SpringCloud微服务实战——搭建企业级开发框架（二十九）：集成分布式对象存储服务

  微服务应用中图片、文件等存储区别于单体应用，单体应用可以放到本地读写磁盘文件，微服务应用必需用到分布式存储，将图片、文件等存储到服务稳定的分布式存储服务器。目前，很多云服务商提供了存储的云服务，比如华为云等，另外还有开源对象存储服务器，比如FastDFS、MinIO等。
  如果我们的框架只支持一种存储服务，那么在后期扩展或者修改时会有局限性，所以，这里希望能够定义一个抽象接口，想使用哪种服务就实现哪种服务，在配置多个服务时，调用的存储时可以进行选择。
  首先，在框架搭建前，我们先准备环境，这里以MinIO为例，MinIO的安装十分简单，我们这里选择Linux安装包的方式来安装，具体方式参考：http://docs.minio.org.cn/docs/ 。

一、基础底层库实现

1. 在GitEgg-Platform中新建gitegg-platform-dfs (dfs: Distributed File System分布式文件系统)子工程用于定义对象存储服务的抽象接口，新建IDfsBaseService用于定义文件上传下载常用接口

/**
 * 分布式文件存储操作接口定义
 * 为了保留系统操作记录，原则上不允许上传文件物理删除，修改等操作。
 * 业务操作的修改删除文件，只是关联关系的修改，重新上传文件后并与业务关联即可。
 */
public interface IDfsBaseService {

    /**
     * 获取简单上传凭证
     * @param bucket
     * @return
     */
    String uploadToken(String bucket);


    /**
     * 获取覆盖上传凭证
     * @param bucket
     * @return
     */
    String uploadToken(String bucket, String key);

    /**
     * 创建 bucket
     * @param bucket
     */
    void createBucket(String bucket);

    /**
     * 通过流上传文件，指定文件名
     * @param inputStream
     * @param fileName
     * @return
     */
    GitEggDfsFile uploadFile(InputStream inputStream, String fileName);

    /**
     * 通过流上传文件，指定文件名和bucket
     * @param inputStream
     * @param bucket
     * @param fileName
     * @return
     */
    GitEggDfsFile uploadFile(InputStream inputStream, String bucket, String fileName);


    /**
     * 通过文件名获取文件访问链接
     * @param fileName
     * @return
     */
    String getFileUrl(String fileName);

    /**
     * 通过文件名和bucket获取文件访问链接
     * @param fileName
     * @param bucket
     * @return
     */
    String getFileUrl(String bucket, String fileName);

    /**
     * 通过文件名和bucket获取文件访问链接,设置有效期
     * @param bucket
     * @param fileName
     * @param duration
     * @param unit
     * @return
     */
    String getFileUrl(String bucket, String fileName, int duration, TimeUnit unit);

    /**
     * 通过文件名以流的形式下载一个对象
     * @param fileName
     * @return
     */
    OutputStream getFileObject(String fileName, OutputStream outputStream);

    /**
     * 通过文件名和bucket以流的形式下载一个对象
     * @param fileName
     * @param bucket
     * @return
     */
    OutputStream getFileObject(String bucket, String fileName, OutputStream outputStream);

    /**
     * 根据文件名删除文件
     * @param fileName
     */
    String removeFile(String fileName);

    /**
     * 根据文件名删除指定bucket下的文件
     * @param bucket
     * @param fileName
     */
    String removeFile(String bucket, String fileName);


    /**
     * 根据文件名列表批量删除文件
     * @param fileNames
     */
    String removeFiles(List<String> fileNames);

    /**
     * 根据文件名列表批量删除bucket下的文件
     * @param bucket
     * @param fileNames
     */
    String removeFiles(String bucket, List<String> fileNames);
}

2. 在GitEgg-Platform中新建gitegg-platform-dfs-minio子工程，新建MinioDfsServiceImpl和MinioDfsProperties用于实现IDfsBaseService文件上传下载接口

@Data
@Component
@ConfigurationProperties(prefix = "dfs.minio")
public class MinioDfsProperties {

    /**
     * AccessKey
     */
    private String accessKey;

    /**
     * SecretKey
     */
    private String secretKey;

    /**
     * 区域，需要在MinIO配置服务器的物理位置，默认是us-east-1（美国东区1）,这也是亚马逊S3的默认区域。
     */
    private String region;

    /**
     * Bucket
     */
    private String bucket;

    /**
     * 公开还是私有
     */
    private Integer accessControl;

    /**
     * 上传服务器域名地址
     */
    private String uploadUrl;

    /**
     * 文件请求地址前缀
     */
    private String accessUrlPrefix;

    /**
     *  上传文件夹前缀
     */
    private String uploadDirPrefix;
}

3. 在GitEgg-Platform中新建gitegg-platform-dfs-qiniu子工程，新建QiNiuDfsServiceImpl和QiNiuDfsProperties用于实现IDfsBaseService文件上传下载接口

@Data
@Component
@ConfigurationProperties(prefix = "dfs.qiniu")
public class QiNiuDfsProperties {


    /**
     * AccessKey
     */
    private String accessKey;

    /**
     * SecretKey
     */
    private String secretKey;

    /**
     * 云存储机房
     */
    private String region;

    /**
     * Bucket 存储块
     */
    private String bucket;

    /**
     * 公开还是私有
     */
    private Integer accessControl;

    /**
     * 上传服务器域名地址
     */
    private String uploadUrl;

    /**
     * 文件请求地址前缀
     */
    private String accessUrlPrefix;

    /**
     * 上传文件夹前缀
     */
    private String uploadDirPrefix;
}

4. 在GitEgg-Platform中新建gitegg-platform-dfs-starter子工程，用于集成所有文件上传下载子工程，方便业务统一引入所有实现

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>GitEgg-Platform</artifactId>
        <groupId>com.gitegg.platform</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>gitegg-platform-dfs-starter</artifactId>
    <name>${project.artifactId}</name>
    <packaging>jar</packaging>

    <dependencies>
        <!-- gitegg 分布式文件自定义扩展-minio -->
        <dependency>
            <groupId>com.gitegg.platform</groupId>
            <artifactId>gitegg-platform-dfs-minio</artifactId>
        </dependency>
        <!-- gitegg 分布式文件自定义扩展-云存储 -->
        <dependency>
            <groupId>com.gitegg.platform</groupId>
            <artifactId>gitegg-platform-dfs-qiniu</artifactId>
        </dependency>
    </dependencies>
</project>

5. gitegg-platform-bom中添加文件存储相关依赖

            <!-- gitegg 分布式文件自定义扩展 -->
            <dependency>
                <groupId>com.gitegg.platform</groupId>
                <artifactId>gitegg-platform-dfs</artifactId>
                <version>${gitegg.project.version}</version>
            </dependency>
            <!-- gitegg 分布式文件自定义扩展-minio -->
            <dependency>
                <groupId>com.gitegg.platform</groupId>
                <artifactId>gitegg-platform-dfs-minio</artifactId>
                <version>${gitegg.project.version}</version>
            </dependency>
            <!-- gitegg 分布式文件自定义扩展-云存储 -->
            <dependency>
                <groupId>com.gitegg.platform</groupId>
                <artifactId>gitegg-platform-dfs-qiniu</artifactId>
                <version>${gitegg.project.version}</version>
            </dependency>
            <!-- gitegg 分布式文件自定义扩展-starter -->
            <dependency>
                <groupId>com.gitegg.platform</groupId>
                <artifactId>gitegg-platform-dfs-starter</artifactId>
                <version>${gitegg.project.version}</version>
            </dependency>

           <!-- minio文件存储服务 https://mvnrepository.com/artifact/io.minio/minio -->
            <dependency>
                <groupId>io.minio</groupId>
                <artifactId>minio</artifactId>
                <version>${dfs.minio.version}</version>
            </dependency>
            <!--云存储文件存储服务-->
            <dependency>
                <groupId>com.qiniu</groupId>
                <artifactId>qiniu-java-sdk</artifactId>
                <version>${dfs.qiniu.version}</version>
            </dependency>

二、业务功能实现

分布式文件存储功能作为系统扩展功能放在gitegg-service-extension工程中，首先需要分为几个模块：

• 文件服务器的基本配置模块
• 文件的上传、下载记录模块(下载只记录私有文件，对于公共可访问的文件不需要记录)
• 前端访问下载实现

1. 新建文件服务器配置表，用于存放文件服务器相关配置，定义好表结构，使用代码生成工具生成增删改查代码。

CREATE TABLE `t_sys_dfs`  (
  `id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '主键',
  `tenant_id` bigint(20) NOT NULL DEFAULT 0 COMMENT '租户id',
  `dfs_type` bigint(20) NULL DEFAULT NULL COMMENT '分布式存储分类',
  `dfs_code` varchar(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '分布式存储编号',
  `access_url_prefix` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '文件访问地址前缀',
  `upload_url` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '分布式存储上传地址',
  `bucket` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '空间名称',
  `app_id` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '应用ID',
  `region` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '区域',
  `access_key` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT 'accessKey',
  `secret_key` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT 'secretKey',
  `dfs_default` tinyint(2) NOT NULL DEFAULT 0 COMMENT '是否默认存储 0否，1是',
  `dfs_status` tinyint(2) NOT NULL DEFAULT 1 COMMENT '状态 0禁用，1 启用',
  `access_control` tinyint(2) NOT NULL DEFAULT 0 COMMENT '访问控制 0私有，1公开',
  `comments` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '备注',
  `create_time` datetime(0) NULL DEFAULT NULL COMMENT '创建时间',
  `creator` bigint(20) NULL DEFAULT NULL COMMENT '创建者',
  `update_time` datetime(0) NULL DEFAULT NULL COMMENT '更新时间',
  `operator` bigint(20) NULL DEFAULT NULL COMMENT '更新者',
  `del_flag` tinyint(2) NULL DEFAULT 0 COMMENT '1:删除 0:不删除',
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 1 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci COMMENT = '分布式存储配置表' ROW_FORMAT = DYNAMIC;

2. 新建DfsQiniuFactory和DfsMinioFactory接口实现工厂类，用于根据当前用户的选择，实例化需要的接口实现类

/**
 * 云存储上传服务接口工厂类
 */
public class DfsQiniuFactory {

    public static IDfsBaseService getDfsBaseService(DfsDTO dfsDTO) {
        Auth auth = Auth.create(dfsDTO.getAccessKey(), dfsDTO.getSecretKey());
        Configuration cfg = new Configuration(Region.autoRegion());
        UploadManager uploadManager = new UploadManager(cfg);
        BucketManager bucketManager = new BucketManager(auth, cfg);
        QiNiuDfsProperties qiNiuDfsProperties = new QiNiuDfsProperties();
        qiNiuDfsProperties.setAccessKey(dfsDTO.getAccessKey());
        qiNiuDfsProperties.setSecretKey(dfsDTO.getSecretKey());
        qiNiuDfsProperties.setRegion(dfsDTO.getRegion());
        qiNiuDfsProperties.setBucket(dfsDTO.getBucket());
        qiNiuDfsProperties.setUploadUrl(dfsDTO.getUploadUrl());
        qiNiuDfsProperties.setAccessUrlPrefix(dfsDTO.getAccessUrlPrefix());
        qiNiuDfsProperties.setAccessControl(dfsDTO.getAccessControl());
        return new QiNiuDfsServiceImpl(auth, uploadManager, bucketManager, qiNiuDfsProperties);
    }
}

/**
 * MINIO上传服务接口工厂类
 */
public class DfsMinioFactory {

    public static IDfsBaseService getDfsBaseService(DfsDTO dfsDTO) {
        MinioClient minioClient =
                MinioClient.builder()
                        .endpoint(dfsDTO.getUploadUrl())
                        .credentials(dfsDTO.getAccessKey(), dfsDTO.getSecretKey()).build();;
        MinioDfsProperties minioDfsProperties = new MinioDfsProperties();
        minioDfsProperties.setAccessKey(dfsDTO.getAccessKey());
        minioDfsProperties.setSecretKey(dfsDTO.getSecretKey());
        minioDfsProperties.setRegion(dfsDTO.getRegion());
        minioDfsProperties.setBucket(dfsDTO.getBucket());
        minioDfsProperties.setUploadUrl(dfsDTO.getUploadUrl());
        minioDfsProperties.setAccessUrlPrefix(dfsDTO.getAccessUrlPrefix());
        minioDfsProperties.setAccessControl(dfsDTO.getAccessControl());

        return new MinioDfsServiceImpl(minioClient, minioDfsProperties);
    }
}

3. 新建DfsFactory工厂类，添加@Component使用容器管理该类（默认单例），用于根据系统用户配置，生成及缓存对应的上传下载接口实现

/**
 * DfsFactory工厂类,根据系统用户配置，生成及缓存对应的上传下载接口实现
 */
@Component
public class DfsFactory {

    /**
     * DfsService 缓存
     */
    private final static Map<Long, IDfsBaseService> dfsBaseServiceMap = new ConcurrentHashMap<>();

    /**
     * 获取 DfsService
     *
     * @param dfsDTO 分布式存储配置
     * @return dfsService
     */
    public IDfsBaseService getDfsBaseService(DfsDTO dfsDTO) {
        //根据dfsId获取对应的分布式存储服务接口，dfsId是唯一的，每个租户有其自有的dfsId
        Long dfsId = dfsDTO.getId();
        IDfsBaseService dfsBaseService = dfsBaseServiceMap.get(dfsId);
        if (null == dfsBaseService) {
            Class cls = null;
            try {
                cls = Class.forName(DfsFactoryClassEnum.getValue(String.valueOf(dfsDTO.getDfsType())));
                Method staticMethod = cls.getDeclaredMethod(DfsConstants.DFS_SERVICE_FUNCTION, DfsDTO.class);
                dfsBaseService = (IDfsBaseService) staticMethod.invoke(cls, dfsDTO);
                dfsBaseServiceMap.put(dfsId, dfsBaseService);
            } catch (ClassNotFoundException | NoSuchMethodException e) {
                e.printStackTrace();
            } catch (IllegalAccessException e) {
                e.printStackTrace();
            } catch (InvocationTargetException e) {
                e.printStackTrace();
            }
        }
        return dfsBaseService;
    }
}

4. 新建枚举类DfsFactoryClassEnum，用于DfsFactory 工厂类通过反射实例化对应文件服务器的接口实现类

/**
 * @ClassName: DfsFactoryClassEnum
 * @Description: 分布式存储工厂类枚举 ，因dfs表存的是数据字典表的id，这里省一次数据库查询，所以就用数据字典的id
 * @author GitEgg
 * @date 2020年09月19日 下午11:49:45
 */
public enum DfsFactoryClassEnum {

    /**
     * MINIO MINIO
     */
    MINIO("2", "com.gitegg.service.extension.dfs.factory.DfsMinioFactory"),

    /**
     * 云存储Kodo QINIUYUN_KODO
     */
    QI_NIU("3", "com.gitegg.service.extension.dfs.factory.DfsQiniuFactory"),

    /**
     * 阿里云OSS ALIYUN_OSS
     */
    ALI_YUN("4", "com.gitegg.service.extension.dfs.factory.DfsAliyunFactory"),

    /**
     * 腾讯云COS TENCENT_COS
     */
    TENCENT("5", "com.gitegg.service.extension.dfs.factory.DfsTencentFactory");

    public String code;

    public String value;

    DfsFactoryClassEnum(String code, String value) {
        this.code = code;
        this.value = value;
    }

    public static String getValue(String code) {
        DfsFactoryClassEnum[] smsFactoryClassEnums = values();
        for (DfsFactoryClassEnum smsFactoryClassEnum : smsFactoryClassEnums) {
            if (smsFactoryClassEnum.getCode().equals(code)) {
                return smsFactoryClassEnum.getValue();
            }
        }
        return null;
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public String getValue() {
        return value;
    }

    public void setValue(String value) {
        this.value = value;
    }
}

5. 新建IGitEggDfsService接口，用于定义业务需要的文件上传下载接口

/**
 * 业务文件上传下载接口实现
 *
 */
public interface IGitEggDfsService {


    /**
     * 获取文件上传的 token
     * @param dfsCode
     * @return
     */
    String uploadToken(String dfsCode);


    /**
     * 上传文件
     *
     * @param dfsCode
     * @param file
     * @return
     */
    GitEggDfsFile uploadFile(String dfsCode, MultipartFile file);

    /**
     * 获取文件访问链接
     * @param dfsCode
     * @param fileName
     * @return
     */
    String getFileUrl(String dfsCode, String fileName);


    /**
     * 下载文件
     * @param dfsCode
     * @param fileName
     * @return
     */
    OutputStream downloadFile(String dfsCode, String fileName, OutputStream outputStream);
}

6. 新建IGitEggDfsService接口实现类GitEggDfsServiceImpl，用于实现业务需要的文件上传下载接口

@Slf4j
@Service
@RequiredArgsConstructor(onConstructor_ = @Autowired)
public class GitEggDfsServiceImpl implements IGitEggDfsService {

    private final DfsFactory dfsFactory;

    private final IDfsService dfsService;

    private final IDfsFileService dfsFileService;

    @Override
    public String uploadToken(String dfsCode) {
        QueryDfsDTO queryDfsDTO = new QueryDfsDTO();
        queryDfsDTO.setDfsCode(dfsCode);
        DfsDTO dfsDTO = dfsService.queryDfs(queryDfsDTO);
        IDfsBaseService dfsBaseService = dfsFactory.getDfsBaseService(dfsDTO);
        String token = dfsBaseService.uploadToken(dfsDTO.getBucket());
        return token;
    }

    @Override
    public GitEggDfsFile uploadFile(String dfsCode, MultipartFile file) {
        QueryDfsDTO queryDfsDTO = new QueryDfsDTO();
        DfsDTO dfsDTO = null;

        // 如果上传时没有选择存储方式，那么取默认存储方式
        if(StringUtils.isEmpty(dfsCode)) {
            queryDfsDTO.setDfsDefault(GitEggConstant.ENABLE);
        }
        else {
            queryDfsDTO.setDfsCode(dfsCode);
        }

        GitEggDfsFile gitEggDfsFile = null;
        DfsFile dfsFile = new DfsFile();
        try {

            dfsDTO = dfsService.queryDfs(queryDfsDTO);

            IDfsBaseService dfsFileService = dfsFactory.getDfsBaseService(dfsDTO);

            //获取文件名
            String originalName = file.getOriginalFilename();
            //获取文件后缀
            String extension = FilenameUtils.getExtension(originalName);
            String hash = Etag.stream(file.getInputStream(), file.getSize());
            String fileName = hash + "." + extension;

            // 保存文件上传记录
            dfsFile.setDfsId(dfsDTO.getId());
            dfsFile.setOriginalName(originalName);
            dfsFile.setFileName(fileName);
            dfsFile.setFileExtension(extension);
            dfsFile.setFileSize(file.getSize());
            dfsFile.setFileStatus(GitEggConstant.ENABLE);

            //执行文件上传操作
            gitEggDfsFile = dfsFileService.uploadFile(file.getInputStream(), fileName);

            if (gitEggDfsFile != null)
            {
                gitEggDfsFile.setFileName(originalName);
                gitEggDfsFile.setKey(hash);
                gitEggDfsFile.setHash(hash);
                gitEggDfsFile.setFileSize(file.getSize());
            }

            dfsFile.setAccessUrl(gitEggDfsFile.getFileUrl());
        } catch (IOException e) {
            log.error("文件上传失败：{}", e);
            dfsFile.setFileStatus(GitEggConstant.DISABLE);
            dfsFile.setComments(String.valueOf(e));
        } finally {
            dfsFileService.save(dfsFile);
        }

        return gitEggDfsFile;
    }

    @Override
    public String getFileUrl(String dfsCode, String fileName) {
        String fileUrl = null;

        QueryDfsDTO queryDfsDTO = new QueryDfsDTO();
        DfsDTO dfsDTO = null;
        // 如果上传时没有选择存储方式，那么取默认存储方式
        if(StringUtils.isEmpty(dfsCode)) {
            queryDfsDTO.setDfsDefault(GitEggConstant.ENABLE);
        }
        else {
            queryDfsDTO.setDfsCode(dfsCode);
        }

        try {
            dfsDTO = dfsService.queryDfs(queryDfsDTO);
            IDfsBaseService dfsFileService = dfsFactory.getDfsBaseService(dfsDTO);
            fileUrl = dfsFileService.getFileUrl(fileName);
        }
        catch (Exception e)
        {
            log.error("文件上传失败：{}", e);
        }
        return fileUrl;
    }

    @Override
    public OutputStream downloadFile(String dfsCode, String fileName, OutputStream outputStream) {
        QueryDfsDTO queryDfsDTO = new QueryDfsDTO();
        DfsDTO dfsDTO = null;
        // 如果上传时没有选择存储方式，那么取默认存储方式
        if(StringUtils.isEmpty(dfsCode)) {
            queryDfsDTO.setDfsDefault(GitEggConstant.ENABLE);
        }
        else {
            queryDfsDTO.setDfsCode(dfsCode);
        }

        try {
            dfsDTO = dfsService.queryDfs(queryDfsDTO);
            IDfsBaseService dfsFileService = dfsFactory.getDfsBaseService(dfsDTO);
            outputStream = dfsFileService.getFileObject(fileName, outputStream);
        }
        catch (Exception e)
        {
            log.error("文件上传失败：{}", e);
        }
        return outputStream;
    }
}

7. 新建GitEggDfsController用于文件上传下载通用访问控制器

@RestController
@RequestMapping("/extension")
@RequiredArgsConstructor(onConstructor_ = @Autowired)
@Api(value = "GitEggDfsController|文件上传前端控制器")
@RefreshScope
public class GitEggDfsController {

    private final IGitEggDfsService gitEggDfsService;

    /**
     * 上传文件
     * @param uploadFile
     * @param dfsCode
     * @return
     */
    @PostMapping("/upload/file")
    public Result<?> uploadFile(@RequestParam("uploadFile") MultipartFile[] uploadFile, String dfsCode) {
        GitEggDfsFile gitEggDfsFile = null;
        if (ArrayUtils.isNotEmpty(uploadFile))
        {
            for (MultipartFile file : uploadFile) {
                gitEggDfsFile = gitEggDfsService.uploadFile(dfsCode, file);
            }
        }
        return Result.data(gitEggDfsFile);
    }


    /**
     * 通过文件名获取文件访问链接
     */
    @GetMapping("/get/file/url")
    @ApiOperation(value = "查询分布式存储配置表详情")
    public Result<?> query(String dfsCode, String fileName) {
        String fileUrl = gitEggDfsService.getFileUrl(dfsCode, fileName);
        return Result.data(fileUrl);
    }

    /**
     * 通过文件名以文件流的方式下载文件
     */
    @GetMapping("/get/file/download")
    public void downloadFile(HttpServletResponse response,HttpServletRequest request,String dfsCode, String fileName) {
        if (fileName != null) {
            response.setCharacterEncoding(request.getCharacterEncoding());
            response.setContentType("application/octet-stream");
            response.addHeader("Content-Disposition", "attachment;fileName=" + fileName);
            OutputStream os = null;
            try {
                os = response.getOutputStream();
                os = gitEggDfsService.downloadFile(dfsCode, fileName, os);
                os.flush();
                os.close();
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (os != null) {
                    try {
                        os.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
    }
}

8. 前端上传下载实现，注意的是：axios请求下载文件流时，需要设置 responseType: ‘blob’

• 上传

            handleUploadTest (row) {
                this.fileList = []
                this.uploading = false
                this.uploadForm.dfsType = row.dfsType
                this.uploadForm.dfsCode = row.dfsCode
                this.uploadForm.uploadFile = null
                this.dialogTestUploadVisible = true
            },
            handleRemove (file) {
                const index = this.fileList.indexOf(file)
                const newFileList = this.fileList.slice()
                newFileList.splice(index, 1)
                this.fileList = newFileList
            },
            beforeUpload (file) {
                this.fileList = [...this.fileList, file]
                return false
            },
            handleUpload () {
                this.uploadedFileName = ''
                const { fileList } = this
                const formData = new FormData()
                formData.append('dfsCode', this.uploadForm.dfsCode)
                fileList.forEach(file => {
                  formData.append('uploadFile', file)
                })
                this.uploading = true
                dfsUpload(formData).then(() => {
                    this.fileList = []
                    this.uploading = false
                    this.$message.success('上传成功')
                }).catch(err => {
                  console.log('uploading', err)
                  this.$message.error('上传失败')
                })
            }

• 下载

            getFileUrl (row) {
                this.listLoading = true
                this.fileDownload.dfsCode = row.dfsCode
                this.fileDownload.fileName = row.fileName
                dfsGetFileUrl(this.fileDownload).then(response => {
                    window.open(response.data)
                    this.listLoading = false
                })
            },
            downLoadFile (row) {
                this.listLoading = true
                this.fileDownload.dfsCode = row.dfsCode
                this.fileDownload.fileName = row.fileName
                this.fileDownload.responseType = 'blob'
                dfsDownloadFileUrl(this.fileDownload).then(response => {
                    const blob = new Blob([response.data])
                    var fileName = row.originalName
                    const elink = document.createElement('a')
                    elink.download = fileName
                    elink.style.display = 'none'
                    elink.href = URL.createObjectURL(blob)
                    document.body.appendChild(elink)
                    elink.click()
                    URL.revokeObjectURL(elink.href)
                    document.body.removeChild(elink)
                    this.listLoading = false
                })
            }

• 前端接口

import request from '@/utils/request'

export function dfsUpload (formData) {
    return request({
      url: '/gitegg-service-extension/extension/upload/file',
      method: 'post',
      data: formData
    })
}
export function dfsGetFileUrl (query) {
    return request({
      url: '/gitegg-service-extension/extension/get/file/url',
      method: 'get',
      params: query
    })
}

export function dfsDownloadFileUrl (query) {
  return request({
    url: '/gitegg-service-extension/extension/get/file/download',
    method: 'get',
    responseType: 'blob',
    params: query
  })
}

三、功能测试界面

1. 批量上传
   

2. 文件流下载及获取文件地址
   

备注

• 防止文件名重复，这里文件名统一采用hash算法，可以防止文件重复，在界面需要展示的文件名，则存储到数据库一个文件名字段进行展示。所有的上传文件都留有记录。

GitEgg-Cloud是一款基于SpringCloud整合搭建的企业级微服务应用开发框架，开源项目地址:

Gitee: https://gitee.com/wmz1930/GitEgg

GitHub: https://github.com/wmz1930/GitEgg