spring boot 文件上传及路径对外可见的解决方案

╰+哭是因爲堅強的太久メ 2024-04-19 09:09 28阅读 0赞

最近项目上有一个需求，用户上传文件后，要返回外部能直接的URL，查了些资料中与搞出来了，该需求的核心点是要将上传文件的路径暴露出来，便于外部通过URL直接访问，即将虚拟路径映射问文件系统的绝对路径

现将过程整理如下：

开发环境：SpringBoot2.0以上、JDK 1.8

### 1.修改spring boot配置文件信息如下 ###

spring:
    	mvc:
            static-path-pattern: /**
        resources: #设置上传文件目录对外可见，这个参数很重要，不然上传文件对外是访问不到的
            static-locations: classpath:/META-INF/resources/,classpath:/resources/,classpath:/static/,classpath:/public/,file:${ serverInfo.uploadpath}
        servlet:
            multipart:   #配置上传文件最大size
                max-file-size: 100MB
                max-request-size: 100MB 
    
    serverInfo: #配置上传文件磁盘存储路径
        uploadpath: e:\uploadFile

### 2.上传文件代码 ###

controller

@PostMapping("upload")
        public ResultMsg uploadFile(Integer userId, MultipartFile file) { 
            long size = (long) file.getSize();
            if (size > localConfig.getMaxFileSize()) { 
                return ResultMsg.getMsg("上传文件过大，请上传小于100MB大小的文件");
            }
            ResultMsg resultMsg = fileUploadService.uploadFile(senderId,uploadType, file);
            return resultMsg;
        }

service

@Service
    public class FileUploadService { 
        @Autowired
        private LocalConfig localConfig;
        public ResultMsg uploadFile(Integer sendId, MultipartFile file){ 
            //获取操作系统文件分隔符
            String sepa = java.io.File.separator; 
            String fileName = file.getOriginalFilename();
            String fileNameSuffix = fileName.substring(fileName.lastIndexOf(".") + 1);
            String fileNamePrefix = fileName.substring(0 , fileName.lastIndexOf("."));
            String timeStr = ""+ DateUtils.getDayStr(new Date());
            //文件名为：原文件名+上传人Id+上床时间+文件后缀名
            String newFileName = fileNamePrefix + "-"+ sendId +"-"+ DateUtils.getDateStr(new Date())  + "." + fileNameSuffix;
            //从yml配置文件获取保存文件的根路径
            String baseFilePath = localConfig.getUploadFilePath();
            //保存文件的路径为：根路径/上传人ID/时间戳/
            String path = baseFilePath + sendId+ sepa + timeStr;
            //创建文件保存目录
            createDirectory(path);
            File targetFile = new File(path + sepa + newFileName);
            try { 
                //将上传文件写到服务器上指定的文件
                file.transferTo(targetFile);
                //构造上传文件的对外访问的URL
                String saveUrl =localConfig.getBaseurl()+ sendId+ "/" + timeStr + "/" + newFileName;
                FileInfo fileInfo = new FileInfo(newFileName,fileNameSuffix,saveUrl);
                return ResultMsg.getMsg(fileInfo);
            } catch (IOException e) { 
                e.printStackTrace();
                return ResultMsg.getFailedMsg(e.getMessage());
            }
        }
            public void createDirectory(String directoryPath){ 
            File targetFile = new File(directoryPath);
            if (!targetFile.exists()) { 
                targetFile.mkdirs();
            }
        }
    }

FileInfo.java 返回给前端的数据结构，包括文件名、URL、文件后缀名等信息

@Data  
    public class FileInfo { 
        public FileInfo(){ }
        public FileInfo(String fileName,String fileType,String fileUrl){ 
            this.fileName = fileName;
            this.fileType= fileType;
            this.fileUrl = fileUrl;
        }
        public String fileName;
        public String fileType;
        public String fileUrl;
    }

LocalConfig.java是配置信息的加载类

@Component
    @Data
    public class LocalConfig { 
         public LocalConfig() { }
        private Logger logger = LoggerFactory.getLogger(getClass().getName());
        @Value("${serverInfo.uploadpath}")
        private String uploadFilePath;
        @Value("${spring.servlet.multipart.max-file-size}")
        private String maxfilesize;
        @Value("${serverInfo.baseurl}")
        private String baseurl;
        
        public Long getMaxFileSize(){ 
            String str = maxfilesize.substring(0,maxfilesize.length()-2);
            Long maxSize = 1024 * 1024 * Long.parseLong(str);
            return maxSize;
        }
    }