SpringBoot整合FastDFS

FastDFS

FastDFS是一个开源的轻量级分布式文件系统，它对文件进行管理，功能包括：文件存储、文件同步、文件访问（文件上传、文件下载）等，解决了大容量存储和负载均衡的问题。特别适合以文件为载体的在线服务，如相册网站、视频网站等等。

FastDFS是纯C语言实现，只支持Linux、FreeBSD等UNIX系统。

FastDFS的两个核心概念分别是：Tracker（跟踪器）、Storage（存储节点）

跟踪器Tracker主要做调度工作，相当于mvc中的controller的角色，在访问上起负载均衡的作用。跟踪器和存储节点都可以由一台或多台服务器构成，跟踪器和存储节点中的服务器均可以随时增加或下线而不会影响线上服务，其中跟踪器中的所有服务器都是对等的，可以根据服务器的压力情况随时增加或减少。跟踪器Tracker负责管理所有的Storage和group，每个Storage在启动后会连接Tracker，告知自己所属的group等信息，并保持周期性的心跳，tracker根据storage的心跳信息，建立group==>[storage server list]的映射表，Tracker需要管理的元信息很少，会全部存储在内存中；另外tracker上的元信息都是由storage汇报的信息生成的，本身不需要持久化任何数据，这样使得tracker非常容易扩展，直接增加tracker机器即可扩展为tracker cluster来服务，cluster里每个tracker之间是完全对等的，所有的tracker都接受stroage的心跳信息，生成元数据信息来提供读写服务。

存储节点Storage采用了分卷[Volume]（或分组[group]）的组织方式，存储系统由一个或多个组组成，组与组之间的文件是相互独立的，所有组的文件容量累加就是整个存储系统中的文件容量。 一个卷[Volume]（组[group]）可以由一台或多台存储服务器组成，一个组中的存储服务器中的文件都是相同的，组中的多台存储服务器起到了冗余备份和负载均衡的作用，数据互为备份，存储空间以group内容量最小的storage为准，所以建议group内的多个storage尽量配置相同，以免造成存储空间的浪费。

Docker安装FastDFS

拉取镜像

 docker pull morunchang/fastdfs

查看镜像

运行tracker

docker run -d --name tracker --net=host morunchang/fastdfs sh tracker.sh

运行storage

docker run -d --name storage --net=host -e TRACKER_IP=<your tracker server address>:22122 -e GROUP_NAME=<group name> morunchang/fastdfs sh storage.sh

 is the tracker server's host
 is the storage server's group name

使用Spring Boot集成FastDFS

新建一个springboot项目，在pom文件加入fastdfs-client-java包，用来调用FastDFS相关的API

        <dependency>
            <groupId>org.csourcegroupId>
            <artifactId>fastdfs-client-javaartifactId>
            <version>1.27-SNAPSHOTversion>
        dependency>

resources目录下添加fdfs_client.conf文件

connect_timeout = 60
network_timeout = 60
charset = UTF-8
http.tracker_http_port = 8080
http.anti_steal_token = no
http.secret_key = 123456

tracker_server = 182.254.161.54:22122

配置文件设置了连接的超时时间，编码格式以及tracker_server地址等信息

详细内容参考：fastdfs-client-java

封装FastDFS上传工具类

public class FastDFSClient {
    private static org.slf4j.Logger logger = LoggerFactory.getLogger(FastDFSClient.class);

    static {
        try {
            String filePath = new ClassPathResource("fdfs_client.conf").getFile().getAbsolutePath();;
            ClientGlobal.init(filePath);
        } catch (Exception e) {
            logger.error("FastDFS Client Init Fail!",e);
        }
    }

    public static String[] upload(FastDFSFile file) {
        logger.info("File Name: " + file.getName() + "File Length:" + file.getContent().length);

        NameValuePair[] meta_list = new NameValuePair[1];
        meta_list[0] = new NameValuePair("author", file.getAuthor());

        long startTime = System.currentTimeMillis();
        String[] uploadResults = null;
        StorageClient storageClient=null;
        try {
            storageClient = getTrackerClient();
            uploadResults = storageClient.upload_file(file.getContent(), file.getExt(), meta_list);
        } catch (IOException e) {
            logger.error("IO Exception when uploadind the file:" + file.getName(), e);
        } catch (Exception e) {
            logger.error("Non IO Exception when uploadind the file:" + file.getName(), e);
        }
        logger.info("upload_file time used:" + (System.currentTimeMillis() - startTime) + " ms");

        if (uploadResults == null && storageClient!=null) {
            logger.error("upload file fail, error code:" + storageClient.getErrorCode());
        }
        String groupName = uploadResults[0];
        String remoteFileName = uploadResults[1];

        logger.info("upload file successfully!!!" + "group_name:" + groupName + ", remoteFileName:" + " " + remoteFileName);
        return uploadResults;
    }

    public static FileInfo getFile(String groupName, String remoteFileName) {
        try {
            StorageClient storageClient = getTrackerClient();
            return storageClient.get_file_info(groupName, remoteFileName);
        } catch (IOException e) {
            logger.error("IO Exception: Get File from Fast DFS failed", e);
        } catch (Exception e) {
            logger.error("Non IO Exception: Get File from Fast DFS failed", e);
        }
        return null;
    }

    public static InputStream downFile(String groupName, String remoteFileName) {
        try {
            StorageClient storageClient = getTrackerClient();
            byte[] fileByte = storageClient.download_file(groupName, remoteFileName);
            InputStream ins = new ByteArrayInputStream(fileByte);
            return ins;
        } catch (IOException e) {
            logger.error("IO Exception: Get File from Fast DFS failed", e);
        } catch (Exception e) {
            logger.error("Non IO Exception: Get File from Fast DFS failed", e);
        }
        return null;
    }

    public static void deleteFile(String groupName, String remoteFileName)
            throws Exception {
        StorageClient storageClient = getTrackerClient();
        int i = storageClient.delete_file(groupName, remoteFileName);
        logger.info("delete file successfully!!!" + i);
    }

    public static StorageServer[] getStoreStorages(String groupName)
            throws IOException {
        TrackerClient trackerClient = new TrackerClient();
        TrackerServer trackerServer = trackerClient.getConnection();
        return trackerClient.getStoreStorages(trackerServer, groupName);
    }

    public static ServerInfo[] getFetchStorages(String groupName,
                                                String remoteFileName) throws IOException {
        TrackerClient trackerClient = new TrackerClient();
        TrackerServer trackerServer = trackerClient.getConnection();
        return trackerClient.getFetchStorages(trackerServer, groupName, remoteFileName);
    }

    public static String getTrackerUrl() throws IOException {
        return "http://"+getTrackerServer().getInetSocketAddress().getHostString()+":"+ ClientGlobal.getG_tracker_http_port()+"/";
    }

    private static StorageClient getTrackerClient() throws IOException {
        TrackerServer trackerServer = getTrackerServer();
        StorageClient storageClient = new StorageClient(trackerServer, null);
        return  storageClient;
    }

    private static TrackerServer getTrackerServer() throws IOException {
        TrackerClient trackerClient = new TrackerClient();
        TrackerServer trackerServer = trackerClient.getConnection();
        return  trackerServer;
    }
}

编写Controller

@Controller
public class UploadController {
    private static Logger logger = LoggerFactory.getLogger(UploadController.class);

    @GetMapping("/")
    public String index() {
        return "upload";
    }

    @PostMapping("/upload")
    public String singleFileUpload(@RequestParam("file") MultipartFile file,
                                   RedirectAttributes redirectAttributes) {
        if (file.isEmpty()) {
            redirectAttributes.addFlashAttribute("message", "Please select a file to upload");
            return "redirect:uploadStatus";
        }
        try {
            // Get the file and save it somewhere
            String path=saveFile(file);
            redirectAttributes.addFlashAttribute("message",
                    "You successfully uploaded '" + file.getOriginalFilename() + "'");
            redirectAttributes.addFlashAttribute("path",
                    "file path url '" + path + "'");
        } catch (Exception e) {
            logger.error("upload file failed",e);
        }
        return "redirect:/uploadStatus";
    }

    @GetMapping("/uploadStatus")
    public String uploadStatus() {
        return "uploadStatus";
    }

    /**
     * @param multipartFile
     * @return
     * @throws IOException
     */
    public String saveFile(MultipartFile multipartFile) throws IOException {
        String[] fileAbsolutePath={};
        String fileName=multipartFile.getOriginalFilename();
        String ext = fileName.substring(fileName.lastIndexOf(".") + 1);
        byte[] file_buff = null;
        InputStream inputStream=multipartFile.getInputStream();
        if(inputStream!=null){
            int len1 = inputStream.available();
            file_buff = new byte[len1];
            inputStream.read(file_buff);
        }
        inputStream.close();
        FastDFSFile file = new FastDFSFile(fileName, file_buff, ext);
        try {
            fileAbsolutePath = FastDFSClient.upload(file);  //upload to fastdfs
        } catch (Exception e) {
            logger.error("upload file Exception!",e);
        }
        if (fileAbsolutePath==null) {
            logger.error("upload file failed,please upload again!");
        }
        String path=FastDFSClient.getTrackerUrl()+fileAbsolutePath[0]+ "/"+fileAbsolutePath[1];
        return path;
    }
}

运行：

访问FastDFS图片服务器，看看图片是否已经上传上去

看看docker里的FastDFS图片服务器是否存在rBAAC1s8dJSAYdR2AABj_N15NvY165.jpg

资料参考来源：
https://hub.docker.com/r/morunchang/fastdfs/
微笑大神代码讲得更好：http://www.ityouknow.com/springboot/2018/01/16/spring-boot-fastdfs.html