阿里云OSS文件上传

文件上传指的是本地上传图片、视频、音频等上传文件到服务器上，可以提供其他用户浏览或是下载过程。为文件上传在项目中应用非常广泛，我们经常发的抖音、朋友圈都用到了文件上传功能。

实现文件上传服务，需要有存储的支持，那我们的解决方案将以下几种：

1.直接将图片保存到服务的硬盘的（springmvc中的文件上传）

        1.优点：开发便捷，成功低

        2.缺点：扩容困难

2.使用分布式文件系统进行存贮

        1.优点：容易实现扩容

        2.缺点：开发复杂度稍大（有成熟的产品可以使用，比如：FastDFS，MinIO）

3.使用第三方的存储服务（例如OSS）

        1.优点：开发简单，拥有强大功能，免维护

        2.缺点：付费

实现步骤：

1）定义OSS相关配置

applicate-dev.yml

 alioss:
    endpoint: oss-cn-hangzhou.aliyuncs.com
    access-key-id: 你的服务器id
    access-key-secret: 服务器私密
    bucket-name: 项目名

---

2). 读取OSS配置

@Component
@ConfigurationProperties(prefix = "alioss")
@Data
public class AliOssProperties {

    private String endpoint;
    private String accessKeyId;
    private String accessKeySecret;
    private String bucketName;

}

3). 生成OSS工具类对象

@Configuration
@Slf4j
public class OssConfiguration {

    @Bean
    @ConditionalOnMissingBean
    public AliOssUtil aliOssUtil(AliOssProperties aliOssProperties){
        log.info("开始创建阿里云文件上传工具类对象：{}",aliOssProperties);
        return new AliOssUtil(aliOssProperties.getEndpoint(),
                aliOssProperties.getAccessKeyId(),
                aliOssProperties.getAccessKeySecret(),
                aliOssProperties.getBucketName());
    }
}

AliOssUtil.java

@Data
@AllArgsConstructor
@Slf4j
public class AliOssUtil {

    private String endpoint;
    private String accessKeyId;
    private String accessKeySecret;
    private String bucketName;

    /**
     * 文件上传
     *
     * @param bytes
     * @param objectName
     * @return
     */
    public String upload(byte[] bytes, String objectName) {

        // 创建OSSClient实例。
        OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);

        try {
            // 创建PutObject请求。
            ossClient.putObject(bucketName, objectName, new ByteArrayInputStream(bytes));
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }

        //文件访问路径规则 https://BucketName.Endpoint/ObjectName
        StringBuilder stringBuilder = new StringBuilder("https://");
        stringBuilder
                .append(bucketName)
                .append(".")
                .append(endpoint)
                .append("/")
                .append(objectName);

        log.info("文件上传到:{}", stringBuilder.toString());

        return stringBuilder.toString();
    }
}

4). 定义文件上传接口

/**
 * 通用接口
 */
@RestController
@RequestMapping("/admin/common")
@Api(tags = "通用接口")
@Slf4j
public class CommonController {

    @Autowired
    private AliOssUtil aliOssUtil;

    /**
     * 文件上传
     * @param file
     * @return
     */
    @PostMapping("/upload")
    @ApiOperation("文件上传")
    public Result<String> upload(MultipartFile file){
        log.info("文件上传：{}",file);

        try {
            //原始文件名
            String originalFilename = file.getOriginalFilename();
            //截取原始文件名的后缀   dfdfdf.png
            String extension = originalFilename.substring(originalFilename.lastIndexOf("."));
            //构造新文件名称
            String objectName = UUID.randomUUID().toString() + extension;

            //文件的请求路径
            String filePath = aliOssUtil.upload(file.getBytes(), objectName);
            return Result.success(filePath);
        } catch (IOException e) {
            log.error("文件上传失败：{}", e);
        }

        return Result.error(MessageConstant.UPLOAD_FAILED);
    }
}