I am trying to send an image file via HTTP Post. I can do this in Java, but I can't seem to get it working with URLExecute. I have further details on Mathematica StackExchange (bounty of 100). The only answer so far seems to suggest that this is a limitation of URLExecute and can't be done?

If it isn't possible where do you log a bug/enhancement request?

Copy of MSE post

I have to submit a form like as follows:

<input type="file" name="jpgFile">

I can't seem to find any instructions on sending this in URLExecute. If I specify the file name as the parameter it fails. If I try Import[filename, "JPG"] of the image it also fails as invalid.

I thought his might work, but I get an error "Iteration limit of 4096 exceeded". This suggests it might be working as test file is 451,107 bytes.

URLExecute[ url,
 "Method" -> "POST",
 "Headers" -> {
   "Accept" -> "application/json; charset=UTF-8"
   },
 "MultipartElements" -> { 
   {"jpgFile", "file"} -> "test.jpg"
  }
 ]

So this is another example. In this instance I am sending a text file and this appears to work.

testData = Import["test.txt","Text"];

URLExecute[
 url,
 "Method" -> "POST",
 "Headers" -> {
   "Accept" -> "application/json; charset=UTF-8"
   },
 "MultipartElements" -> { 
   {"textData", "text/plain"} -> testData
   }
 ]

From a Java point of view, the following actually works: http://stackoverflow.com/a/17174260/1167890

I would like not to be forced back into Java/MathLink if possible though.