Integrate FastDFS with Spring Boot for File Upload, Download, and Management

Client

Official Java client for FastDFS is hosted at https://github.com/happyfish100/fastdfs-client-java. A forked version (groupId com.github.secbr, artifactId fastdfs-client-plus, version 1.1.1-RELEASE) fixes naming, adds Maven Central publishing and improves exception handling.

Maven Dependency

<dependency>
    <groupId>com.github.secbr</groupId>
    <artifactId>fastdfs-client-plus</artifactId>
    <version>1.1.1-RELEASE</version>
</dependency>

Spring Boot web and Thymeleaf starters are also required:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>

Configuration

Copy fdfs_client.conf.sample from the client source to src/main/resources/fdfs_client.conf and adjust the parameters as needed:

# connection timeout (seconds)
connect_timeout = 60
# network timeout (seconds)
network_timeout = 60
charset = UTF-8
http.tracker_http_port = 8888
http.anti_steal_token = no
http.secret_key = 123456
tracker_server = 192.168.43.143:22122

The library also accepts a .properties file with the fastdfs. prefix; multiple tracker servers can be listed separated by commas.

Utility Classes

FastDFSFile

public class FastDFSFile {
    private String name;
    private byte[] content;
    private String ext;
    private String md5;
    private String author;
    // getters and setters omitted for brevity
}

FastDFSClient Initialization

private static final String CONF_FILE = "fastdfs.conf";
private static TrackerClient trackerClient;
private static TrackerServer trackerServer;
private static StorageServer storageServer;
private static StorageClient1 storageClient;

static {
    try {
        ClientGlobal.init(CONF_FILE);
        trackerClient = new TrackerClient();
        trackerServer = trackerClient.getTrackerServer();
        storageServer = null; // optional explicit IP configuration
        storageClient = new StorageClient1(trackerServer, storageServer);
        System.out.println("Init config: " + ClientGlobal.configInfo());
    } catch (Exception e) {
        logger.error("FastDFSClient init error", e);
    }
}

Upload Method

public static String[] upload(FastDFSFile file) {
    NameValuePair[] metaList = new NameValuePair[1];
    metaList[0] = new NameValuePair("author", file.getAuthor());
    String[] uploadResults = null;
    try {
        uploadResults = storageClient.uploadFile(file.getContent(), file.getExt(), metaList);
    } catch (Exception e) {
        logger.error("Upload error for file: " + file.getName(), e);
    }
    if (uploadResults == null && storageClient != null) {
        logger.error("Upload error, code: " + storageClient.getErrorCode());
    }
    return uploadResults;
}

Get File Info

public static FileInfo getFile(String groupName, String remoteFileName) {
    try {
        return storageClient.getFileInfo(groupName, remoteFileName);
    } catch (Exception e) {
        logger.error("Get file error", e);
    }
    return null;
}

Download File

public static InputStream downFile(String groupName, String remoteFileName) {
    try {
        byte[] fileBytes = storageClient.downloadFile(groupName, remoteFileName);
        return new ByteArrayInputStream(fileBytes);
    } catch (Exception e) {
        logger.error("Download error", e);
    }
    return null;
}

Delete File

public static void deleteFile(String groupName, String remoteFileName) throws Exception {
    storageClient.deleteFile(groupName, remoteFileName);
}

Controller Layer

Upload endpoint handling multipart file and redirecting to a result page:

@PostMapping("/upload")
public String singleFileUpload(@RequestParam("file") MultipartFile file,
                               RedirectAttributes redirectAttributes) {
    try {
        String path = saveFile(file);
        redirectAttributes.addFlashAttribute("message", "Upload successful");
        redirectAttributes.addFlashAttribute("path", "File URL: " + path);
    } catch (Exception e) {
        logger.error("upload file failed", e);
    }
    return "redirect:/result";
}

File‑saving logic that builds a FastDFSFile, uploads it, and returns the accessible URL:

private String saveFile(MultipartFile multipartFile) throws IOException {
    String fileName = multipartFile.getOriginalFilename();
    assert fileName != null;
    String ext = fileName.substring(fileName.lastIndexOf('.') + 1);
    FastDFSFile file = new FastDFSFile(fileName, multipartFile.getBytes(), ext);
    String[] fileAbsolutePath = FastDFSClient.upload(file);
    if (fileAbsolutePath == null) {
        logger.error("Upload failed, please retry");
        throw new RuntimeException("Upload failed");
    }
    return FastDFSClient.getTrackerUrl()
           + fileAbsolutePath[0] + "/" + fileAbsolutePath[1];
}

Running the Spring Boot application makes the upload page available; after a successful upload the returned URL can be opened in a browser to view the stored file.

Full source code for this integration: https://github.com/secbr/springboot-all/tree/master/springboot-fastdfs