Server Monitor

Home Assistant custom integration for monitoring the home server "megalageret" (OMV-based). Provides a sidebar panel and a compact mobile card showing power/energy, RAM/GPU, disk health, Docker containers, OMV services, and server actions (reboot/shutdown/prune).

Architecture

• custom_components/server_monitor/ — the integration itself:
  • __init__.py — sets up the config entry, registers the frontend static path and sidebar panel, forwards sensor platform setup.
  • coordinator.py — DataUpdateCoordinator that polls (every 30s) whether the ~70 entities the frontend depends on (owned by other integrations: OMV, energy meter, Docker container sensors, ...) are present and available. It does not fetch server metrics itself.
  • sensor.py — exposes sensor.server_monitor_entity_health, a diagnostics sensor reporting how many monitored entities are missing/unavailable.
  • const.py — includes MONITORED_ENTITIES, the list of entity IDs the frontend depends on. Kept in sync manually with the frontend JS files, which read the same entities directly via hass.states for rendering.
  • frontend/ — server-monitor-shared.js (single source of truth for entity IDs + value/health helpers, loaded via dynamic import()), server-monitor-panel.js (full sidebar panel) and server-monitor-card.js (compact card), served as static files.
• packages/server_monitor.yaml — HA template sensors: Docker running/total container counts, monthly kWh, and monthly cost (fixed average price, not live spot price — see comments in the file for why).

Design notes

• Color palette: sky/indigo (--accent: #38bdf8, --accent2: #818cf8).
• The integration does not own or poll the server's actual metrics (disk, CPU, GPU, network) — those come entirely from the OMV integration and are read directly by the frontend. The coordinator's role is entity-health monitoring, not data collection.

Known limitations

• The list of entity IDs the panel depends on is hardcoded in both const.py (for health checks) and frontend/server-monitor-shared.js (for rendering, shared between panel and card). If OMV or another integration renames an entity, both places need updating.
• The panel/card are served via js_url (classic script), not module_url, so server-monitor-shared.js is loaded via dynamic import() at runtime rather than a static import statement at the top of the file. This works in all modern browsers but means the shared module loads asynchronously on first render (a loading spinner covers this gap — see CHANGELOG 1.3.0).