Cached unit data

Reading a unit's settings never sends anything to the unit. The gateway keeps every value a unit confirmed: when someone reads the unit's menu in the app, when a change is acknowledged, and when the unit reports it by itself. Such values carry source: "cache" and asOf (epoch milliseconds, when the unit last confirmed them); a value never confirmed is null.

The cache is stale only when the unit changed by itself: someone programmed it at the unit, it was reset, or it was replaced. Nothing else changes it behind the gateway's back.

So:

answer with "based on the last available data", and give asOf in plain words when it matters;
to refresh, the user opens the unit's page in the IGH app → Read menu (unit.menus);
a write is reported only after the unit acknowledged it, so the API never reports a value the unit didn't accept.

IGH home API 1.1.0. Generated from the doc source; do not edit.