实现图片上传与下载 - 采用分布式文件系统 - 可查看https://blog.csdn.net/qq_38225558/article/details/86511320

一、后端实现：

 中

1.导入依赖：

<dependency>
    <groupId>com.zhengqing</groupId>
    <artifactId>basic_util</artifactId>
    <version>1.0-SNAPSHOT</version>
</dependency>
<!--fastdfs依赖-->
<dependency>
    <groupId>org.csource.fastdfs</groupId>
    <artifactId>fastdfs</artifactId>
    <version>1.2</version>
</dependency>

2.配置文件：

3.工具类：

public class FastDfsApiOpr {
     
    public static String CONF_FILENAME  = FastDfsApiOpr.class.getClassLoader().getResource("fast_client.conf").getFile();

    /**
     * 上传文件
     */
    public static  String upload(byte[] file,String extName) {
        try {
            ClientGlobal.init(CONF_FILENAME);
            TrackerClient tracker = new TrackerClient();
            TrackerServer trackerServer = tracker.getConnection();
            StorageServer storageServer = null;
            StorageClient storageClient = new StorageClient(trackerServer, storageServer);
            NameValuePair nvp [] = new NameValuePair[]{
                    new NameValuePair("age", "18"),
                    new NameValuePair("sex", "male")
            };
            String fileIds[] = storageClient.upload_file(file,extName,nvp);
            System.out.println(fileIds.length);
            System.out.println("组名：" + fileIds[0]);
            System.out.println("路径: " + fileIds[1]);
            return  "/"+fileIds[0]+"/"+fileIds[1];
        } catch (Exception e) {
            e.printStackTrace();
            return  null;
        }
    }
    /**
     * 上传文件
     */
    public static  String upload(String path,String extName) {
        try { 
            ClientGlobal.init(CONF_FILENAME);
            TrackerClient tracker = new TrackerClient(); 
            TrackerServer trackerServer = tracker.getConnection(); 
            StorageServer storageServer = null;
            StorageClient storageClient = new StorageClient(trackerServer, storageServer);
            String fileIds[] = storageClient.upload_file(path, extName,null);
            System.out.println(fileIds.length); 
            System.out.println("组名：" + fileIds[0]); 
            System.out.println("路径: " + fileIds[1]);
            return  "/"+fileIds[0]+"/"+fileIds[1];
        } catch (Exception e) {
            e.printStackTrace();
            return  null;
        }
    }

    /**
     * 下载文件
     */
    public static byte[] download(String groupName,String fileName) {
        try {
            ClientGlobal.init(CONF_FILENAME);
            TrackerClient tracker = new TrackerClient(); 
            TrackerServer trackerServer = tracker.getConnection(); 
            StorageServer storageServer = null;
            StorageClient storageClient = new StorageClient(trackerServer, storageServer); 
            byte[] b = storageClient.download_file(groupName, fileName);
            return  b;
        } catch (Exception e) {
            e.printStackTrace();
            return  null;
        } 
    }

    /**
     * 删除文件
     */
    public static void delete(String groupName,String fileName){
        try { 
            ClientGlobal.init(CONF_FILENAME);
            TrackerClient tracker = new TrackerClient(); 
            TrackerServer trackerServer = tracker.getConnection(); 
            StorageServer storageServer = null;
            StorageClient storageClient = new StorageClient(trackerServer, storageServer); 
            int i = storageClient.delete_file(groupName,fileName);
            System.out.println( i==0 ? "删除成功" : "删除失败:"+i);
        } catch (Exception e) {
            e.printStackTrace();
            throw  new RuntimeException("删除异常,"+e.getMessage());
        } 
    }
}

3.编写controller代码：

/**
 * 上传和下载暂时只给外部页面之间调用 -》 不写feign
 */
@RestController
public class FastDfsController {

    @RequestMapping(value = "/upload",method = RequestMethod.POST)
    public AjaxResult upload(@RequestParam(value = "file",required = true) MultipartFile file){
        try {
            System.out.println(file.getOriginalFilename() + ":" + file.getSize());
            String originalFilename = file.getOriginalFilename();
            // xxx.jpg
            String extName = originalFilename.substring(originalFilename.lastIndexOf(".")+1);
            System.out.println(extName);
            String filePath =  FastDfsApiOpr.upload(file.getBytes(), extName);
            return AjaxResult.me().setResultObj(filePath);
        } catch (IOException e) {
            e.printStackTrace();
            return AjaxResult.me().setSuccess(false).setMessage("上传失败!"+e.getMessage());
        }
    }

    // /goup1/xxxxx/yyyy
    @RequestMapping(value = "/del",method = RequestMethod.DELETE)
    public AjaxResult upload(@RequestParam(value = "filePath",required = true)String filePath){
        String pathTmp = filePath.substring(1); // goup1/xxxxx/yyyy
        String groupName =  pathTmp.substring(0, pathTmp.indexOf("/")); //goup1
        String remotePath = pathTmp.substring(pathTmp.indexOf("/")+1);// xxxxx/yyyy
        System.out.println(groupName);
        System.out.println(remotePath);
        FastDfsApiOpr.delete(groupName, remotePath);
        return  AjaxResult.me();
    }
}

4.启动测试 

postman测试：

上传文件

检验是否成功：http://172.16.14.211/group1/M00/00/02/rBAO01w_ck-AAG02AAAdIsUcl40226.jpg

删除文件：

再刷新浏览器检查是否成功删除

二、前端实现：  代码部分略...

源码和文档：https://pan.baidu.com/s/1a6GNBSmP2H2y_VuZ9weySw