实现阿里云oss云存储，简单几步

一、前言

虽然平常学习用的不多，但是用的时候再去找官方文档，也很繁琐，不如直接整理以下，方便粘贴复制，本文介绍两种图片上传方式①普通上传②服务端签名直传

1.普通上传

加载maven依赖

<dependency><groupId>com.aliyun.oss</groupId><artifactId>aliyun-sdk-oss</artifactId><version>3.15.1</version>
</dependency>

如果使用的是Java 9及以上的版本，则需要添加JAXB相关依赖

<dependency><groupId>javax.xml.bind</groupId><artifactId>jaxb-api</artifactId><version>2.3.1</version>
</dependency>
<dependency><groupId>javax.activation</groupId><artifactId>activation</artifactId><version>1.1.1</version>
</dependency>
<!-- no more than 2.3.3-->
<dependency><groupId>org.glassfish.jaxb</groupId><artifactId>jaxb-runtime</artifactId><version>2.3.3</version>
</dependency>

需要先从阿里云获取相关accessKeyId和accessKeySecret，并创建bucket，找到创建好的就可以找到相关访问路径和endpoint

附上传代码

 @Testpublic void testFindPath() throws FileNotFoundException {String endpoint = "oss-cn-beijing.aliyuncs.com";// 云账号AccessKey有所有API访问权限，建议遵循阿里云安全最佳实践，创建并使用RAM子账号进行API访问或日常运维，请登录 https://ram.console.aliyun.com 创建。String accessKeyId = "你的accessKeyId ";String accessKeySecret = "你的accessKeySecret ";String bucketName = "你的bucketName ";// 创建OSSClient实例。/*OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);*/InputStream inputStream = new FileInputStream("C:\\Users\\c2405\\Desktop\\R-C.jpg");ossClient.putObject(bucketName, "java.png", inputStream);// 关闭OSSClient。ossClient.shutdown();System.out.println("上传成功");}

2.服务端签名直传

服务端签名直传是指在服务端生成签名，将签名返回给客户端，然后客户端使用签名上传文件到OSS。由于服务端签名直传无需将访问密钥暴露在前端页面，相比客户端签名直传具有更高的安全性。本文介绍如何进行服务端签名直传。

如果使用微服务可以直接加载一个maven依赖，这样我们可以直接在当前类中注入OSS 对象使用

<!-- aliyun:对象存储oss --><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-alicloud-oss</artifactId></dependency>

import com.aliyun.oss.OSS;
import com.aliyun.oss.common.utils.BinaryUtil;
import com.aliyun.oss.model.MatchMode;
import com.aliyun.oss.model.PolicyConditions;
import com.lei.common.utils.R;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.LinkedHashMap;
import java.util.Map;/*** @author: 青山猿* @date: Created in 2023/12/26 0:20* @description:*/
@RestController
public class OssController {@AutowiredOSS ossClient;@Value("${spring.cloud.alicloud.access-key}")private String accessId;@Value("${spring.cloud.alicloud.oss.endpoint}")private String endpoint;@Value("${spring.cloud.alicloud.oss.bucket}")private String bucket;@RequestMapping("/oss/policy")public R policy(){// 填写Host名称，格式为https://bucketname.endpoint。//例如: https://guli-mall-admin.oss-cn-beijing.aliyuncs.com/123.jpgString host = "https://"+bucket+"."+endpoint;// 设置上传回调URL，即回调服务器地址，用于处理应用服务器与OSS之间的通信。OSS会在文件上传完成后，把文件上传信息通过此回调URL发送给应用服务器。//String callbackUrl = "https://192.168.0.0:8888";// 设置上传到OSS文件的前缀，可置空此项。置空后，文件将上传至Bucket的根目录下。String format = new SimpleDateFormat("yyyy-MM-dd").format(new Date());String dir = format+"/";Map<String, String> respMap = null;try {long expireTime = 30;long expireEndTime = System.currentTimeMillis() + expireTime * 1000;Date expiration = new Date(expireEndTime);// PostObject请求最大可支持的文件大小为5 GB，即CONTENT_LENGTH_RANGE为5*1024*1024*1024。PolicyConditions policyConds = new PolicyConditions();policyConds.addConditionItem(PolicyConditions.COND_CONTENT_LENGTH_RANGE, 0, 1048576000);policyConds.addConditionItem(MatchMode.StartWith, PolicyConditions.COND_KEY, dir);String postPolicy = ossClient.generatePostPolicy(expiration, policyConds);byte[] binaryData = postPolicy.getBytes("utf-8");String encodedPolicy = BinaryUtil.toBase64String(binaryData);String postSignature = ossClient.calculatePostSignature(postPolicy);respMap = new LinkedHashMap<String, String>();respMap.put("accessid", accessId);respMap.put("policy", encodedPolicy);respMap.put("signature", postSignature);respMap.put("dir", dir);respMap.put("host", host);respMap.put("expire", String.valueOf(expireEndTime / 1000));// respMap.put("expire", formatISO8601Date(expiration));} catch (Exception e) {// Assert.fail(e.getMessage());System.out.println(e.getMessage());}return R.ok().put("data",respMap);}
}

最后可以搭配element-ui上传组件使用

<el-uploadclass="upload-demo"action="objData.host":before-upload="ossPolicy":file-list="fileList":data='objData'list-type="picture"><el-button size="small" type="primary">点击上传</el-button><div slot="tip" class="el-upload__tip">只能上传jpg/png文件，且不超过500kb</div>
</el-upload>
<script>export default {data() {return {fileList: [{name: 'food.jpeg', url: 'https://fuss10.elemecdn.com/3/63/4e7f3a15429bfda99bce42a18cdd1jpeg.jpeg?imageMogr2/thumbnail/360x360/format/webp/quality/100'}, {name: 'food2.jpeg', url: 'https://fuss10.elemecdn.com/3/63/4e7f3a15429bfda99bce42a18cdd1jpeg.jpeg?imageMogr2/thumbnail/360x360/format/webp/quality/100'}],objData:{OSSAccessKeyId:'',policy:'',Signature:'',dir:'',host:'',key:''}};},methods: {ossPolicy(file){//在上传前，先进行服务器签名return new Promise((resolve,reject)=>{this.axios.get('http://loclhost:8080/oss/policy').then(res=>{//根据后台响应结果对objData赋值this.objData.OSSAccessKeyId=res.data.accsessid;this.objData.policy=res.data.policy;this.objData.Signature=res.data.signature;this.objData.dir=res.data.dir;this.objData.host=res.data.host;this.objData.key=res.data.dir+"${filename}";resolve(true); //继续上传}).catch(error=> {console.log(error);reject(false);  //停止上传})})}}}
</script>