1 Commits
Author SHA1 Message Date
7a6bad29fe feat(display-controller): hot-reload plugin enable/disable without a restart (#374)
* feat(display-controller): hot-reload plugin enable/disable without a restart

Enabling or disabling a plugin in config previously required restarting the
display service: the plugin list and available_modes were built once at init
and the run loop never revisited them. (Per-plugin config *values* already
hot-reloaded; only the enabled set was restart-only.)

Now the controller reconciles its running plugins against the config's enabled
set whenever that set changes:

- The ConfigService watcher thread only sets a `_pending_plugin_reconcile`
  flag (via a cheap enabled-set diff). It never mutates loop state.
- The run loop applies the reconcile on its own thread (top of each
  iteration, deferred while on-demand is active), so loading/unloading and
  rebuilding available_modes can't race with rendering.
- `_reconcile_enabled_plugins` diffs desired vs running plugins, unloads the
  removed ones (cleanup + on_disable + config-unsubscribe via the new
  `_unregister_plugin`) and loads the added ones, then clamps the rotation
  index so the current mode stays valid.

The per-plugin registration done at startup is extracted into
`_register_loaded_plugin` and reused by the live-enable path so both build
identical state. Extracting it also fixes a latent late-binding bug: the
per-plugin config-change callbacks were closures over the loop variable, so
every plugin's callback targeted the last-loaded instance; each now binds its
own id/instance.

Adds test/test_display_controller_plugin_toggle.py covering live enable,
live disable, index clamping, no-op when unchanged, and the enabled-set diff.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* fix(display-controller): don't exit on empty available_modes, guard rotation modulo

Hot-reload means available_modes can legitimately be empty at startup (no
plugins enabled yet) and become non-empty later via the web UI, or vice
versa mid-run. Fix four issues found reviewing this PR:

- run() exited the process entirely when available_modes was empty at
  startup instead of idling, permanently defeating the point of live
  enable/disable for anyone who starts with zero plugins enabled.
- The mode-rotation step divided by len(available_modes) unconditionally,
  raising ZeroDivisionError if the last enabled plugin is disabled between
  frames.
- _reconcile_enabled_plugins() called .get('enabled', False) on a config
  section without checking it was a dict first, raising AttributeError on
  a malformed config value.
- Minor: pop the config-change callback only after attempting to
  unsubscribe it, and log the exception in the config-read fallback
  instead of swallowing it silently.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KEZK1P1Q1fu5pcuVrkrCFZ

* fix(display-controller): address review findings on the hot-reload PR

- Idle-wait tick was a fixed 30s sleep, delaying pickup of a plugin
  enabled via the web UI while no modes were active. Shortened to ~1s so
  it's roughly as responsive as the per-frame check once modes exist.
- _unregister_plugin popped the config-change callback from
  _plugin_config_callbacks even when config_service.unsubscribe() raised,
  losing the only reference to it. Now only pops on a successful
  unsubscribe.
- _pending_plugin_reconcile was cleared before _reconcile_enabled_plugins()
  ran, so a retryable failure (e.g. plugin discovery erroring) silently
  dropped the enable/disable request. _reconcile_enabled_plugins() now
  returns True/False and the caller only clears the flag on True.
- Added a warning log for the malformed-config case (a plugin's config
  section present but not a dict) so it's actually visible, and updated
  the existing test to assert it via caplog.

Left the broad `except Exception` around config_service.unsubscribe() as
Exception -- the current implementation is a simple lock+dict/list op that
doesn't document or realistically raise a narrower type, so this is a
defensive catch-all, not user error handling.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KEZK1P1Q1fu5pcuVrkrCFZ

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Co-authored-by: ChuckBuilds <charlesmynard@gmail.com>
2026-07-06 17:37:01 -04:00