使用feign传递参数类型为MultipartFile的问题

feign传递参数类型为MultipartFile

feign默认是不支持多媒体文件类型的文件传输的，但是可以通过引入第三方jar包解决这个问题，步骤可以分为三步。

引入maven依赖

        <dependency>
            <groupId>io.github.openfeign.form</groupId>
            <artifactId>feign-form</artifactId>
            <version>3.3.0</version>
        </dependency>
        <dependency>
            <groupId>io.github.openfeign.form</groupId>
            <artifactId>feign-form-spring</artifactId>
            <version>3.3.0</version>
        </dependency>

加入配置类

@Configuration
public class FeignMultipartSupportConfig {
 
    @Bean
    @Primary
    @Scope("prototype")
    public Encoder multipartFormEncoder() {
        return new SpringFormEncoder();
    }
 
    @Bean
    public feign.Logger.Level multipartLoggerLevel() {
        return feign.Logger.Level.FULL;
    }
}

在feign客户端进行配置

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RequestPart;
import org.springframework.web.multipart.MultipartFile;
import config.FeignMultipartSupportConfig;
import feign.Response;
@FeignClient(value = "", fallback = FileServiceFallback.class,configuration=FeignMultipartSupportConfig.class)
public interface IFileService {
    //上传文件
    @RequestMapping(value = "/rmi/fileService/mediaImgUpload",  produces = {MediaType.APPLICATION_JSON_UTF8_VALUE},consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
    public String mediaImgUpload(@RequestPart MultipartFile file);
    //下载文件
    @RequestMapping(value = "/rmi/fileService/mediaDownload",method = RequestMethod.GET,consumes = MediaType.APPLICATION_JSON_UTF8_VALUE)
    public Response mediaDownload(@RequestParam(required = true) String mediaId);

feign传参MultipartFile问题解决

首先，feign服务之间的调用，传参默认的格式为：ContentType=application/x-www-form-urlencoded

以表单的形式传参的，而文件流的传参，需要form-data的ContentType，否则会报错的

首先引入依赖

 <dependency>
          <groupId>io.github.openfeign.form</groupId>
          <artifactId>feign-form</artifactId>
          <version>3.8.0</version>
      </dependency>

      <dependency>
          <groupId>io.github.openfeign.form</groupId>
          <artifactId>feign-form-spring</artifactId>
          <version>3.8.0</version>
      </dependency>

注意spring boot版本是2.x以上的，上面两个依赖的版本不低于3.5.0，否则还是无效的

新建feign的配置

package com.wm.blog_config.config; 
import feign.codec.Encoder;
import feign.form.spring.SpringFormEncoder;
import org.springframework.beans.factory.ObjectFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.http.HttpMessageConverters;
import org.springframework.cloud.openfeign.support.SpringEncoder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration; 

/**
* @author ：半卷流年
* @description : 解决feign传递流数据的异常
* @createTime ：2020/6/14
*/
@Configuration
public class FeignSupportConfig {

  @Autowired
  private ObjectFactory<HttpMessageConverters> messageConverters;

  @Bean
  public Encoder feignFormEncoder() {
      return new SpringFormEncoder(new SpringEncoder(messageConverters));
  } 
}

在feign接口中配置

package com.wm.blog_admin.feign; 
import com.wm.blog_admin.feign.factory.PictureClientFallbackFactory;
import com.wm.blog_common.constatnt.CommonConstant;
import com.wm.blog_common.domain.TFileDO;
import com.wm.blog_common.entity.TFile;
import com.wm.blog_common.req.TFileQuery;
import com.wm.blog_common.result.Result;
import com.wm.blog_config.config.CustomFeignConfig;
import com.wm.blog_config.config.FeignSupportConfig;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile; 
import java.util.List;

/***
* @ClassName: PictureFeignClient
* @Description: picture feign调用  todo feign使用get有坑啊,是否考虑使用HttpClient替换feign的HttpURLConnection，采用apache的HttpClient
* @Author: wm_yu
* @Create_time: 16:39 2020-3-26
*/
@FeignClient(value = CommonConstant.PICTURE_MODULE_NAME, configuration = {CustomFeignConfig.class, FeignSupportConfig.class}, fallbackFactory = PictureClientFallbackFactory.class)
public interface PictureFeignClient {

  /**
   * id查询图片信息
   * @param id
   * @return
   */
  @GetMapping("/web/picture/{id}")
  Result<TFileDO> get(@PathVariable("id") Long id); 

  /**
   * id批量查询图片信息
   * @param idList
   * @return
   */
  @PostMapping("/web/picture/getByIdList")
  Result<List<TFile>> getByIdList(@RequestBody List<Long> idList); 

  /**
   * 文件上传
   * @param file
   * @return
   */
  @PostMapping(value = "/web/picture/uploadFile",produces = {MediaType.APPLICATION_JSON_UTF8_VALUE},consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
   Result<String> uploadFile(@RequestPart("file") MultipartFile file); 
}

注意加上这个，表示传参格式：

就可以传参了的

以上为个人经验，希望能给大家一个参考，也希望大家多多支持编程教程。

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