A sudo org-link and sh block

Fri, 17 Jul 2015 12:42:34 EDT

Shell blocks in org-mode are pretty useful, but they are a little limited in that it is not obvious how to run a sudo command in them.

So for example, this gives me a permission denied error.

ls /var/audit

One way to get around this is to create an org-mode link like this one:

;http://stackoverflow.com/questions/2472273/how-do-i-run-a-sudo-command-in-emacs
(org-add-link-type
 "sudo"
 (lambda (cmd)
   "Run CMD with sudo."
   (shell-command
    (concat "echo " (shell-quote-argument (read-passwd "Password? "))
            " | sudo -S " cmd))))

Now you can create a link like ls /var/audit, and when you click on it you will be prompted for a password, and then you will see a buffer containing the output. To get an actual sudo code block, you need a new org babel library. Here is an example of what it might look like. Tangle this file to generate the library. Note: This is a lightly modified version of ob-emacs-lisp.el, and I have not tested it very thoroughly.

;;; ob-sudo.el --- An org-mode source block to run shell commands as sudo

;;; Commentary:
;; Runs the block of code as a shell command with sudo.

;;; Code:

(defun org-babel-execute:sudo (body params)
  "Run BODY as a shell command using sudo."
  (let* ((passwd (shell-quote-argument (read-passwd "Password? ")))
         (result (shell-command-to-string
                  (concat "echo " passwd
                          " | sudo -S " body))))
    ;; this is verbatim from ob-emacs-lisp
    (org-babel-result-cond (cdr (assoc :result-params params))
      (let ((print-level nil)
            (print-length nil))
        (if (or (member "scalar" (cdr (assoc :result-params params)))
                (member "verbatim" (cdr (assoc :result-params params))))
            (format "%S" result)
          (format "%s" result)))
      (org-babel-reassemble-table
       result
       (org-babel-pick-name (cdr (assoc :colname-names params))
                            (cdr (assoc :colnames params)))
       (org-babel-pick-name (cdr (assoc :rowname-names params))
                            (cdr (assoc :rownames params)))))))

(provide 'ob-sudo)
;;; ob-sudo.el ends here

Let us add the current dir to our path so we can load it. If you use this a lot, you should put the library on your permanent path.

(add-to-list 'load-path (expand-file-name "."))

Now, add the sudo "language" to org-babel-load-languages.

(org-babel-do-load-languages
 'org-babel-load-languages
 '((emacs-lisp . t)
   (python . t)
   (sh . t)
   (matlab . t)
   (sqlite . t)
   (ruby . t)
   (perl . t)
   (org . t)
   (dot . t)
   (plantuml . t)
   (R . t)
   (sudo . t)))

And, here it is in action. Hopefully I am not giving away some important information here!

ls /var/audit

20141106003522.20141110021519
20141110021548.crash_recovery
20141112154126.crash_recovery
20141119201541.20141122145259
20141122145317.20141124214930
20141124215000.crash_recovery
20141126062011.20141202192451
20141202192507.crash_recovery
20141210133306.crash_recovery
20141225181819.20150106015256
20150106015325.20150111010018
20150111010121.crash_recovery
20150115195518.20150115200101
20150115200110.crash_recovery
20150123061227.20150215123411
20150215123454.crash_recovery
20150225004740.20150310201600
20150310201633.20150314214730
20150314214807.crash_recovery
20150323145600.20150329170647
20150329170721.crash_recovery
20150407215846.20150413000423
20150413000438.20150421122044
20150421122104.20150518122545
20150518122616.20150518124432
20150518124432.20150518124513
20150518124513.20150518125437
20150518125437.20150518125935
20150518125935.20150518132111
20150518132111.20150531202621
20150531202719.20150601123612
20150601123612.20150601124932
20150601124932.20150601125151
20150601125151.20150601125555
20150601125555.20150601131947
20150601131947.20150601132421
20150601132421.20150601133735
20150601133735.20150601140740
20150601140740.20150601154012
20150601154012.20150601155125
20150601155125.20150601155215
20150601155215.20150601160937
20150601160937.crash_recovery
20150613061543.20150614054541
20150614054541.20150625165357
20150625165432.20150625200623
20150625200623.20150628042242
20150628042242.20150628103628
20150628103628.20150630052100
20150630052100.20150701232519
20150702005345.20150710203212
20150710203226.not_terminated
current

Summary thoughts: I will reiterate again I have not tested this a lot, I was mostly interested in trying to make a new sh block with sudo support. Let me know if it has issues for you, and make sure you have backups of things it could mess up!

org-mode source

Org-mode version = 8.2.10

The Kitchin Research Group

A sudo org-link and sh block