multiple org-roam notebases

Table of Contents

multiple org-roam notebases could be implemented in 2 seperate measures:

Those 2 works seperately and are both nice to have.

1. Objective: overload org-roam-directory and org-roam-db-location

These 2 are used to refer to the nodebases

  • org-roam-directory is the root directory of the notebase, which would be scanned when org-roam-db-sync is called and create a sqlite db for search
  • org-roam-db-location points to the db used to search your notes. If you manually set org-roam-directory to another dir, say from ~/main/ to ~/project/robotics/ , and did not run org-roam-db-sync, your org-roam-node-find would return nodes from ~/main/ but not ~/project/robotics/

2. .dir-locals.el

Place a .dir-locals.el file with the following content to the root of the project notebase(in here ~/project/robotics/): 

((nil . ((org-roam-directory . "~/project/robotics/") ;;don't forget the trailing "/", otherwise
;;org-roam-node-find would not find anything
         (org-roam-db-location . "~/project/robotics/org-roam.db")
         (org-roam-node-display-template . "${title} ${doom-type:12} ${doom-tags:42}")
                )))
on org-roam-node-display-template

I tend to use a large notes.org file with headings and luhmann id structure to organize project notes, so titles get very long if use doom-hierarchy if the id be 1b2a3 (displaying 1, 1b, 1b2 1b2a and 1b2a3 whell encoder)

effect
after setting up this file, each time you open a file under this directory, emacs would prompt you to load file-specific variables on our 2 objectives, and org-roam-node-find/insert would default to the directory, which makes sense: you’d want to visit zettels in the same zettelkasten.

3. overloading find and insert

The most frequently used zettelkasten primitives.

Here I used a messy wrapper function, whose job may be better done with macro. 

(setq org-roam-dirs
      '(("main"
         (org-roam-directory . "~/main/")
         (org-roam-db-location . "~/emacs-distros/doomemacs/.local/cache/org-roam.db")
         )
        ("comp329"
         (org-roam-directory . "~/projects/robotics/" )
         (org-roam-db-location . "~/projects/robotics/org-roam.db")))
      )
;; wrap org-roam-node-find and org-roam-node-insert

(defun hermanhelf-org-roam-multidir (func arg )
  (interactive "p")
  (cond
   ;; no prefix
   ((eq arg 1) (funcall func))
   ;; C-u
   ((eq arg 4) (let* ((profile (completing-read "org-roam note base" (mapcar 'car org-roam-dirs)))
                         (profile (car (-filter (lambda (item) (equal (car item) profile)) org-roam-dirs)))
                         (org-roam-directory (cdr (second profile)))
                         ;; (org-roam-db-location (cdr (third profile)))
                         )
                    (funcall func)
                    ;; org-roam-db-location

                    )
    )

   )
  )


(defun hermanhelf-org-roam-multidir-node-find (arg)
                      (interactive "p")
                      (hermanhelf-org-roam-multidir 'org-roam-node-find arg)
                )
(defun hermanhelf-org-roam-multidir-node-insert (arg)
                      (interactive "p")
                      (hermanhelf-org-roam-multidir 'org-roam-node-insert arg)
                )

(map! :map doom-leader-notes-map
      "r f"      #'hermanhelf-org-roam-multidir-node-find
                )
org-roam-dirs
store a list of directory, db location together with a string label. The format is almost trivial with the example above
hermanhel-org-roam-multidir func arg
is a wrapper function that calls func with a selected set of directory and db location when C-u prefix is pressed, and call it directly(which would conform to .dir-locals.el or global setting) when no prefix is provided.

Backlinks

In the old days this is the main way to go: to have a zettelkasten for each project, and according to wikipedia. Nowadays software make a lifelong main zettelkasten not as enormous, space consuming and labour heavy as they used to be, but project zettelkasten is still good practice.

org-roam

org-roam is a package implementing behaviours of a Zettelkasten note system into a specified org-roam-directory.

Author: Linfeng He

Created: 2024-04-03 Wed 20:17