2023年4月21日-关于远程feign调用实现文件上传下载
一、客户需求：做一个查询程序，客户提供一个excel模板，将查询结果保存到excel模板中，上传到文件服务，供客户下载使用。
二、代码实现
// 服务A，文件上传
@ApiOperation("上传文件-demo")
@PostMapping(value = "/uploadDemo/{busType}/{billId}")
public ResBean uploadFile(@PathVariable("busType") String busType,
@PathVariable("billId") String billId,
@RequestParam(value = "file") MultipartFile file
) {
/**
......省略上传逻辑
*/
return null;
}
// 服务B，feign客户端
package com.xxxx.remote;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Repository;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;
@Repository
@FeignClient(name = "xxxxx")
public interface FeignClient {
@PostMapping(value = "/xxxx/xxxx/{busType}/{billId}"
, produces = {MediaType.APPLICATION_JSON_UTF8_VALUE}
, consumes = MediaType.MULTIPART_FORM_DATA_VALUE
)
ResBean uploadFile(@PathVariable("busType") String busType,
@PathVariable("billId") String billId,
@RequestPart("file") MultipartFile file
);
}
// 服务B，业务层
public ResBean optexcel() throws IOException {
List<UserEntity> dataList = new ArrayList<>();
for (int i = 0; i < 10; i++) {
UserEntity userEntity = new UserEntity();
userEntity.setName("张三" + i);
userEntity.setAge(20 + i);
userEntity.setTime(new Date(System.currentTimeMillis() + i));
dataList.add(userEntity);
}
//生成excel文档
Workbook workbook = ExcelExportUtil.exportExcel(new ExportParams("用户","用户信息"),
UserEntity.class, dataList);
MultipartFile file = workbookToCommonsMultipartFile(workbook, "用户.xls");
ResBean resbean = this.FeignClient.uploadFile(
"xxxxxx",
"111222333",
file
);
return resbean;
}
public static MultipartFile workbookToCommonsMultipartFile(Workbook workbook, String fileName) {
FileItemFactory factory = new DiskFileItemFactory(16, null);
FileItem fileItem = factory.createItem("file", "text/plain", true, fileName);
try {
OutputStream os = fileItem.getOutputStream();
workbook.write(os);
os.close();
MultipartFile multipartFile = new CommonsMultipartFile(fileItem);
return multipartFile;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
总结：
坑1：不加如下注解，
produces = {MediaType.APPLICATION_JSON_UTF8_VALUE}
consumes = MediaType.MULTIPART_FORM_DATA_VALUE
报错信息：
Current request is not a multipart request
坑2：不使用@RequestPart
报错信息：the request was rejected because no multipart boundary was found
坑3：workbookToCommonsMultipartFile中factory.createItem方法中，第一参数，要和@RequestPart注解中value值一致
不一致报错信息：
Required request part 'file' is not present
坑4：上传到服务器的excel重新下载后，打开时，会提示文件损坏
这时候需要给excel做一下授信，授信成功，就可以正常打开了。
授信操作参考：https://jingyan.baidu.com/article/c85b7a64a7337d413aac9555.html