Re: Drag images from Firefox to org-mode

[Rick Frankel <rick@rickster.com>]

On 2013-10-17 10:48, Nicolas Richard wrote:
> Rick Frankel <rick@rickster.com> writes:
> On 2013-10-17 08:43, Nicolas Richard wrote:
> Carsten Dominik <drostekirsten@gmail.com> writes:
> does anyone know how general this code is?  Does it works on
> different operating systems?
> We might want to include this into the Org core.
> 
> Since it is based on dnd, and since the documentation of dnd reads:
> ;; This file provides the generic handling of the drop part only.
> ;; Different DND backends (X11, W32, etc.) that handle the platform
> ;; specific DND parts call the functions here to do final delivery of
> ;; a drop.
> I'd highly suspect that the code is portable.
> 
> It does make use of `wget', which may not be avalalable on all systems
> (e.g., i believe os x only includes `curl' by default.) So it would
> need to allow configuration of the image fetch command.
> 
> 
> I'm sorry I missed that. Indeed, on the one "OS X" I ever tried to run
> wget on, it didn't have wget.
> 
> Perhaps url-retrieve can be used instead. I have no time right now to
> code it right, but here's a (synchronous) example with url + filetype +
> filename all hardcoded :
> 
> (with-current-buffer
> (url-retrieve-synchronously
> "http://www.cnrtl.fr/images/css/bandeau.jpg")
> (delete-region
> (point-min)
> (progn
> (re-search-forward "^$" nil 'move)
> (point)))
> (write-file
> (expand-file-name "~/tmp/foobar.jpg"))
> (pop-to-buffer
> (current-buffer)))
> 
> using url-retrieve (which is asynchroneous)  might also lift the
> requirement on async.el

One small problem, should be =(1+ (point))=, as the above leaves a
blank newline at the head of the jpg, making it invalid.

Here's an async implementation that seems to work ok:

#+begin_src emacs-lisp
(defun fetch-image (url &optional destdir)
(url-retrieve
url
(lambda (status url destdir)
(let ((err (plist-get status :error)))
(if err
(signal :error (cdr err))))
(delete-region
(point-min)
(progn
(re-search-forward "^$" nil 'move)
(1+ (point))))
(write-file
(expand-file-name (file-name-nondirectory url) destdir)
(pop-to-buffer
(current-buffer)))) `(,url ,destdir) nil t))
#+end_src

rick