JAVA使用阿里云Serverless 函数计算将OSS文件打包成Zip批量下载

程序开发 2023-09-05 22:40:20

批量下载OSS文件的几种方法

单个文件依次下载
阿里云OSS中批量下载文件使用的就是这种单个文件依次下载的方法，下载时会弹出提示，体验不是很好，也无法下载文件夹保持文件目录结构
将OSS文件下载到自己服务器中，然后自己生成一个Zip文件，完成批量下载

这种方法的缺点下载比较慢、如果文件过多会消耗服务器CPU资源和带宽

使用阿里云函数计算打包OSS文件下载

阿里云函数计算官方Demo中有一个python的例子，可惜python用的不多，所以使用Java实现一个类似的功能

使用JAVA 打包OSS文件

创建Maven项目，添加阿里云函数计算依赖


 com.aliyun.fc.runtimefc-java-core1.4.0com.aliyun.fc.runtimefc-java-common2.2.2commons-iocommons-io2.11.0
 
 zip-ossorg.apache.maven.pluginsmaven-dependency-plugincopy-dependenciesprepare-packagecopy-dependencies${project.build.directory}/classes/libruntime

实现Http触发接口

package example;import com.aliyun.fc.runtime.Context;
 import com.aliyun.fc.runtime.Credentials;
 import com.aliyun.fc.runtime.HttpRequestHandler;
 import com.aliyun.oss.OSSClient;
 import com.aliyun.oss.model.OSSObject;
 import org.apache.commons.io.IOUtils;import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.*;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipOutputStream;public class App implements HttpRequestHandler {String endpoint = "oss-cn-hangzhou.aliyuncs.com";public void handleRequest(HttpServletRequest request, HttpServletResponse response, Context context)throws IOException {String bucket = request.getParameter("bucket");String objectKey= request.getParameter("objectKey");Credentials creds = context.getExecutionCredentials();OSSClient client = new OSSClient(endpoint, creds.getAccessKeyId(), creds.getAccessKeySecret(), creds.getSecurityToken());response.setContentType("application/x-zip-compressed");ZipOutputStream zipOutputStream = new ZipOutputStream(response.getOutputStream());String [] objectKeys=objectKey.split(",");for (String key : objectKeys) {OSSObject ossObject = client.getObject(bucket, key);ZipEntry zipEntry = new ZipEntry(key);zipOutputStream.putNextEntry(zipEntry);IOUtils.copy(ossObject.getObjectContent(), zipOutputStream);ossObject.close();}zipOutputStream.closeEntry();zipOutputStream.finish();}
 }

3.打包工程

mvn clean package