SpringCloud接收MultiPartFile文件 | HttpClient发送MultiPartFile请求到SpringCloud

首先，感谢作者 一缕82年的清风的文章，因为在使用HttpClient发送请求之前，我使用@requestPart注解，或者通过在@FeignClient中配置configuration都不行。接下来详细说说通过HttpClient发送请求的做法。

 

本地环境：eclipse+springboot+springcloud

本例使用的maven依赖：

!-- HttpClient -->
	    <dependency>
	        <groupId>commons-httpclient</groupId>
	        <artifactId>commons-httpclient</artifactId>
	        <version>3.1</version>
	        <type>pom</type>
	    </dependency>

1.新建HttpUtils工具类，内容如下：

package com.aspire.oms.util;

import java.io.IOException;
import java.nio.charset.Charset;
import java.util.Map;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.mime.HttpMultipartMode;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.springframework.web.multipart.MultipartFile;

/**
* @author rbrother
* @version 创建时间：2019年9月4日 下午10:35:37
* 类说明
*/

public class HttpUtils {
	
	/**
     * 使用httpclint 发送文件
     * @author: qingfeng
     * @date: 2019-05-27
     * @param url --> SpringCloud 对应方法的 @RequestMapping 内的映射地址
     * @file --> 上传的文件
     * @fileParamName --> SpringCloud 对应方法中的接收参数名，例如 void method(@RequestParam("file")MultiPartFIle file) ;中@RequestParam内的value值
     * @headParam --> http请求头信息
     * @otherParam 除了上传文件，有时候还要上传别的参数，把这些请求参数存入这个映射中
     * @return 响应结果
     */
    public static String uploadFile(String url ,MultipartFile file,String fileParamName,Map<String,String>headerParams,Map<String,String>otherParams) {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        String result = "";
        try {
            String fileName = file.getOriginalFilename();
            HttpPost httpPost = new HttpPost(url);
            //添加header
            for (Map.Entry<String, String> e : headerParams.entrySet()) {
                httpPost.addHeader(e.getKey(), e.getValue());
            }
            MultipartEntityBuilder builder = MultipartEntityBuilder.create();
            builder.setCharset(Charset.forName("utf-8"));
            builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);//加上此行代码解决返回中文乱码问题
            builder.addBinaryBody(fileParamName, file.getInputStream(), ContentType.MULTIPART_FORM_DATA, fileName);// 文件流
            for (Map.Entry<String, String> e : otherParams.entrySet()) {
                builder.addTextBody(e.getKey(), e.getValue());// 类似浏览器表单提交，对应input的name和value
            }
            HttpEntity entity = builder.build();
            httpPost.setEntity(entity);
            HttpResponse response = httpClient.execute(httpPost);// 执行提交
            HttpEntity responseEntity = response.getEntity();
            if (responseEntity != null) {
                // 将响应内容转换为字符串
                result = EntityUtils.toString(responseEntity, Charset.forName("UTF-8"));
            }
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                httpClient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return result;
    }
    
}

要注意，这种情况下，一旦对方返回的结果中存在中文有可能出现乱码，解决方法就是向上面的代码中加入：

builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);//加上此行代码解决返回中文乱码问题、

2.本地SpringBoot对应请求方法内容

/**
	 * 
	 * @param file 文件
	 * @return
	 */
	@SuppressWarnings("rawtypes")
	@RequestMapping(value = "test", method = RequestMethod.POST)
	public ServerResponse test(
			@RequestParam("file") MultipartFile file, @RequestParam("param1") String param1,
			@RequestParam("param2") String param2, @RequestParam("param3") String param3
			){
		
		String result = "" ;
		try {
			if(file != null) {
				String url = hostName + "springcloud中的@RequestMapping的value" ;
				String fileParamName = "file" ;
				Map<String, String> headerParams = new HashMap<>() ;
				Map<String, String> otherParams = new HashMap<>() ;
				otherParams.put("param1", param1) ;
				otherParams.put("param2", param2) ;
                otherParams.put("param3", param3) ;
				result = HttpUtils.uploadFile(url, file, fileParamName, headerParams, otherParams) ;
				System.out.println(result);
				
			}
			
		} catch (Exception e) {
			e.printStackTrace();
		}
		
		return null;
	}

3.SpringCloud接收方法：

 @RequestMapping(value = "/springcloud中的@RequestMapping的value", produces = "application/json;charset=UTF-8", method = RequestMethod.POST)
    public ServerResponse testResponse(@RequestParam("param1") String param1, @RequestParam("param2") String param2, @RequestParam("param3") String param3, @RequestParam("file") MultipartFile file) {
    //自己的判断逻辑        
}