Apache FileUpload 不适用于 springboot：ServletFileUpload.parseRequest 始终为空

Posted 2023-02-19

【中文标题】Apache FileUpload 不适用于 springboot：ServletFileUpload.parseRequest 始终为空

【英文标题】：Apache FileUpload doesn't work with springboot : ServletFileUpload.parseRequest is always empty

【发布时间】：2022-01-21 21:50:08

【问题描述】：

我正在使用 springboot 2.2.6.RELEASE 和 commons-fileupload 1.4 我已经禁用 spring.servlet.multipart 如下：

spring.servlet.multipart.enabled = false

我的控制器如下：

@RequestMapping(value = "/UploadFileServlet", method = RequestMethod.POST)
public void doPost(HttpServletRequest request, HttpServletResponse response) throws Exception 
    try 
        boolean isMultipart = ServletFileUpload.isMultipartContent(request);

        if (isMultipart) 
            DiskFileItemFactory factory = new DiskFileItemFactory();
            factory.setRepository(new File(System.getProperty("java.io.tmpdir")));
            factory.setSizeThreshold(DiskFileItemFactory.DEFAULT_SIZE_THRESHOLD);
            factory.setFileCleaningTracker(null);
            ServletFileUpload upload = new ServletFileUpload(factory);
            List<FileItem> items = upload.parseRequest(request);

            String imageFileName = request.getParameter("imageFileName");

            Iterator<FileItem> iter = items.iterator();
            while (iter.hasNext()) 
                FileItem item = (FileItem) iter.next();
                if (!item.isFormField()) 
                    try (InputStream uploadedStream = item.getInputStream();
                         OutputStream out = new FileOutputStream(imageFileName);) 
                        IOUtils.copy(uploadedStream, out);
                    
                
            
        
     catch (Exception e) 
        throw new RuntimeException(e);
    

问题：upload.parseRequest 总是返回一个空列表

【问题讨论】：

HttpServletRequest 是否未包装且 ServletInputStream 已被读取？

我不明白

HttpServletRequest.getInputStream() 如果不是包装器，则只能读取一次。见this question

我知道，而且我没有在其他任何地方读过它，我怀疑可能有一个过滤器或拦截器不是那个

Spring Boot 在其过滤器链中读取了一次 inputStream

【参考方案1】：

我找到了解决方案，我有一个针对 primefaces 库的文件上传过滤器，它没有为特定的 url 模式配置，所以它正在窃取请求，在我为其配置 url 模式后，问题就解决了：

@Bean
    public FilterRegistrationBean FileUploadFilter() 
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setFilter(new org.primefaces.webapp.filter.FileUploadFilter());
        registration.setName("PrimeFaces FileUpload Filter");
        registration.addUrlPatterns("/faces/*");
        registration.addUrlPatterns("*.xhtml");
        return registration;