springboot+vue前后端分离视频上传遇到的坑

最近在学习一个springboot+vue的一个项目，里面有个视频上传的功能。前段使用element ui中的upload组件

<el-form-item label="上传视频">
        <el-upload 
            name="file"
            :on-success="handleVideoUploadSuccess"
            :on-remove="handleVideoRemove"
            :before-remove="beforeVideoRemove"
            :on-exceed="handleUploadExceed"
            :file-list="fileList"
            :action="BASE_API+'/education_video/fileVideo/upload'"
            :limit="1"
            class="upload-demo">
            <el-button style="small" type="primary">上传视频</el-button>
            <el-tooltip placement="right-end">
                <div slot="content">最大支持1G<br>

                </div>
                <i class="el-icon-question"/>
            </el-tooltip>
        </el-upload>    
    </el-form-item>

BASE_API是在js中定义的一个变量

BASE_API: process.env.BASE_API, // 接口API地址

后端代码：

import com.juhaowl.commom.ResponseResult;
import com.juhaowl.video.service.VideoService;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;


/**
 * Created by Park on 2020-6-16.
 */
@RestController
@RequestMapping("/education_video/fileVideo")
@Api(value = "上传视频")
@CrossOrigin
public class VideoController {

    @Autowired
    VideoService videoService;

    @ApiOperation(value = "视频上传")
    @PostMapping(value = "upload")
    public ResponseResult uploadVideoFile(MultipartFile file){
        String videoId = videoService.uploadVideo(file);
        return ResponseResult.success().data("videoId",videoId);
    }
}

问题报错：
Access to XMLHttpRequest at 'http://localhost:9001/education_video/fileVideo/upload' from origin 'http://localhost:9528' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

看到这个问题，第一想法就是跨域问题，然后检查各种涉及跨域的问题，也没发现哪里问题。最终经过B站小伙伴的指导，终于找到问题所在。

导致这个问题的原因竟然是nginx配置文件里面没有配置 client_max_body_size 1024m 

 记录下自己曾经趟过的坑  也希望能对其他小伙伴有些帮助