【文件上传】阿里云对象存储服务实现文件上传

一、基础

上传到本地：

package org.example.controller;

import lombok.extern.slf4j.Slf4j;
import org.example.pojo.Result;
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.io.File;
import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/upload")
@Slf4j
public class FileUploadController {

    @PostMapping
    public Result<String> upload(MultipartFile file) throws IOException {
        //把文件的内容存储到本地磁盘
        String originalFilename = file.getOriginalFilename();
        //保证文件名字唯一，防止覆盖UUID
       String fileName =  UUID.randomUUID().toString() + originalFilename.substring(originalFilename.lastIndexOf("."));
        file.transferTo(new File("C:\\Users\\Arata\\Desktop\\file\\" + fileName));
        return Result.success("url访问地址...");
    }
}

上传图片大小超过最大限制，修改yml文件：

spring：
    servlet:
        multipart:
           max-file-size: 50MB
           max-request-size: 50MB
    server:
        tomcat:
        max-swallow-size: 10MB

阿里云对象存储OSS (Object Storage Service)，是一款海量、安全、低成本、高可靠的云存储服务。使用OSS，您可以通过网络随时存储和调用包括文本、图片、音频和视频等在内的各种文件。
第三方服务的通用思路：

二、创建bucket

此时需要开启允许读权限，所以需要关闭阻止公共访问，无法修改！那么先完成创建，后进入bucket去进行修改：

修改完成后如下：

此时再修改读写权限（点击设置，并将权限修改为公共读）：

三、获取AccessKey

点击头像，找到AccessKey管理


点击创建AccessKey之后，验证身份，后生成AccessKeyId和AccessKeySecret（只生成一次，注意保存好）

四、参考官方SDK编写入门程序

https://help.aliyun.com/zh/oss/developer-reference/getting-started?spm=a2c4g.11186623.help-menu-31815.d_5_2_1_0.1d8d64femaflJE#0cf90ff8b28eg
由文档可以获得：
①导入阿里云坐标：

<dependency>
    <groupId>com.aliyun.oss</groupId>
    <artifactId>aliyun-sdk-oss</artifactId>
    <version>3.17.4</version>
</dependency>

②上传文件：对象/文件——>上传文件——>简单上传

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.PutObjectRequest;
import com.aliyun.oss.model.PutObjectResult;
import java.io.File;

public class Demo {

    public static void main(String[] args) throws Exception {
        // Endpoint以华东1（杭州）为例，其它Region请按实际情况填写。
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // 从环境变量中获取访问凭证。运行本代码示例之前，请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // 填写Bucket名称，例如examplebucket。
        String bucketName = "examplebucket";
        // 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 = "exampledir/exampleobject.txt";
        // 填写本地文件的完整路径，例如D:\\localpath\\examplefile.txt。
        // 如果未指定本地路径，则默认从示例程序所属项目对应本地路径中上传文件。
        String filePath= "D:\\localpath\\examplefile.txt";
        // 填写Bucket所在地域。以华东1（杭州）为例，Region填写为cn-hangzhou。
        String region = "cn-hangzhou";
        
        // 创建OSSClient实例。
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {
            // 创建PutObjectRequest对象。
            PutObjectRequest putObjectRequest = new PutObjectRequest(bucketName, objectName, new File(filePath));
            // 如果需要上传时设置存储类型和访问权限，请参考以下示例代码。
            // ObjectMetadata metadata = new ObjectMetadata();
            // metadata.setHeader(OSSHeaders.OSS_STORAGE_CLASS, StorageClass.Standard.toString());
            // metadata.setObjectAcl(CannedAccessControlList.Private);
            // putObjectRequest.setMetadata(metadata);
            
            // 上传文件。
            PutObjectResult result = ossClient.putObject(putObjectRequest);           
        } 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();
            }
        }
    }
}  

五、集成改造

改造成工具类 AliOssUtil.class

package com.itheima.bigeventadmin.utils;

import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;

import java.io.InputStream;

public class AliOssUtil {
    private static final String ENDPOINT = "https://oss-cn-beijing.aliyuncs.com";
    private static final String ACCESS_KEY_ID = "LTAI5tQ8e13igWZUMTjMEEQV";
    private static final String SECRET_ACCESS_KEY = "MffMJoM24sc59SEBEJQDb0cfBVOAC9";
    private static final String BUCKET_NAME = "big-event-gwd";

    //上传文件,返回文件的公网访问地址
    public static String uploadFile(String objectName, InputStream inputStream){
        // 创建OSSClient实例。
        OSS ossClient = new OSSClientBuilder().build(ENDPOINT,ACCESS_KEY_ID,SECRET_ACCESS_KEY);
        //公文访问地址
        String url = "";
        try {
            // 创建存储空间。
            ossClient.createBucket(BUCKET_NAME);
            ossClient.putObject(BUCKET_NAME, objectName, inputStream);
            url = "https://"+BUCKET_NAME+"."+ENDPOINT.substring(ENDPOINT.lastIndexOf("/")+1)+"/"+objectName;
        } 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();
            }
        }
        return url;
    }
}

六、调用工具类

    @PostMapping
    public Result<String> upload(MultipartFile file) throws Exception {
        //把文件的内容存储到本地磁盘
        String originalFilename = file.getOriginalFilename();
        //保证文件名字唯一，防止覆盖UUID
       String fileName =  UUID.randomUUID().toString() + originalFilename.substring(originalFilename.lastIndexOf("."));
        //file.transferTo(new File("C:\\Users\\Arata\\Desktop\\file\\" + fileName));
        String url = AliOssUtil.uploadFile(fileName, file.getInputStream());
        return Result.success(url);
    }

测试结果：