feign的使用注意

首先feign接口处和被调用的controller接口无法相同。

@FeignClient(name = ModuleConstant.ModuleName.API)
public interface ReportFileRemote {
    @GetMapping("/api/reportRemote/allAmByArea")
    @ApiOperation(value = "查询全校的区域的工作时段和非工作时段")
    List<Map<String, Object>> allAmByArea(@RequestParam("dateStart") String dateStart,@RequestParam("dateEnd") String dateEnd);
}

@Slf4j
@RestController
@RequestMapping("/api/reportRemote")
@Api("远程调用接口")
public class ReportFileRemoteController {
    @Autowired
    private AmMeterDataService amMeterDataService;
    @Autowired
    private PartmentService partmentService;
    @Autowired
    private ArchitectureService architectureService;
    @Autowired
    private DictionaryValueService dictionaryValueService;
    @Autowired
    private WaterMeterDataService waterMeterDataService;

    @GetMapping("/allAmByArea")
    @ApiOperation(value = "查询全校的区域的工作时段和非工作时段")
    public List<Map<String, Object>> allAmByArea( @RequestParam("dateStart") String  dateStart, @RequestParam("dateEnd") String dateEnd) {
        String[] start = dateStart.split("-");
        DateVo startDate = new DateVo(Integer.valueOf(start[0]), Integer.valueOf(start[1]), Integer.valueOf(start[2]));
        String[] end = dateEnd.split("-");
        DateVo endDate = new DateVo(Integer.valueOf(end[0]), Integer.valueOf(end[1]), Integer.valueOf(end[2]));
        List<Map<String, Object>> maps = amMeterDataService.allAreaGross1(null, null, null, startDate, endDate, null, null, null);
        return maps;
    }
}

1：如果controller的接口有@RequestParm制定了参数名称，那么feign那里也要加入这个注解的属性，并且名字也要取的相同。
2：feign处必须有@RequestParm注解（针对get请求），controller处不一定需要该注解
3：如果想使用get请求传输pojo对象，就使用@SpringQueryMap注解，这个注解会帮我们解析传入的对象的参数然后拼接到url(这里不懂等会讲原理)
4：@SpringQueryMap只能使用一次，使用多次，后面参数接收的值都是填充第一个参数的值。

image.png
image.png

传入的值为4月1号和4月22号，

image.png
实际debug发现接收的都是4.1号
5：pojo对象为简单对象，里面属性不能含有对象。
我测试过，封装一个对象

@Data
public calss DatesVo{
    private DateVo start;
    private DateVo end;
}
@Data
public class DateVo{
    private Integer year;
    private Integer month;
    private Integer date;
}

然后尝试将传入的参数改为@SpringQueryMap DatesVo datesVo,并不能解析复杂对象，因为feign的本质是对httpClientTemplate对象的封装，所以我们的url很难拼接一个复杂对象上去，或者无法解析复杂对象。
6：由于get的参数大小有限制，所以当传输的对象复杂时，推荐使用@RequestBody和post请求解决。

package com.sf.energy.nplatform.feign.module.datacenter;

import com.alibaba.fastjson.JSONObject;
import com.sf.energy.nplatform.common.constant.ModuleConstant;
import com.sf.energy.nplatform.common.entity.BaseMeterDataEntity;
import com.sf.energy.nplatform.common.entity.Result;
import com.sf.energy.nplatform.common.entity.StatDataEntity;
import com.sf.energy.nplatform.common.entity.query.MeterDataQueryEntity;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.cloud.openfeign.SpringQueryMap;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestParam;

import java.util.Date;
import java.util.List;

@FeignClient(name = ModuleConstant.ModuleName.DATACENTER)
public interface MeterDataServiceRemote {

    @GetMapping(value = "/datacenter/data/findByCondition")
    Result<List<JSONObject>> findByCondition(@SpringQueryMap MeterDataQueryEntity baseQueryEntity);

    @PostMapping(value = "/datacenter/data/save")
    Result save(@RequestBody BaseMeterDataEntity data);

    @PostMapping(value = "/datacenter/data/saveBatch")
    Result saveBatch(@RequestBody List<BaseMeterDataEntity> dataList);


    @PostMapping(value = "/datacenter/data/deleteData")
    Result deleteData(@RequestParam Long meterId, @RequestParam Integer meterType, @RequestParam Date startTime, @RequestParam Date endTime);

    @GetMapping(value = "/datacenter/data/getOneAtTime")
    Result<JSONObject> getOneAtTime(@RequestParam Long meterId, @RequestParam Date time, @RequestParam Integer meterType);


    @GetMapping(value = "/datacenter/data/getOneBeforeTime")
    Result<JSONObject> getOneBeforeTime(@RequestParam Long meterId, @RequestParam Date time, @RequestParam Integer meterType);


    @GetMapping(value = "/datacenter/data/getOneAfterTime")
    Result<JSONObject> getOneAfterTime(@RequestParam Long meterId, @RequestParam Date time, @RequestParam Integer meterType);

    @GetMapping(value = "/datacenter/data/getOneBetweenTime")
    Result<JSONObject> getOneBetweenTime(@RequestParam Long meterId, @RequestParam Integer meterType, @RequestParam Date startTime, @RequestParam Date endTime, @RequestParam String orderDirection);

    @GetMapping(value = "/datacenter/data/getTwoBeforeTime")
    Result<List<JSONObject>> getTwoBeforeTime(@RequestParam Long meterId, @RequestParam Date time, @RequestParam Integer meterType);


}