title: How to get dropped Mail message data in a Cocoa application?
body: <p>I'm working on a Cocoa application into which I'd like to allow Mail messages to be dropped.</p>
  
  <p>If I include <code>public.plain-text</code> in my Info.plist Document Types, I can drop a Mail message on the icon in the Dock and get a file path like this from the <code>application:openFiles:</code> delegate method:</p>
  
  <pre><code>"/Users/smokris/Library/Caches/TemporaryItems/Re_ multiplexer question 3.eml"
  </code></pre>
  
  <p>...and I can read the raw message data from this file.  So far so good.</p>
  
  <p>However, I also want the user to be able to drop Mail messages on the application window.  So I do this:</p>
  
  <pre><code>[window registerForDraggedTypes:[NSArray arrayWithObjects:(NSString *)kPasteboardTypeFileURLPromise,nil]];
  </code></pre>
  
  <p>...and in <code>performDragOperation:</code>, I get a URL like this from the pasteboard:</p>
  
  <pre><code>message:%3CAANLkTikeTeWYU39JpTovxF2PC0Mm=xkrU7fHNh6gGh6V@mail.gmail.com%3E
  </code></pre>
  
  <p>If I try doing an <code>NSURLRequest</code> on this URL, it gives me the error "unsupported URL".</p>
  
  <p>How can I get the raw message data from this <code>message:</code> URL?</p>