分布式文件存储–FastDFS

上传交互过程

• 1. client询问tracker上传到的storage，不需要附加参数；
• 1. tracker返回一台可用的storage；
• 1. client直接和storage通讯完成文件上传。

下载交互过程

• 1. client询问tracker下载文件的storage，参数为文件标识（卷名和文件名）；
• 1. tracker返回一台可用的storage；
• 1. client直接和storage通讯完成文件下载。
• 需要说明的是，client为使用FastDFS服务的调用方，client也应该是一台服务器，它对tracker和storage的调用均为服务器间的调用。

java整合FastDFS

/**
 * FastDFS 文件存取Utils
 */
public class FastDFSClient {

    static {
        //从classpath下获取文件对象获取路径
        String path = new ClassPathResource("fdfs_client.conf").getPath();
        try {
            ClientGlobal.init(path);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 图片上传
     *
     * @param file
     * @return
     */
    public static String[] upload(FastDFSFile file) {
        try {
            TrackerClient trackerClient = new TrackerClient();
            TrackerServer trackerServer = trackerClient.getConnection();
            StorageClient storageClient = new StorageClient(trackerServer, null);
            //参数1 字节数组
            //参数2 扩展名(不带点)
            //参数3 元数据( 文件的大小,文件的作者,文件的创建时间戳)
            NameValuePair[] meta_list = new NameValuePair[]{new NameValuePair(file.getAuthor()), new NameValuePair(file.getName())};
            String[] strings = storageClient.upload_file(file.getContent(), file.getExt(), meta_list);
            // strings[0]==group1  strings[1]=M00/00/00/wKjThF1aW9CAOUJGAAClQrJOYvs424.jpg
            return strings;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 图片下载
     *
     * @param groupName
     * @param remoteFileName
     * @return
     */
    public static InputStream downFile(String groupName, String remoteFileName) {
        ByteArrayInputStream byteArrayInputStream = null;
        try {
            //3.创建trackerclient对象
            TrackerClient trackerClient = new TrackerClient();
            //4.创建trackerserver 对象
            TrackerServer trackerServer = trackerClient.getConnection();
            //5.创建stroageserver 对象
            //6.创建storageclient 对象
            StorageClient storageClient = new StorageClient(trackerServer, null);
            //7.根据组名 和 文件名 下载图片

            //参数1:指定组名
            //参数2 :指定远程的文件名
            byte[] bytes = storageClient.download_file(groupName, remoteFileName);
            byteArrayInputStream = new ByteArrayInputStream(bytes);
            return byteArrayInputStream;
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                if (byteArrayInputStream != null) {
                    byteArrayInputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return null;
    }

    /**
     * 图片删除
     *
     * @param groupName
     * @param remoteFileName
     */
    public static void deleteFile(String groupName, String remoteFileName) {
        try {
            //3.创建trackerclient对象
            TrackerClient trackerClient = new TrackerClient();
            //4.创建trackerserver 对象
            TrackerServer trackerServer = trackerClient.getConnection();
            //5.创建stroageserver 对象
            //6.创建storageclient 对象
            StorageClient storageClient = new StorageClient(trackerServer, null);
            int i = storageClient.delete_file(groupName, remoteFileName);
            if (i == 0) {
                System.out.println("删除成功");
            } else {
                System.out.println("删除失败");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 根据组名获取组的信息
     *
     * @param groupName
     * @return
     */
    public static StorageServer getStorages(String groupName) {
        try {
            TrackerClient trackerClient = new TrackerClient();
            //4.创建trackerserver 对象
            TrackerServer trackerServer = trackerClient.getConnection();

            //参数1 指定traqckerserver 对象
            //参数2 指定组名
            StorageServer group1 = trackerClient.getStoreStorage(trackerServer, groupName);
            return group1;
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 根据文件名和组名获取文件的信息
     *
     * @param groupName
     * @param remoteFileName
     * @return
     */
    public static FileInfo getFile(String groupName, String remoteFileName) {
        try {
            TrackerClient trackerClient = new TrackerClient();
            //4.创建trackerserver 对象
            TrackerServer trackerServer = trackerClient.getConnection();

            StorageClient storageClient = new StorageClient(trackerServer, null);

            //参数1 指定组名
            //参数2 指定文件的路径
            FileInfo fileInfo = storageClient.get_file_info(groupName, remoteFileName);
            return fileInfo;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 根据文件名和组名 获取组信息的数组信息
     *
     * @param groupName
     * @param remoteFileName
     * @return
     */
    public static ServerInfo[] getServerInfo(String groupName, String remoteFileName) {
        try {
            //3.创建trackerclient对象
            TrackerClient trackerClient = new TrackerClient();
            //4.创建trackerserver 对象
            TrackerServer trackerServer = trackerClient.getConnection();

            ServerInfo[] group1s = trackerClient.getFetchStorages(trackerServer, groupName, remoteFileName);
            return group1s;
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;

    }

    /**
     * 获取tracker 的ip和端口的信息,
     * http://192.168.211.132:8080
     *
     * @return
     */
    public static String getTrackerUrl() {
        try {
            //3.创建trackerclient对象
            TrackerClient trackerClient = new TrackerClient();
            //4.创建trackerserver 对象
            TrackerServer trackerServer = trackerClient.getConnection();
            //tracker 的ip的信息
            String hostString = trackerServer.getInetSocketAddress().getHostString();

            //http://192.168.211.132:8080/group1/M00/00/00/wKjThF1aW9CAOUJGAAClQrJOYvs424.jpg img
            int g_tracker_http_port = ClientGlobal.getG_tracker_http_port();
            return "http://" + hostString + ":" + g_tracker_http_port;
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }
}

FastDFSFile

fdfs_client.conf

Original: https://www.cnblogs.com/dw3306/p/14562312.html
Author: 邓维-java
Title: 分布式文件存储–FastDFS