Override
public ServiceInstance choose(String serviceId, ServerHttpRequest request) {
List instances = discoveryClient.getInstances(serviceId);
//注册中心无实例 抛出异常
if (Func.isEmpty(instances)) {
log.warn("No instance available for {}", serviceId);
throw new NotFoundException("No instance available for " + serviceId);
}
// 获取请求version，无则随机返回可用实例
String reqVersion = request.getHeaders().getFirst(HeaderConstants.HEADER_VERSION);
if (Func.isBlank(reqVersion)) {
return instances.get(StringUtils.randomInt(instances.size()));
}
// 遍历可以实例元数据，若匹配则返回此实例
for (ServiceInstance instance : instances) {
Map metadata = instance.getMetadata();
String targetVersion = metadata.get("version");
if (reqVersion.equalsIgnoreCase(targetVersion)) {
log.debug("gray requst match success :{} {}", reqVersion, instance);
return instance;
}
}
return instances.get(StringUtils.randomInt(instances.size()));
}
}