infoscreen-dev/CHANGELOG.md

Changelog

April 2026

Remote Command Intake

• Added MQTT command intake on infoscreen/{client_id}/commands (supports reboot and shutdown).
• Added command acknowledgement publishing to infoscreen/{client_id}/commands/ack and infoscreen/{client_id}/command/ack with states accepted, rejected, execution_started, completed, failed.
• Added COMMAND_HELPER_PATH environment variable; command execution delegated to an external shell helper so simclient.py requires no elevated privileges.
• Added deduplication of commands by command_id with configurable TTL (COMMAND_DEDUPE_TTL_HOURS) and max-entries cap (COMMAND_DEDUPE_MAX_ENTRIES).
• Added execution timeout (COMMAND_EXEC_TIMEOUT_SEC).
• Added COMMAND_MOCK_REBOOT_IMMEDIATE_COMPLETE flag for canary and test environments — immediately completes a mock reboot without waiting for process restart. Safety-guarded: only activates when the helper basename is mock-command-helper.sh.

MQTT Broker Authentication Split

• Split broker connection credentials (MQTT_USER, MQTT_PASSWORD_BROKER) from legacy per-device identity fields (MQTT_USERNAME, MQTT_PASSWORD).
• configure_mqtt_security() now prefers MQTT_USER/MQTT_PASSWORD_BROKER for broker login, with fallback to legacy vars if broker-specific vars are absent.

Systemd Service Units

• Added scripts/infoscreen-simclient.service — systemd unit for simclient.py with Type=notify, WatchdogSec=60, Restart=on-failure, StartLimitBurst=5.
• Added scripts/start-simclient.sh — launcher script mirroring start-display-manager.sh.
• Updated scripts/infoscreen-display.service with OnFailure=infoscreen-notify-failure@%n.service.
• Updated src/pi-setup.sh to install and enable both units plus the failure notifier template.

Process Watchdog (Gap 1 — Hung Process Detection)

• Added zero-dependency _sd_notify() raw socket helper in simclient.py (no systemd-python package required).
• Sends READY=1 on main loop entry and WATCHDOG=1 on every 5-second iteration.
• Service unit uses Type=notify and WatchdogSec=60; systemd will restart the process if it stops sending keepalives for 60 seconds.

OnFailure MQTT Notifier (Gap 3 — systemd Give-Up Detection)

• Added scripts/infoscreen-notify-failure@.service — systemd template unit triggered by OnFailure=.
• Added scripts/infoscreen-notify-failure.sh — publishes a retained JSON payload to infoscreen/{uuid}/service_failed via mosquitto_pub so the monitoring dashboard gets an alert even when the process is fully dead.
• Payload: {"event":"service_failed","unit":"<unit-name>","client_uuid":"...","failed_at":"<ISO-UTC>"}.

Health Payload Broker Connection Block (Gap 2 — Broker vs. Process Ambiguity)

• Added broker_connection block to the health payload: broker_reachable, reconnect_count, connect_count, last_disconnect_at.
• simclient.py now tracks reconnect_count and connect_count on every on_connect callback and last_disconnect timestamp on on_disconnect.
• publish_health_message() accepts an optional connection_state parameter; both heartbeat-success call sites pass the enriched state.

TV Power Coordination

• Added Phase 1 TV power coordination on infoscreen/groups/{group_id}/power/intent.
• Added POWER_CONTROL_MODE with local, hybrid, and mqtt behavior.
• Added src/power_intent_state.json and src/power_state.json for power IPC and telemetry.
• Added infoscreen/{client_id}/power/state publishing from simclient.py.
• Added turn-off guard logic to avoid unintended TV-off races at event boundaries.
• Added TV_POWER_RUNBOOK.md and test tooling in scripts/test-power-intent.sh.

March 2026

• Hardened event-trigger screenshots (event_start, event_stop) against periodic overwrite races.
• Improved latest.jpg and meta.json synchronization for reliable dashboard updates.
• Added self-healing for stale or invalid pending screenshot trigger metadata.
• Improved display environment fallbacks (DISPLAY=:0, XAUTHORITY) for non-interactive starts.
• Allowed periodic idle captures in development mode so dashboard previews stay fresh without active events.
• Added content-type-aware trigger delays for event screenshots.
• Changed screenshot transmission to a 1-second polling tick so triggered sends fire within <=1s.
• Migrated dashboard payload to grouped schema v2 (message, content, runtime, metadata).

November 2025

• Implemented the two-process screenshot pipeline (display_manager.py capture, simclient.py transmission).
• Added Wayland/X11 screenshot tool fallback chains.
• Extended dashboard payloads with screenshot and system metadata.
• Extended scheduler event type support for presentation, webuntis, webpage, and website.
• Added website autoscroll support via CDP injection and extension fallback.