文件上传/下载操作

借助阿里云的文件存储服务【对象存储OSS】，将上传的文件存储到阿里云服服务器中。

文件上传流程

先安装依赖

        <!--阿里云对象存储服务依赖-->
        <dependency>
            <groupId>com.aliyun.oss</groupId>
            <artifactId>aliyun-sdk-oss</artifactId>
        </dependency>

FileUploadControoler

package com.powernode.controller;

import cn.hutool.core.date.DateUtil;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.model.PutObjectRequest;
import com.powernode.config.AliyunOSSConfig;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import java.net.URL;
import java.util.Date;

/**
 * 文件上传控制层
 */
@Api(tags = "文件上传接口管理")
@RequestMapping("admin/file")
@RestController
public class FileUploadController {

    @Autowired
    private AliyunOSSConfig aliyunOSSConfig;


    /**
     * 上传文件：
     * 1.接口要求请求方式必须是post请求
     * 2.接收文件的对象的类型是：MultipartFile该对象是SpringMVC提供的
     * @return
     */
    @ApiOperation("上传单个文件")
    @PostMapping("upload/element")
    public String uploadFile(MultipartFile file) {

        // 填写Bucket名称
        String bucketName = aliyunOSSConfig.getBucketName();
        // 以天为单位的名称，作为文件夹名称
        String newFolderName = DateUtil.format(new Date(), "yyyy-MM-dd");
        // 以时间戳作为文件的新名称
        String newFileName = DateUtil.format(new Date(), "HHmmssSSS");
        // 获取原文件的后缀名称
        String originalFilename = file.getOriginalFilename();
        String fileSuffix = originalFilename.substring(originalFilename.lastIndexOf("."));
        // 填写Object完整路径，完整路径中不能包含Bucket名称，例如exampledir/exampleobject.txt。
        String objectName = newFolderName+"/"+newFileName+fileSuffix;

        // 创建OSSClient实例。
        OSS ossClient = new OSSClientBuilder().build(aliyunOSSConfig.getEndpoint(), aliyunOSSConfig.getAccessKeyId(), aliyunOSSConfig.getAccessKeySecret());
        URL url = null;
        try {
            // 创建PutObjectRequest对象。
            PutObjectRequest putObjectRequest = new PutObjectRequest(bucketName, objectName, file.getInputStream());
            // 上传
            ossClient.putObject(putObjectRequest);
            // 创建上传文件访问的url地址
            url = ossClient.generatePresignedUrl(bucketName, objectName, DateUtil.offsetDay(new Date(), 365 * 10));
        } catch (Exception ce) {
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
        return url.toString();
    }
}

编写配置文件bootstrap.yml

aliyun:
  oss:
    endpoint: oss-cn-beijing.aliyuncs.com
    bucketName: abc-shop
    accessKeyId: LTAI5t9XZiy6XQRyVhszD5zy
    accessKeySecret: 9LX317PFh6wt2JlUfcjj4vd5PThPO3

写一个阿里云平台-对象存储OSS服务配置类，通过注入配置类来获取参数的值

package com.powernode.config;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.stereotype.Component;

/**
 * 阿里云平台-对象存储OSS服务配置类
 */
@Data
@AllArgsConstructor
@NoArgsConstructor
@Component
@ConfigurationProperties(prefix = "aliyun.oss")
@RefreshScope
public class AliyunOSSConfig {

    /**
     * 访问地址
     */
    private String endpoint;
    /**
     * bucket名称
     */
    private String bucketName;
    /**
     * 访问ID
     */
    private String accessKeyId;
    /**
     * 访问密钥
     */
    private String accessKeySecret;
}