How to implement the file upload and download function? The following article will introduce to you how to implement file upload and download functions based on gitee. I hope it will be helpful to you!
Selection of solutions
File uploading and downloading are the core functions of our project, and they also integrate and optimize previous boot project to implement this function.
For uploading and downloading files, Alibaba Cloud OSS and Huawei Cloud OSS are generally used. They are very easy to use and officially provide a graphical interface. However, these methods require storage fees based on volume and are similar to gitee. Call the official interface to implement the function. Because I am in the learning stage, I chose to build a warehouse in gitee, use the official API to initiate file upload and delete functions to the warehouse, and use the file address stored in the database to download the file to the browser server client.
Design of database tables
The database table only uses two tables to implement basic functions, one is a file table and the other is a folder table
public class File {
@TableId(type = IdType.AUTO)
private Long id;
private String fileName;
private String filePath;
private String fileSize;
@TableField(fill = FieldFill.INSERT)
@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss", timezone = "GMT+8")
private Date createTime;
private Long userId;
private Long folderId;
//分享次数
private Integer shareTimes;
//文件描述
private String fileCover;
}Copy after login
public class Folder {
@TableId(type = IdType.AUTO)
private Long id;
private String folderName;
private Long fatherId; //父文件夹id,为0表示没有最上层文件夹
private Long userId;
private String folderCover;
private Boolean folderPermissions;
@TableField(fill = FieldFill.INSERT)
@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss", timezone = "GMT+8")
private Date createTime;
}Copy after login
Build a gitee warehouse
First open your own gitee and create a new warehouse, fill in the name, check the initialization warehouse, and set it as open source after creation
After the warehouse is created, open "Personal Home Page" -> "Personal Settings" -> "Private Token" to generate a new private token for yourself for authentication when calling the official interface. .
# Don’t worry about the options when generating. Be careful to save your own token, because it will only be displayed once.
Compilation of gitee image bed tool class
Just copy the one written by others and pay attention to the private token, personal space, warehouse name, and default inside The storage address needs to be changed to your own. This tool class uses this information to initiate an upload request to the gitee repository through the HttpUtil tool class.
package com.ityz.file.util;
import cn.hutool.core.codec.Base64;
import cn.hutool.http.HttpUtil;
import cn.hutool.http.Method;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;
/**
* @ClassName UploadGiteeImgBedUtil
* @Author ityz
* @Date 2022/11/23 16:38
* @Description Gitee图床工具类
*/
public class GiteeImgBedUtil {
/**
* 码云私人令牌
*/
private static final String ACCESS_TOKEN = "0616f0e894e3c264bac45591e34a43bc"; //这里不展示我自己的了，需要你自己补充
/**
* 码云个人空间名
*/
private static final String OWNER = "procedure-yuan-yanzu";
/**
* 上传指定仓库
*/
private static final String REPO = "files";
/**
* 默认上传时指定存放图片路径
*/
public static final String PATH = "files/";
//API
/**
* 新建(POST)、获取(GET)、删除(DELETE)文件：()中指的是使用对应的请求方式
* %s =>仓库所属空间地址(企业、组织或个人的地址path) (owner)
* %s => 仓库路径(repo)
* %s => 文件的路径(path)
*/
private static final String API_CREATE_POST = "https://gitee.com/api/v5/repos/%s/%s/contents/%s";
/**
* 生成创建(获取、删除)的指定文件路径
* @param originalFilename 原文件名
* @param path 存储文件路径
* @return
*/
private static String createUploadFileUrl(String originalFilename,String path){
String targetPath = path == null ? GiteeImgBedUtil.PATH : path;
//获取文件后缀
String suffix = FileUtil.getFileSuffix(originalFilename);
//拼接存储的图片名称
String fileName = System.currentTimeMillis()+"_"+ UUID.randomUUID().toString()+suffix;
//填充请求路径
String url = String.format(GiteeImgBedUtil.API_CREATE_POST,
GiteeImgBedUtil.OWNER,
GiteeImgBedUtil.REPO,
targetPath + fileName);
return url;
}
private static String createDelFileUrl(String path){
//填充请求路径
String url = String.format(GiteeImgBedUtil.API_CREATE_POST,
GiteeImgBedUtil.OWNER,
GiteeImgBedUtil.REPO,
path);
return url;
}
private static String createGetUrl(String path){
String targetPath = path == null ? GiteeImgBedUtil.PATH : path;
//填充请求路径
String url = String.format(GiteeImgBedUtil.API_CREATE_POST,
GiteeImgBedUtil.OWNER,
GiteeImgBedUtil.REPO,
targetPath);
return url;
}
/**
* 获取创建文件的请求体map集合：access_token、message、content
* @param multipartFile 文件字节数组
* @return 封装成map的请求体集合
*/
private static Map<string> getUploadBodyMap(byte[] multipartFile){
HashMap<string> bodyMap = new HashMap(3);
bodyMap.put("access_token", GiteeImgBedUtil.ACCESS_TOKEN);
bodyMap.put("message", "add file!");
bodyMap.put("content", Base64.encode(multipartFile));
return bodyMap;
}
/**
* 创建普通携带请求体集合内容
* @param map 额外参数
* @param message 请求信息
* @return
*/
private static Map<string> getCommonBodyMap(HashMap map, String message){
HashMap<string> bodyMap = new HashMap(2);
bodyMap.put("access_token", GiteeImgBedUtil.ACCESS_TOKEN);
bodyMap.put("message", message);
if (map != null){
bodyMap.putAll(map);
}
return bodyMap;
}
/**
* **********封装好的实际调用方法*******************
*/
//超时
private static int TIMEOUT = 10 * 1000;
/**
* 上传文件
* @param filename 文件名称
* @param path 路径
* @param sha 必备参数from 获取仓库具体路径下的内容
* @return
*/
public static String uploadFile(String path, String originalFilename, byte[] data){
String targetURL = GiteeImgBedUtil.createUploadFileUrl(originalFilename,path);
//请求体封装
Map<string> uploadBodyMap = GiteeImgBedUtil.getUploadBodyMap(data);
return HttpUtil.post(targetURL, uploadBodyMap);
}
/**
* 删除指定path路径下的文件
* @param filename 文件名称
* @param path 路径
* @param sha 必备参数from 获取仓库具体路径下的内容
* @return
*/
public static String deleteFile(String path,String sha){
String delFileUrl = createDelFileUrl(path);
HashMap<string> needMap = new HashMap(1);
needMap.put("sha",sha);//添加sha参数
return HttpUtil.createRequest(Method.DELETE, delFileUrl)
.form(getCommonBodyMap(needMap,"del file!")) //构建请求表单
.timeout(TIMEOUT)
.execute().body();
}
/**
* 获取仓库具体路径下的内容，主要是获取 sha
* @param path
* @return
*/
public static String getSha(String path){
String getShaUrl = createDelFileUrl(path);
return HttpUtil.createRequest(Method.GET, getShaUrl)
.form(getCommonBodyMap(null, "get sha!"))
.timeout(TIMEOUT)
.execute().body();
}
}</string></string></string></string></string></string>Copy after login
File upload interface
The process of file upload is to pass in the file object and related information to the front end, and then we initiate a request to gitee to transfer the file to the warehouse. After the upload is successful, The returned download address and related information are stored in the database.
Intermediate tool class
Here we first write an intermediate tool class to initiate requests and get results. If this code is also written in the service, the code will appear too large. It’s too complicated, so I wrote it separately.
import cn.hutool.json.JSONObject;
import cn.hutool.json.JSONUtil;
import com.ityz.common.constants.GiteeConstant;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.multipart.MultipartFile;
import java.io.IOException;
/**
* gitee文件操作api
*/
@Slf4j
public class GiteeApi {
/**
* 上传文件api
* @param multipartFile 前端传入的文件对象
* @param folder 文件所存文件夹名称
* @return gitee的api上传返回值的json对象
* @throws IOException
*/
public static JSONObject upload(MultipartFile multipartFile,String folder) throws IOException {
log.info("uploadFile()请求已来临...");
//根据文件名生成指定的请求url
String originalFilename = multipartFile.getOriginalFilename();
if (originalFilename == null) {
log.info("服务器接收文件失败！");
}
//Gitee请求：发送上传文件请求
String JSONResult = GiteeImgBedUtil.uploadFile(folder, originalFilename, multipartFile.getBytes());
//解析响应JSON字符串
//上传txt文件时会出问题，没解决
JSONObject jsonObj = JSONUtil.parseObj(JSONResult);
//请求失败
if (jsonObj.getObj(GiteeConstant.RESULT_BODY_COMMIT) == null) {
log.info("上传文件失败！");
}
//请求成功：返回下载地址
JSONObject content = JSONUtil.parseObj(jsonObj.getObj(GiteeConstant.RESULT_BODY_CONTENT));
log.info("上传成功，下载地址为：" + content.getStr(GiteeConstant.RESULT_BODY_DOWNLOAD_URL));
return content;
}
}Copy after login
Controller
After the controller gets the file and information, it calls the intermediate tool class to upload the file, then gets the user id from the request header and the return object. Just store the file information in the File class and then use mybatisplus to store the object in the database.
@RestController
@Slf4j
@RequestMapping("/file")
public class FileController {
@Autowired
private FileService fileService;
@Autowired
private HttpServletRequest request;
/**
* 文件上传接口
* @param multipartFile 上传的文件对象
* @param fileCover 文件的描述信息
* @param folderId 文件所属的文件夹id
* @return 用户文件地址
* @throws IOException
*/
@PostMapping("/upload")
public Result<string> uploadFile(@RequestParam("file") MultipartFile multipartFile
, @RequestParam("fileCover") String fileCover
, @RequestParam("folderId") Long folderId) throws IOException {
JSONObject content = GiteeApi.upload(multipartFile, "test/");
//获取userId
Long userId = Long.valueOf(TokenUtil.parseToken(request.getHeader("token")));
File file = new File();
file.setFileCover(fileCover);
file.setUserId(userId);
file.setFolderId(folderId);
file.setFileName(content.getStr(GiteeConstant.RESULT_BODY_NAME));;
file.setFileSize(content.getStr(GiteeConstant.RESULT_BODY_SIZE));
file.setFilePath(content.getStr(GiteeConstant.RESULT_BODY_DOWNLOAD_URL));
fileService.fileUpload(file);
return new Result(ResultCode.SUCCESS,ResultCode.UP_FILE_SUCCESS,content.getStr(GiteeConstant.RESULT_BODY_DOWNLOAD_URL));
}
}</string>Copy after login
The service is relatively simple, just set a storage time and call mapper to save it
/**
* 上传文件
*
* @param file 用于向数据库储存的文件对象
*/
@Override
public void fileUpload(File file) {
file.setCreateTime(new Date());
fileMapper.insert(file);
}Copy after login
Interface test
We can upload a file at will
Check if gitee and database have corresponding results
The id here is 2 because before If a piece of data is deleted, you can just truncate the table from the beginning.
File download interface
File download bothered me initially. There are two ways. The first is to directly write the file object to the local folder provided by the user. address, the second is to download the file to the browser. Finally, the second method was chosen, because the user does not need to set the download address and can see the download process when downloading in the browser. The whole process is to use the download address to convert the file into a file stream and write it into a byte array, and then use the browser to download through method writes a byte array to the output stream.
controller
Use the file ID to first find the corresponding address from the database and then use the address to complete subsequent operations.
/**
* 文件下载接口
* @param fileId 文件id
* @param response http响应对象
* @return 下载结果
*/
@GetMapping("/download")
public Result<string> download(Long fileId,HttpServletResponse response) {
try {
String downloadUrl = fileService.downloadFile(fileId);
URL url = new URL(downloadUrl);
URLConnection conn = url.openConnection();
InputStream bis = conn.getInputStream();
byte[] bytes = new byte[bis.available()];
OutputStream os = response.getOutputStream();
// 从文件流读取字节到字节数组中
while (bis.read(bytes) != -1) {
// 重置 response
response.reset();
// 设置 response 的下载响应头
response.setContentType("application/x-download");
response.setHeader("Content-disposition", "attachment;filename=" + URLEncoder.encode(FileUtil.getFileName(downloadUrl), "UTF-8")); // 注意，这里要设置文件名的编码，否则中文的文件名下载后不显示
// 写出字节数组到输出流
os.write(bytes);
// 刷新输出流
os.flush();
}
return new Result(ResultCode.SUCCESS,ResultCode.DOWN_FILE_SUCCESS);
}catch (Exception e){
e.printStackTrace();
return new Result(ResultCode.FAIL,ResultCode.DOWN_FILE_FAIL);
}
}</string>Copy after login
Here you need to write a tool class to get the file name, otherwise the browser will not know the file type after downloading
/**
* 获取url中的文件名（取到最后一个/后面的就是文件名）
* @param url 文件地址
* @return
*/
public static String getFileName(String url) {
if(!url.equals("")){
return url.substring(url.lastIndexOf("/")+1);
}
else return "文件地址错误";
}Copy after login
接口测试
发送请求完成下载
文件删除接口
中间工具类
/**
* 删除文件api
* @param url 文件地址
*/
public static void del(String url){
if (!url.equals("") && !url.contains("master/")) {
log.info("url：" + url + " 无法解析路径！");
}
String path = url.substring(url.indexOf("master/") + 7);
log.info("解析取得待删除路径：" + path);
String shaResult = GiteeImgBedUtil.getSha(path);
JSONObject jsonObj = JSONUtil.parseObj(shaResult);
String sha = jsonObj.getStr(GiteeConstant.RESULT_BODY_SHA);
//3、Gitee请求：发送删除请求
String JSONResult = GiteeImgBedUtil.deleteFile(path, sha);
jsonObj = JSONUtil.parseObj(JSONResult);
if (jsonObj.getObj(GiteeConstant.RESULT_BODY_COMMIT) == null) {
log.info("删除文件失败！");
}
log.info("文件路径为：" + path + " 删除成功！");
}Copy after login
service
获取文件地址并删除数据库数据
/**
* 删除文件
* @param fileId 文件id
* @return
*/
@Override
public String delFile(Long fileId) {
String url = fileMapper.selectById(fileId).getFilePath();
fileMapper.deleteById(fileId);
return url;
}Copy after login
controller
**
* 删除文件接口
* @param fileId 前端传入的文件id
* @return
*/
@GetMapping("/del")
public Result<string> delFile(Long fileId) {
try {
String url = fileService.delFile(fileId);
GiteeApi.del(url);
return new Result(ResultCode.SUCCESS,ResultCode.DEL_FILE_SUCCESS);
}
catch (Exception e){
e.printStackTrace();
return new Result(ResultCode.FAIL,ResultCode.DEL_FILE_FAIL);
}
}</string>Copy after login
接口测试
发送请求删除文件
查看数据库和gitee仓库
自此完成了文件的上传和下载功能，大家有需要的可以参考。
（学习视频分享：编程基础视频）
The above is the detailed content of How to implement the function of uploading and downloading files based on gitee. For more information, please follow other related articles on the PHP Chinese website!
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
