title: On client, how do I download an image, then send as POST request to third party server?
body: <p>We're using GWT and want to download an image to the client, then send this image to another server using a POST request...</p>
  
  <p>A JavaScript/AJAX solution would be helpful too.</p>
  
  <p>Is this plausible? Can a web app access cached images from the client's browser?</p>
  
  <p>We're rookies, if this is futile please let us know. Thanks!</p>
  
  <p>UPDATE: We abandoned this approach. After doing some research it seems that the only way one can set a multipart body request is through an HTML form, even then the client has to specify what file she wants uploaded. It makes perfect sense from a security standpoint. What we were trying to do was basically route an image image from server to client to server... thanks for the help.</p>