Feign的调用报错时，降级处理方式，fallBackFactory

Feign的调用报错时，降级处理fallBackFactory

项目结构：

代码：

remoteCdsService

package com.gsafety.framework.api;

import com.alibaba.fastjson.JSONObject;
import com.gsafety.framework.api.constant.ServiceNameConstants;
import com.gsafety.framework.api.factory.RemoteRcsFallbackFactory;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;

/**
 * @author wzx
 * @Description 公共资源服务
 * @Date 2022/8/19 10:48
 */
@FeignClient(contextId = "remoteRcsService", value = ServiceNameConstants.RCS_SERVICE, fallbackFactory = RemoteRcsFallbackFactory.class)
public interface RemoteRcsService {

    /**
     * 获取重复警情配置
     * @return
     */
    @GetMapping("/config/v1/getRepeatWarnRuleInfo")
    public JSONObject getRepeatWarnRuleInfo();
}

remoteCdsFallbackFactory

package com.gsafety.framework.api.factory;

import com.alibaba.fastjson.JSONObject;
import com.gsafety.framework.api.RemoteRcsService;
import feign.hystrix.FallbackFactory;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

/**
 * @author wzx
 * @Description 公共资源服务降级处理
 * @Date 2022/8/19 10:53
 */
@Component
public class RemoteRcsFallbackFactory implements FallbackFactory<RemoteRcsService> {

    private static final Logger log = LoggerFactory.getLogger(RemoteRcsFallbackFactory.class);

    @Override
    public RemoteRcsService create(Throwable throwable) {
        log.error("rcs服务失败:{}", throwable.getMessage());
        return new RemoteRcsService() {
            @Override
            public JSONObject getRepeatWarnRuleInfo() {
                return null;
            }

            @Override
            public JSONObject getDisposePlanListForOrganDispose(String warnType, String warnLevel, String zhId, String yhqk, Integer lc, String bkrs) {
                return null;
            }

            @Override
            public JSONObject queryListAddressBook() {
                return null;
            }

            @Override
            public JSONObject getAddressBooksByParentId(String itemParentId, String userId) {
                return null;
            }

            @Override
            public JSONObject queryAddressBookByIds(String ids) {
                return null;
            }

            @Override
            public JSONObject getParentSysDictDataDetail(String dictValue, String dictType) {
                return null;
            }

            @Override
            public JSONObject getDisposePlanListForWarnLevenUp(String warnType, String warnLevel, String zhId, String yhqk, Integer lc, String bkrs, String rswz, Integer rsmj) {
                return null;
            }

            @Override
            public JSONObject getImportantWarnNoticeList() {
                return null;
            }

            @Override
            public JSONObject getCarDutyRecord(String carNumber, String startTime, String endTime) {
                return null;
            }

            @Override
            public JSONObject getResImportantUnitByName(String name) {
                return null;
            }

            @Override
            public JSONObject addSysNoticeNew(String json) {
                return null;
            }
        };
    }
}

这样子在remoteCdsService接口里面调用报错的时候，就会转到RemoteCdsFallbackFactory里面的create方法进行自定义操作。

我这边是当报错的时候，接口直接返回Null.

Feign注解的contextId：

@FeignClient(contextId = "remoteCdsService", value = ServiceNameConstants.CDS_SERVICE, fallbackFactory = RemoteCdsFallbackFactory.class)

• contextId：用来唯一标识当一个微服务中存在多个FeignClient接口调用同一个服务提供者时的场景(若是不提供该属性值，则在程序启动时会启动失败，并提示如下信息

• ---

  APPLICATION FAILED TO START

  ---

  Description:

  The bean ‘service-provider8000.FeignClientSpecification’ could not be registered. A bean with that name has already been defined and overriding is disabled.

  Action:

n ‘service-provider8000.FeignClientSpecification’ could not be registered. A bean with that name has already been defined and overriding is disabled.

Action:

Consider renaming one of the beans or enabling overriding by setting spring.main.allow-bean-definition-overriding=true