一、准备工作

安装好MongoDB

MongoDB Community Download | MongoDB

教程所用环境

SpringBoot~2.1.13
MongoDB~5.0.9
JDK11

二、上传视频到MongoDB

上传代码我这里就不写了，其他文章有很多参考

一、打开Navicat for MongoDB（没有此工具的可以去网上下载）

1、创建数据库后在数据库中新建存储桶

2、上传视频

三、配置SpringBoot

一、配置MongDB环境

1、导入相关maven包

<dependency>
       <groupId>cn.hutool</groupId>
       <artifactId>hutool-all</artifactId>
       <version>4.5.16</version>
</dependency>

<dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>

2、yml配置

spring:
  data:
    mongodb:
      host: 127.0.0.1
      port: 27017
      #数据库
      database: frontop_saas_file
      #验证库
      authentication-database: admin
      #用户（如果MongoDB没有配置授权验证的可以不用写验证信息）
      username: admin
      #密码
      password: admin

3、配置自定义GridFsTemplate和GridFSBucket的Bean

作用：如果不配置自定义的话GridFSBucket和GridFsTemplate的话，默认回去fs存储桶中寻找文件，而不是从我们自定义mp4的存储桶中寻找

新建GirdFsConfig.java

package com.frontop.system.config;

import com.mongodb.MongoClient;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.gridfs.GridFSBucket;
import com.mongodb.client.gridfs.GridFSBuckets;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.mongodb.MongoDbFactory;
import org.springframework.data.mongodb.core.convert.MongoConverter;
import org.springframework.data.mongodb.gridfs.GridFsTemplate;

/**
 * @author YangBoss
 * @title: GridFsConfig
 * @projectName frontop-ao
 * @description: TODO
 * @date 2022/6/22 17:08
 */

@Configuration
public class GridFsConfig {


    //获取配置文件中数据库信息
    @Value("${spring.data.mongodb.database}")
    String db;

    @Bean(name = "gridFsMp4Template")
    public GridFsTemplate gridFsTestTemplate(MongoDbFactory dbFactory, MongoConverter converter) {
        return new GridFsTemplate(dbFactory, converter, "mp4");
    }


    //GridFSBucket用于打开下载流
    @Bean(name="gridMp4BucketTemplate")
    public GridFSBucket getGridFSBucket(MongoClient mongoClient){
        MongoDatabase mongoDatabase = mongoClient.getDatabase(db);
        GridFSBucket bucket = GridFSBuckets.create(mongoDatabase,"mp4");
        return bucket;
    }
}

四、开始读取视频

1、创建接口，直接贴代码，视频做了分段，按每1024字节返回流

package com.frontop.system.modules.app.controller;

import com.frontop.common.annotation.AnonymousAccess;
import com.frontop.system.modules.app.model.FileDocument;
import com.frontop.system.modules.app.service.MongoFileService;
import com.mongodb.BasicDBObject;
import com.mongodb.DBObject;
import com.mongodb.client.gridfs.GridFSBucket;
import com.mongodb.client.gridfs.GridFSDownloadStream;
import com.mongodb.client.gridfs.model.GridFSFile;
import org.bson.types.ObjectId;
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.web.bind.annotation.*;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
/**
 * @author YangBoss
 * @title: RedioController
 * @projectName frontop-ao
 * @description: TODO
 * @date 2022/6/22 17:21
 */

@RestController
@RequestMapping("/video")
public class RedioController {
    @Resource(name = "gridFsMp4Template")
    private GridFsTemplate gridFsTestTemplate;
    @Resource(name = "gridMp4BucketTemplate")
    private GridFSBucket gridFSBucket;
    /**
     * 在线分段读取视频文件
     */
    @GetMapping("/viewTo/{id}")
    public void viewTo(HttpServletResponse response,HttpServletRequest request,@PathVariable("id") String id) throws Exception {
        long  skip = -1;
        long  length = -1;
        Query gridQuery = new Query().addCriteria(Criteria.where("_id").is(new ObjectId(id)));
        //根据id查询文件
        GridFSFile gridFSDBFile = gridFsTestTemplate.findOne(gridQuery);
        response.setHeader("Content-Type", "video/mp4");
        long fileLength = gridFSDBFile.getLength();
        long end = fileLength - 1;
        String range = request.getHeader("Range");
        if (range != null && range.length() > 0) {
            int idx = range.indexOf("-");
            skip = Long.parseLong(range.substring(6, idx));
            if ((idx + 1) < range.length()) {
                end = Long.parseLong(range.substring(idx + 1));
            }
            length = end - skip + 1;
        }

        if (range == null || range.length() <= 0) {//bytes=32523-32523
            response.setHeader("Content-Length", "" + fileLength);
            response.setStatus(200);
        } else {
            response.setHeader("Content-Length", "" + length);
            response.setHeader("Content-Range", "bytes " + skip + "-" + end + "/" + fileLength);
            response.setStatus(206);
        }
        System.out.println("bytes " + skip + "-" + end + "/" + fileLength);
        download(response.getOutputStream(), gridFSDBFile, skip, length);
    }

    /**
     * 文件下载基础类
     * 断点续读
     * @param outputStream 文件输出流
     * @param fsFile mongo文件
     * @param skip         跳过多少字节 <=0忽略
     * @param length       输出字节长度 <=忽略
     * @throws Exception
     */
    public void download(OutputStream outputStream, GridFSFile fsFile, long skip, long length) throws Exception {
        InputStream inputStream = null;
        try {
            //打开流下载对象
            GridFSDownloadStream in = gridFSBucket.openDownloadStream(fsFile.getObjectId());
            //获取流对象
            GridFsResource resource = new GridFsResource(fsFile, in);
            inputStream = resource.getInputStream();
            if (skip > 0) {
                inputStream.skip(skip);
            }
            byte[] bs = new byte[1024];
            int len;
            while ((len = inputStream.read(bs)) != -1) {
                if (length > 0) {
                    if (length > len) {
                        outputStream.write(bs, 0, len);
                        outputStream.flush();
                        length -= len;
                    } else {
                        outputStream.write(bs, 0, (int) length);
                        outputStream.flush();
                        break;
                    }
                } else {
                    outputStream.write(bs, 0, len);
                    outputStream.flush();
                }
            }
        } catch (Exception e) {
            throw e;
        } finally {
            if (inputStream != null) {
                inputStream.close();
            }
            if (outputStream != null) {
                outputStream.close();
            }
        }
    }


}