Emacs as an Org capture server

Emacs-as-an-Org-capture-server.org

Emacs as an Org capture server

The Concept

The general idea is to run an Emacs server as a daemon which clients can quickly connect to via a bash script. The client executes org-capture and the frame closes upon finalizing or aborting the capture.

Running a server daemon

The first step is to get an Emacs daemon running as a server with your name of choice. For this example, I’m going to use “capture” as the server name.

From your terminal start the server daemon and give it a name

emacs --daemon="capture"

Running a client

You can connect to this server with a client by launching Emacs from the terminal with the following arguments:

emacsclient --create-frame \
            --socket-name 'capture' \
            --alternate-editor='' \
            --no-wait

We’ll make a script out of this and add more args after we set up things on the Elisp side.

Elisp setup

In your init.el file (or in a separate package if you like) define the functions that make this server’s clients run org-capture and close.

my/delete-capture-frame

This function deletes the frame after you finalize a capture:

(defun my/delete-capture-frame (&rest _)
  "Delete frame with its name frame-parameter set to \"capture\"."
  (if (equal "capture" (frame-parameter nil 'name))
      (delete-frame)))
(advice-add 'org-capture-finalize :after #'my/delete-capture-frame)

my/org-capture-frame

This function is a modernized version of the info found here:

• http://cestlaz.github.io/posts/using-emacs-24-capture-2/
• https://stackoverflow.com/questions/23517372/hook-or-advice-when-aborting-org-capture-before-template-selection

This function runs when creating a new client. It selects the correct frame and forces org-capture to show the template selection menu in the main window instead of splitting it. It also closes the frame if you abort the capture process.

(defun my/org-capture-frame ()
  "Run org-capture in its own frame."
  (interactive)
  (require 'cl-lib)
  (select-frame-by-name "capture")
  (delete-other-windows)
  (cl-letf (((symbol-function 'switch-to-buffer-other-window) #'switch-to-buffer))
    (condition-case err
        (org-capture)
      ;; "q" signals (error "Abort") in `org-capture'
      ;; delete the newly created frame in this scenario.
      (user-error (when (string= (cadr err) "Abort")
                    (delete-frame))))))

Now you can flesh out the emacsclient command from earlier to run your dedicated org-capture server:

#!/bin/bash
emacsclient --create-frame \
            --socket-name 'capture' \
            --alternate-editor='' \
            --frame-parameters='(quote (name . "capture"))' \
            --no-wait \
            --eval "(my/org-capture-frame)"

You can bind this script to a global keybinding and you should be able to capture from ‘outside’ Emacs via that binding.

Nice! I did an small shell script SPC to send keyboard macros to my emacs precisely for org-capturing, but I was missing this auto-close-frame bit. adding the after advice to org-capture-finalize. Thanks for sharing, will add something like this on my env.