Replace org link description with org link output (shell type)

Question

I've stored several links to various shell commands and I would like to update each link description with the output of the correspoding shell command. For example:

View in text-mode: [[shell:echo "hello"][xxx]]
View in org-mode:  xxx

after running some post-processing function, I would get:

View in text-mode: [[shell:echo "hello"][hello​]]
View in org-mode:  hello

I know how to parse the different links and get the underlying shell command:

(org-element-map (org-element-parse-buffer) 'link
  (lambda (link)
    (when (string= (org-element-property :type link) "shell")
        (org-element-property :path link))))

but then I don't know how to modify the description using (org-element-context link)

Answer 1

The link description is the region in the buffer between the values of the properties contents-begin and contents-end:

#+begin_src emacs-lisp
(defun link-desc-region (link)
   (list (org-element-property :contents-begin link)
         (org-element-property :contents-end link)))

(defun replace-desc-in-link (link newdesc)
   (let ((region (link-desc-region link)))
       (goto-char (nth 0 region))
       (delete-region (nth 0 region) (nth 1 region))
       (insert newdesc))))
#+end_src

Evaluating (replace-desc-in-link (org-element-context) "hello") with point in the link should do what you want.