backstage/.changeset/cyan-seahorses-film.md

@backstage/core-plugin-api

@backstage/core-plugin-api
minor

BREAKING CHANGE The StorageApi has received several updates that fills in gaps for some use-cases and makes it easier to avoid mistakes:

• The StorageValueChange type has been renamed to StorageValueSnapshot, the newValue property has been renamed to value, the stored value type has been narrowed to JsonValue, and it has received a new presence property that is 'unknown', 'absent', or 'present'.
• The get method has been deprecated in favor of a new snapshot method, which returns a StorageValueSnapshot.
• The observe$ method has had its contract changed. It should now emit values when the presence of a key changes, this may for example happen when remotely stored values are requested on page load and the presence switches from 'unknown' to either 'absent' or 'present'.

The above changes have been made with deprecations in place to maintain much of the backwards compatibility for consumers of the StorageApi. The only breaking change is the narrowing of the stored value type, which may in some cases require the addition of an explicit type parameter to the get and observe$ methods.