使用Spring Boot集成FastDFS的示例代码

这篇文章我们介绍如何使用Spring Boot将文件上传到分布式文件系统FastDFS中。

这个项目会在上一个项目的基础上进行构建。

1、pom包配置

我们使用Spring Boot最新版本1.5.9、jdk使用1.8、tomcat8.0。

<dependency>
  <groupId>org.csource</groupId>
  <artifactId>fastdfs-client-java</artifactId>
  <version>1.27-SNAPSHOT</version>
</dependency>

加入了fastdfs-client-java包，用来调用FastDFS相关的API。

2、配置文件

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 = 192.168.53.85:22122
tracker_server = 192.168.53.86:22122

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

3、封装FastDFS上传工具类

封装FastDFSFile，文件基础信息包括文件名、内容、文件类型、作者等。

public class FastDFSFile {
  private String name;
  private byte[] content;
  private String ext;
  private String md5;
  private String author;
  //省略getter、setter

封装FastDFSClient类，包含常用的上传、下载、删除等方法。

首先在类加载的时候读取相应的配置信息，并进行初始化。

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

文件上传

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;
  try {
    storageClient = new StorageClient(trackerServer, storageServer);
    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) {
    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;
}

使用FastDFS提供的客户端storageClient来进行文件上传，最后将上传结果返回。

根据groupName和文件名获取文件信息。

public static FileInfo getFile(String groupName, String remoteFileName) {
  try {
    storageClient = new StorageClient(trackerServer, storageServer);
    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;
}

下载文件

public static InputStream downFile(String groupName, String remoteFileName) {
  try {
    storageClient = new StorageClient(trackerServer, storageServer);
    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;
}

删除文件

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

使用FastDFS时，直接调用FastDFSClient对应的方法即可。

4、编写上传控制类

从MultipartFile中读取文件信息，然后使用FastDFSClient将文件上传到FastDFS集群中。

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;
}

请求控制，调用上面方法saveFile()。

@PostMapping("/upload") //new annotation since 4.3
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";
}

上传成功之后，将文件的路径展示到页面，效果图如下：

在浏览器中访问此Url，可以看到成功通过FastDFS展示：

这样使用Spring Boot 集成FastDFS的案例就完成了。

示例代码-github

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