[QUESTION] Re: [PATCH] make org-attach-url download function as an option

[stardiviner <numbchild@gmail.com>]

I got solution for async org-attach-url now. Use `make-thread` for async
downloading is simple.

Here is the code prototype, but it has a problem, seems `apply` part code does
not really downloading file. I don't know why. Does anybody knows the reason?

#+begin_src diff
modified   lisp/org-attach.el
@@ -110,6 +110,12 @@ (defcustom org-attach-method 'cp
 	  (const :tag "Hard Link" ln)
 	  (const :tag "Symbol Link" lns)))
 
+(defcustom org-attach-url-function 'url-copy-file
+  "The download file function to use in org-attach-url."
+  :type '(choice (const 'url-copy-file))
+  :safe #'functionp
+  :group 'org-attach)
+
 (defcustom org-attach-expert nil
   "Non-nil means do not show the splash buffer with the attach dispatcher."
   :group 'org-attach
@@ -503,7 +509,12 @@ (defun org-attach-attach (file &optional visit-dir method)
        ((eq method 'cp) (copy-file file attach-file))
        ((eq method 'ln) (add-name-to-file file attach-file))
        ((eq method 'lns) (make-symbolic-link file attach-file))
-       ((eq method 'url) (url-copy-file file attach-file)))
+       ((eq method 'url) (make-thread
+			  (lambda ()
+			    ;; (url-copy-file file attach-file)
+			    ;; FIXME This seems does not really download file. Don't know why.
+			    (apply org-attach-url-function '(file attach-file)))
+			  "org-attach-url downloading")))
       (run-hook-with-args 'org-attach-after-change-hook attach-dir)
       (org-attach-tag)
       (cond ((eq org-attach-store-link-p 'attached)
#+end_src

Bastien <bzg@gnu.org> writes:

> Hi,
>
> stardiviner <numbchild@gmail.com> writes:
>
>> I found when network is bad and slow, or the download file is big, the
>> org-attach-url will suspend Emacs for a long time. User might have to cancel
>> downloading, and start again later.
>
> Indeed, this might be annoying.  At the same time, it is not
> unreasonable to expect the user to know what size is the contents he
> is willing to attach to an Org node.
>
>> I hope to make "org-attach-url" download file asynchronously. But function
>> org-attach-attach hardcoded this function for 'url method. Here is a patch to
>> make it into an option.
>
> (FWIW, I could not find the patch.)
>
> I think you are on the right track when trying to enhance the 'url
> package.  Maybe url-copy-file should be asynchronous and url could
> provide url-copy-file-synchronously (to mimic the url-retrieve and
> url-retrieve-synchronously pair)?
>
> Until Emacs has a function to copy a URL's contents asynchronously,
> I'd rather not add this functionality in Org.


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[ stardiviner ]
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