SpringBoot访问FastDFS

1. 引入jar依赖

<parent>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-parent</artifactId>
  <version>2.0.5.RELEASE</version>
</parent>

<dependencies>
  <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
  </dependency>
  <dependency>
    <groupId>com.github.tobato</groupId>
    <artifactId>fastdfs-client</artifactId>
    <version>1.26.1-RELEASE</version>
  </dependency>
</dependencies>

2. 配置文件application.yml

fdfs:
  connectTimeout: 600
  trackerList:
    - 192.168.211.130:22122
    - 192.168.211.135:22122
    - 192.168.211.136:22122
server:
  port: 8899

3. 编写上传下载文件的服务类

package com.fastdfs.service;

import com.github.tobato.fastdfs.domain.StorePath;
import com.github.tobato.fastdfs.proto.storage.DownloadByteArray;
import com.github.tobato.fastdfs.service.FastFileStorageClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.io.ByteArrayInputStream;
import java.io.IOException;

@Component
public class FastDFSClientService {
  @Autowired
  private FastFileStorageClient fastFileStorageClient;
  /*
   * 文件上传
   *
   * @param bytes 文件字节
   * @param fileSize 文件大小
   * @param extension 文件扩展名
   * @return fastDfs路径
   */
  public String uploadFile(byte[] bytes, long fileSize, String extension) {
    ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(bytes);
    StorePath storePath = fastFileStorageClient.uploadFile(byteArrayInputStream, fileSize, extension, null);
    System.out.println(storePath.getGroup() + ":" + storePath.getPath() + ":" + storePath.getFullPath());
    return storePath.getFullPath();
  }

  /*
   * 下载文件
   *
   * @param fileUrl 文件URL
   * @return 文件字节
   * @throws IOException
   */
  public byte[] downloadFile(String fileUrl) throws IOException {
    String group = fileUrl.substring(0, fileUrl.indexOf("/"));
    String path = fileUrl.substring(fileUrl.indexOf("/") + 1);
    DownloadByteArray downloadByteArray = new DownloadByteArray();
    byte[] bytes = fastFileStorageClient.downloadFile(group, path, downloadByteArray);
    return bytes;
  }

}

4. 控制器类

package com.fastdfs.controller;

import com.fastdfs.service.FastDFSClientService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.net.URLEncoder;

@RestController
@RequestMapping("/fastdfs")
public class FastDFSController {
  @Autowired
  private FastDFSClientService fastDFSClientService;

  @RequestMapping("/upload")
  public String uploadFile(MultipartFile file) throws IOException {
    byte[] bytes = file.getBytes();
    String originalFileName = file.getOriginalFilename();
    String extension = originalFileName.substring(originalFileName.lastIndexOf(".") + 1);
    String fileName = file.getName();
    long fileSize = file.getSize();
    System.out.println(originalFileName + ":" + fileName + ":" + fileSize + ":" + extension + ":" + bytes.length);
    return fastDFSClientService.uploadFile(bytes, fileSize, extension);
  }

  @RequestMapping("/download")
  public void downloadFile(String fileUrl, HttpServletResponse response) throws IOException {
    byte[] bytes = fastDFSClientService.downloadFile(fileUrl);
    response.setHeader("Content-disposition", "attachment;filename=" + URLEncoder.encode(fileUrl, "UTF-8"));
    response.setCharacterEncoding("UTF-8");
    ServletOutputStream outputStream = null;
    try {
      outputStream = response.getOutputStream();
      outputStream.write(bytes);
    } catch (IOException e) {
      e.printStackTrace();
    } finally {
      try {
        outputStream.flush();
        outputStream.close();
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
  }

}

5. 编写启动类

package com.fastdfs;

import com.github.tobato.fastdfs.FdfsClientConfig;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.EnableMBeanExport;
import org.springframework.context.annotation.Import;
import org.springframework.jmx.support.RegistrationPolicy;

//解决jmx重复注册bean的问题
@EnableMBeanExport(registration = RegistrationPolicy.IGNORE_EXISTING)
//只需要一行注解就可以拥有带有连接池的FastDFS Java客户端了
@Import(FdfsClientConfig.class)
@SpringBootApplication
public class FastDfsApplicationMain {

  public static void main(String[] args) {
    SpringApplication.run(FastDfsApplicationMain.class, args);
  }
}

6. 使用postman 进行测试
   

业务场景

头像上传

nginx头像缩略图

处理思路:

• 上传图片时，直接处理成缩略图，不是很灵活，业务很确定可以使用
• 先存储图片，使用时，实时计算
  

附件

上传附件

下载附件
思考：是使用直接的url，还是需要写一个处理请求

避免重复

解决方案：
上传成功后计算文件对应的MD5然后存入MySQL，添加文件时把文件MD5和之前存入MYSQL中的存储的信息对比。
参考:DigestUtils.md5DigestAsHex(bytes)。