Apache Camel server app receiving a multipart form POST (file upload) - apache-camel

Question

I'm using Camel servlet component in order to receive xml documents and now I also need to receive files (jpegs, gifs, etc). So here is how my client app is sending a file:
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.mime.MultipartEntity;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.impl.client.DefaultHttpClient;
public class HttpClientUploadHelper {
public boolean upload(final File file, final String url) {
boolean wasSent = false ;
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost(url);
MultipartEntity entity = new MultipartEntity();
entity.addPart(file.getName(), new FileBody(file));
post.setEntity(entity);
try {
HttpResponse response = client.execute(post);
wasSent = response.getStatusLine().getStatusCode()==200;
} catch (Exception e) {
}
return wasSent;
}
}
my Camel Processor then extracts the HttpServletRequest this way:
HttpServletRequest req = exchange.getIn().getHeader(Exchange.HTTP_SERVLET_REQUEST, HttpServletRequest.class);
then I have this method to finally parse and save the file:
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.FileItemIterator;
import org.apache.commons.fileupload.FileItemStream;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.io.IOUtils
... class declaration, body, etc...
void parseAndSaveFile(final HttpServletRequest req) throws Exception {
// Check that we have a file upload request
boolean isMultipart = ServletFileUpload.isMultipartContent(req);
// Create a factory for disk-based file items
FileItemFactory factory = new DiskFileItemFactory();
// Create a new file upload handler
ServletFileUpload upload = new ServletFileUpload(factory);
// Parse the request
FileItemIterator receivedFiles = upload.getItemIterator(req);
while (receivedFiles.hasNext()) {
FileItemStream file = receivedFiles.next();
if (file.isFormField()) {
System.out.println("WTF?");
} else {
String fileName = file.getName();
File uploadedFile = new File("/home/myuser/" + fileName);
FileOutputStream out = new FileOutputStream(uploadedFile);
IOUtils.copy(file.openStream(), out);
}
}
}
when I use above code within Camel, that isMultipart flag is "true" but that receivedFiles iterator doesn't contains any element. When I use above code within another project with just a plain servlet, the code works. In both ways I'm using jetty as the web container.
So is there any other way to extract the file name and it's content within my camel processor ?
Thanks!

Answer 1

Since you're using Jetty, have you considered using the included MultipartFilter instead of the FileUpload project? Super clean and easy to use.
From the javadoc:
"This class decodes the multipart/form-data stream sent by a HTML form that uses a file input item. Any files sent are stored to a temporary file and a File object added to the request as an attribute. All other values are made available via the normal getParameter API and the setCharacterEncoding mechanism is respected when converting bytes to Strings."

Answer 2

Does this help?
public void process(Exchange exchange) throws Exception {
Message in = exchange.getIn();
Set names = in.getAttachmentNames();
for(String n: names) {
System.out.println("attachment "+n);
DataHandler h = in.getAttachment(n);
if(h!=null) {
try {
Object o = h.getContent();
System.out.println(o);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
if(!names.isEmpty())
return;
}