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POFile Image to Servlet Fails
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copied!<p>I am trying to upload an image to a servlet, but every once and a while during automated testing, it silently fails.</p> <p>Do you guys know what would cause this?</p> <p>Here is the code on the server:</p> <pre><code> @ResponseBody @RequestMapping(method = RequestMethod.POST) public String upload(HttpServletRequest request) throws Exception { BufferedImage image = null; @SuppressWarnings("unchecked") List<FileItem> items = new ServletFileUpload( new DiskFileItemFactory()).parseRequest(request); Logger.log(LogLevel.INFO, "Upload contains " + items.size() + " items."); int i = 0; for (FileItem item : items) { Logger.log(LogLevel.INFO, "\tItem " + (i++) + ". Name:\t" + item.getName() + ", Type:\t" + item.getContentType()); // File is of type "file" if (!item.isFormField()) { InputStream inputStream = null; try { inputStream = item.getInputStream(); if (inputStream.available() == 0) { Logger.log(LogLevel.WARN, "Item shows file type, but no bytes are available"); } image = ImageIO.read(inputStream); if (image != null) { break; } } catch (Exception e) { Logger.log(LogLevel.ERROR, "There was an error reading the image. " + ExceptionUtils.getFullStackTrace(e)); throw new Exception("image provided is not a valid image"); } finally { if (inputStream != null) { IOUtils.closeQuietly(inputStream); } } } } if (image == null) { Logger.log(LogLevel.ERROR, "Image was supposedly read correctly, but was null afterwards"); throw new Exception("Image provided could not be read"); } //do stuff with image ... } </code></pre> <p>Here is the test:</p> <pre><code> public void testImageUpload throws Exception { HttpPost httppost = new HttpPost("path/to/endpoint"); File file=new File(imgLoc); FileBody bin = new FileBody(file); StringBody comment = new StringBody("Filename: " + file); MultipartEntity reqEntity = new MultipartEntity(); reqEntity.addPart("upload-file", bin); reqEntity.addPart("comment", comment); httppost.setHeader("Accept", "application/json"); httppost.setHeader("Connection","Keep-Alive"); httppost.setEntity(reqEntity); HttpResponse response =testClient.getClient().execute(httppost); imgResponse=response.getStatusLine().toString(); System.out.println(imgResponse); BufferedReader reader = new BufferedReader( new InputStreamReader(response.getEntity().getContent())); String line; while ((line = reader.readLine()) != null){ output = output + " " +line;} System.out.println("Image Response: "+output); } </code></pre> <p>Here is the output from the server when it fails:</p> <pre><code>2013/10/02 05-53-32,287::LOG:INFO[com.example#upload:L130 -- Upload contains 2 items.] 2013/10/02 05-53-32,288::LOG:INFO[com.example#upload:L133 -- Item 0. Name: Dog.jpg, Type: application/octet-stream] 2013/10/02 05-53-32,288::LOG:WARN[com.example#upload:L140 -- Item shows file type, but no bytes are available] 2013/10/02 05-53-32,289::LOG:INFO[com.example#upload:L133 -- Item 1. Name: null, Type: text/plain; charset=ISO-8859-1] 2013/10/02 05-53-32,290::LOG:ERROR[com.example#upload:L159 -- Image was supposedly read correctly, but was null afterwards] </code></pre> <p>We catch the exception from the image upload and send back a response code of 422 back to the client, so on the test, we get <code>imgResponse</code>==422 which is a failure case.</p> <p><strong>Note: this only happens <em>sometimes</em> you run the test.</strong></p>

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