User area: clients overwrite each other's settings (last writer wins) #332

New issue

Closed

opened 2026-10-24 22:21:28 +00:00 by littlefox · 2 comments

littlefox commented

2026-10-24 22:21:28 +00:00

Owner

Interop audit, 2026-10-24.

The user area is last-writer-wins between clients, and a client can undo another's changes. The whole user area is one text, rewritten on every save.

NeoKOM (Kom::save_settings, kom.rs) writes the copy it read at login: our neokom block, plus the common block (Settings: read-depth-first, created-texts-are-read, presence-messages, language) and the elisp block (mute filters go into elisp's kom-filter-list when it has one). Anything changed elsewhere since login (in Emacs, or NeoKOM on another device) is lost on NeoKOM's next save. A save can be as small as following a thread or choosing a channel view.
Emacs client (lyskom-save-options, flags.el) keeps other clients' blocks, but from lyskom-other-clients-user-areas, read when its session started. "Spara inställningar" in Emacs writes back NeoKOM's block as it was then: followed threads, channel views and mute filters added since are lost.

Options:

NeoKOM re-reads before writing (recommended; NeoKOM-side only). Fetch the current user area, apply only the change being made, write. It removes NeoKOM-caused losses; the Emacs side stays as it is.
Don't write other clients' blocks: keep mute filters only in our block. Emacs then no longer applies them, but NeoKOM can't clobber Emacs's filters either.
Accept last-writer-wins, and say so in Settings.

Interop audit, 2026-10-24. **The user area is last-writer-wins between clients, and a client can undo another's changes.** The whole user area is one text, rewritten on every save. - **NeoKOM** (`Kom::save_settings`, `kom.rs`) writes the copy it read at login: our `neokom` block, plus the `common` block (Settings: read-depth-first, created-texts-are-read, presence-messages, language) and the `elisp` block (mute filters go into elisp's `kom-filter-list` when it has one). Anything changed elsewhere since login (in Emacs, or NeoKOM on another device) is lost on NeoKOM's next save. A save can be as small as following a thread or choosing a channel view. - **Emacs client** (`lyskom-save-options`, `flags.el`) keeps other clients' blocks, but from `lyskom-other-clients-user-areas`, read when its session started. "Spara inställningar" in Emacs writes back NeoKOM's block as it was then: followed threads, channel views and mute filters added since are lost. Options: 1. **NeoKOM re-reads before writing** (recommended; NeoKOM-side only). Fetch the current user area, apply only the change being made, write. It removes NeoKOM-caused losses; the Emacs side stays as it is. 2. **Don't write other clients' blocks:** keep mute filters only in our block. Emacs then no longer applies them, but NeoKOM can't clobber Emacs's filters either. 3. Accept last-writer-wins, and say so in Settings.

littlefox added the

kind/bug

area/protocol

needs/user

labels

2026-10-24 22:21:28 +00:00

littlefox commented

2026-10-28 08:50:39 +00:00

Author

Owner

Do option 1. People switching clients is not very common, but when they do we should show good etiquette.

littlefox removed the

needs/user

label

2026-10-28 08:50:46 +00:00

littlefox added this to the 0.8: Administration milestone

2026-10-28 09:08:41 +00:00

littlefox referenced this issue from a pull request that will close it,

2026-10-28 09:32:12 +00:00

Settings: re-read the user area before changing it #383

littlefox referenced this issue from a commit

2026-10-28 09:32:12 +00:00

Settings: re-read the user area before changing it

littlefox closed this issue

2026-10-28 10:11:31 +00:00

littlefox commented

2026-10-28 11:05:47 +00:00

Author

Owner

Merged in #383; main run #725 green. Every settings change now re-reads the user area and applies only that change (Kom::update_settings); saves from one session take turns. Verified by the devserver test user_area_changes_meet: two NeoKOM sessions with stale copies plus an Emacs-style write of elisp/common in between, and all changes survive. All 33 devserver tests pass. settings, mute and lock specs pass on all profiles.

Merged in #383; main run #725 green. Every settings change now re-reads the user area and applies only that change (`Kom::update_settings`); saves from one session take turns. Verified by the devserver test `user_area_changes_meet`: two NeoKOM sessions with stale copies plus an Emacs-style write of `elisp`/`common` in between, and all changes survive. All 33 devserver tests pass. settings, mute and lock specs pass on all profiles.