Canonical entity graph, parent/child hierarchy, raw entity state, element-to-property relations, and local computed projection.
Owns
- entity create/remove/update, hierarchy, order, identity, and serialization
- element-slot-to-root-property relations and reverse indexes
- batch-only local computed projection and ordinary computed events
- prepared/apply boundaries for atomic insertion, removal, move, and subtree lifecycle
Does not own
Property definitions/child graphs, UI policy, render objects, app Group command meaning, or computed data as canonical/shared/history/persisted state.
Compose when
Compose it for canonical entity/hierarchy products. Core already coordinates it for app use. Do not use Scene Tree for a pure global managed-property model or as a render display list.
Public entrypoints and prerequisites
Use @asyra/scene-tree or Core's curated facades. Public owner surfaces include entity/hierarchy operations, component relations, prepared canonical mutations, load validation/apply, local computed update/patch/projection, and subtree move/remove/restore contracts. Property roots must be registered with Props Manager.
Lifecycle, inputs, outputs, and failure
Every batch validates ids, membership, relations, parent slot, cycle, order, and staleness before first mutation. Owner-issued prepared artifacts are one-shot and instance-bound. Valid apply emits ordered canonical evidence; local computed projection emits no history/publication/persistence. Invalid or stale operations fail without a map, hierarchy, relation, or history prefix.
Relationships
Props Manager owns property values/graphs. Core coordinates atomic cross-owner work. Factory records owner evidence. Render/UI consume computed projections. Preset supplies official Group defaults/adapters; the app owns product command policy.
Maintained use path
Use Build a custom component and schema for component relations, then follow Build hierarchy and Group behavior for the generated app's formal hierarchy route.
Replacement and disabled behavior
Apps may register custom components/containers and bypass Preset Group defaults, but canonical hierarchy still belongs to Scene Tree. Local computed projection may be replaced/rebuilt without changing canonical data. Without Scene Tree, entity hierarchy APIs are unavailable rather than emulated in UI state.
Support, migration, and deprecation
Current Group hierarchy supports deterministic move/reorder/subtree lifecycle, rollback, replay, load, and collaboration evidence. Migration must preserve identity, parent/index/order, relations, and separation of canonical versus computed data. Direct map/parent mutation is unsupported.
Canonical sources and release inventory
The root entrypoint, version, and dependencies are generated from the manifest and validated against the release inventory.