SpringBoot 利用MongoDB存储图片文件

MongoDB 分片, 当你一台文件服务器硬盘不够的时候, 分片轻而易举解决这个问题

 大批量文件, 图片, 视频, 音频 考虑采用 MongoDB gridfs

package cn.tom.demo.controllerr;


import com.mongodb.client.MongoDatabase;
import com.mongodb.client.gridfs.GridFSBucket;
import com.mongodb.client.gridfs.GridFSBuckets;
import com.mongodb.client.gridfs.GridFSDownloadStream;
import com.mongodb.client.gridfs.model.GridFSFile;
import org.apache.tomcat.util.http.fileupload.IOUtils;
import org.bson.types.ObjectId;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.mongodb.MongoDbFactory;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.data.mongodb.gridfs.GridFsResource;
import org.springframework.data.mongodb.gridfs.GridFsTemplate;
import org.springframework.stereotype.Controller;
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.ResponseBody;
import org.springframework.web.multipart.MultipartFile;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;
import java.io.InputStream;



@Controller
@RequestMapping("/file")
public class FileController {
    // 获得SpringBoot提供的mongodb的GridFS对象
    @Autowired
    private GridFsTemplate gridFsTemplate;
    @Resource
    private MongoDbFactory mongoDbFactory;
    
    @RequestMapping(value = "/upload", method = RequestMethod.POST)
    @ResponseBody
    public String uploadFile(@RequestParam("file")MultipartFile multiportFile) throws Exception {

        String fileName = multiportFile.getOriginalFilename();
        // 获得文件输入流
        InputStream ins = multiportFile.getInputStream();
        // 获得文件类型
        String contentType = multiportFile.getContentType();
        // 将文件存储到mongodb中,mongodb 将会返回这个文件的具体信息
        ObjectId objectId = gridFsTemplate.store(ins, fileName, contentType);
        //将文件信息保存到关系型数据库中进行维护

        return "id===>" + objectId.toHexString(); //id 16进制字符串, 一定拿到
    }

    
    @RequestMapping(value = "/down")
    public void downloadFile(@RequestParam(name = "file_id") String fileId, HttpServletRequest request, HttpServletResponse response) throws Exception {
        System.out.println("Finding by ID: " + fileId);
        // fileId 16 进制字符串
        GridFSFile fsFile = gridFsTemplate.findOne(new Query(Criteria
                .where("_id").is(new ObjectId(fileId))));
        //打开下载流对象

        //获取数据库 demodb
        MongoDatabase db = mongoDbFactory.getDb();
        System.out.println("db===> " + db.getName());
        GridFSBucket gridFSBucket = GridFSBuckets.create(db);
        GridFSDownloadStream gridFSDownloadStream = gridFSBucket.openDownloadStream(fsFile.getObjectId());
        //创建GridFsResource用于获取流对象
        GridFsResource resource = new GridFsResource(fsFile, gridFSDownloadStream);
        
        String fileName = fsFile.getFilename().replace(",", "");
        //处理中文文件名乱码
        if (request.getHeader("User-Agent").toUpperCase().contains("MSIE") ||
                request.getHeader("User-Agent").toUpperCase().contains("TRIDENT")
                || request.getHeader("User-Agent").toUpperCase().contains("EDGE")) {
            fileName = java.net.URLEncoder.encode(fileName, "UTF-8");
        } else {
            //非IE浏览器的处理：
            fileName = new String(fileName.getBytes("UTF-8"), "ISO-8859-1");
        }
        // 通知浏览器进行文件下载
        response.setContentType("multipart/form-data");
        response.setHeader("Content-Disposition", "attachment;filename="" + fileName + """);
        IOUtils.copy(resource.getInputStream(), response.getOutputStream());
    }

    
    @RequestMapping(value = "/remove")
    @ResponseBody
    public String  deleteFile(@RequestParam(name = "file_id") String fileId) {
        Query query = Query.query(Criteria.where("_id").is(fileId));
        // 查询单个文件
        GridFSFile gfsfile = gridFsTemplate.findOne(query);

        gridFsTemplate.delete(query);
        return "删除==>" + gfsfile.getFilename();
    }

}

   ObjectId objectId = gridFsTemplate.store(ins, fileName, contentType);
   //将文件信息保存到关系型数据库中进行维护
   
  这个值需要保存在 产品表中对应的文件的图片的 id
   String  fileId= objectId.toHexString();    //转成 16 进制的字符串
   
   如果用的 mysql 数据库也是如此, 也是如此
   这样你的 mysql 就保存交易数据, 描述性的数据就在 MongoDB