IDEA阿里云OSS实现文件上传·解决苍穹外卖图片回显

简单交代配置阿里云OSS的思路

1. 首先去阿里云开通一个OSS服务，配置好一个自己的Bucket

2. 在IDEA配置Bucket

3. 拷贝官网的OSS工具类代码

package com.sky.utils;import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.extern.slf4j.Slf4j;
import java.io.ByteArrayInputStream;@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/ObjectNameStringBuilder 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. OSS工具类对象的创建

package com.sky.config;import com.sky.properties.AliOssProperties;
import com.sky.utils.AliOssUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;/*** 配置类，用于创建AliOssUtil对象*/
@Configuration
@Slf4j
public class OssConfiguration {// 通过参数注入的方式，将Oss的配置信息传递进来// Bean 如果容器中没有AliOssUtil对象，则创建AliOssUtil对象// ConditionalOnBean 表示如果容器中存在AliOssUtil对象，则不创建AliOssUtil对象@Bean@ConditionalOnMissingBeanpublic AliOssUtil aliOssUtil(AliOssProperties aliOssProperties) {log.info("开始创建阿里云文件上传工具类对象:{}",aliOssProperties);// 创建AliOssUtil对象，并传入配置信息return new AliOssUtil(aliOssProperties.getEndpoint(),aliOssProperties.getAccessKeyId(),aliOssProperties.getAccessKeySecret(),aliOssProperties.getBucketName());}
}

5. 在Controller层编写文件上传逻辑

// Autowired注解的作用:自动将匹配的Bean装配到@Autowired标注的变量、方法或构造函数上。(依赖注入)@Autowiredprivate AliOssUtil aliOssUtil;/*** 文件上传* @param file* @return*/@PostMapping("/upload")@ApiOperation("文件上传")public Result<String> upload(MultipartFile file) {log.info("文件上传接口被调用:{}",file);String filePath = null;try {//  获取原始文件名String originalFilename = file.getOriginalFilename();// 截取原始文件名的扩展名String extName = originalFilename.substring(originalFilename.lastIndexOf("."));// 生成新的文件名: UUID + 扩展名String newFileName = UUID.randomUUID().toString() + extName;// 文件上传请求路径filePath = aliOssUtil.upload(file.getBytes(), newFileName);}catch(IOException e){e.printStackTrace();log.error("文件上传失败:{}",e);return Result.error(MessageConstant.UPLOAD_FAILED);}return Result.success(filePath);}

6. 测试（省略，做到这里基本无误了）

接下来就来讲讲文件回显失败的几点调试方向

文件回显失败的原因及其排查方向

1. 检查你文件上传拼接的url是否正确

这一步如果错了，实际上上传就已经错了，更别提回显这方面的事情了

2. 首先，如果你全程跟着苍穹老师写的代码去做，必然会导致文件回显失败，我记得视频里面的代码最后是没有返回文件上传路径的，你可以改一下再尝试

具体的，苍穹老师写的文件上传代码：

问题就出在成功的时候还封装了错误的信息进行返回，你应该要把错误的返回放到catch中，成功后把文件路径放到Result中

/*** 文件上传* @param file* @return*/@PostMapping("/upload")@ApiOperation("文件上传")public Result<String> upload(MultipartFile file) {log.info("文件上传接口被调用:{}",file);try {//  获取原始文件名String originalFilename = file.getOriginalFilename();// 截取原始文件名的扩展名String extName = originalFilename.substring(originalFilename.lastIndexOf("."));// 生成新的文件名: UUID + 扩展名String newFileName = UUID.randomUUID().toString() + extName;// 文件上传请求路径String filePath  = aliOssUtil.upload(file.getBytes(), newFileName);}catch(IOException e){e.printStackTrace();log.error("文件上传失败:{}",e);}return Result.error(MessageConstant.UPLOAD_FAILED);}