5.4.0 Change Notes

• [5.4.0 Change Notes](#5.4.0 Change Notes)
  • Node.js 24 support
  • Frontend
    • QuantityFormatter
      • Updated migration guidance from QuantityType to KindOfQuantity
  • Presentation changes
  • API deprecations
    • @itwin/presentation-common
  • Incremental Schema Loading

Node.js 24 support

In addition to already supported Node.js versions, iTwin.js now supports Node.js 24.

Frontend

QuantityFormatter

The QuantityFormatter has been updated to use new schema references for KindOfQuantity definitions. This change aligns with the introduction of DefaultToolsUnits and CivilUnits schemas, providing more appropriate categorization for different types of measurements used in tools and applications.

• QuantityFormatter:
  • Internal QuantityTypeFormatsProvider has been updated to map to the new schemas
  • Added support for AecUnits.LENGTH for engineering-specific length measurements, particularly imperial formatting using fractional precision (e.g 5 ft 1/4 in)

Updated migration guidance from QuantityType to KindOfQuantity

For developers using QuantityType enum values in their applications, no code changes are required as the mapping to the new schemas is handled internally. However, for domain agnostic tools directly using KindOfQuantity names or implementing custom property descriptions, update your code to reference the new schema names.

For detailed information about the recommended KindOfQuantity to use in your tools and components, including a complete mapping table of measurements to their corresponding KindOfQuantity names and persistence units, see the Quantity Formatting and Parsing documentation.

Presentation changes

• Changed content traversal to have internal state, improving performance when traversing large contents. See API deprecations for @itwin/presentation-common for more details.

API deprecations

@itwin/presentation-common

• Deprecated traverseContent and traverseContentItem in favor of createContentTraverser factory function. The change allows caching some state between calls to traverser methods, improving performance when traversing large contents.

  Migration example:

  // before traverseContent(myVisitor, content); // ... or content.contentSet.forEach((item) => traverseContentItem(myVisitor, content.descriptor, item)); // now const traverseContentItems = createContentTraverser(myVisitor, content.descriptor); traverseContentItems(content.contentSet); // ... or const traverseContent = createContentTraverser(myVisitor); traverseContent(content.descriptor, content.contentSet);

Incremental Schema Loading

Incremental Schema Loading support has been added to the backend on IModelDb and IModelConnection on frontends.

Clients can control how the schemas are loaded through their application context, using the incrementalSchemaLoading option when initializing their IModelHost or IModelApp. By default, incremental schema loading is disabled, so clients have to enable this feature if they want to use it.

Incremental schema loading allows to load a schema partially. Clients can receive their schema and its elements while references and lazy loaded schema elements are loaded in the background.

• Frontend examples:

  await IModelApp.startup({ incrementalSchemaLoading: "enabled" });
  await IModelApp.startup({ incrementalSchemaLoading: "disabled" });

• Backend examples:

  await IModelHost.startup({ incrementalSchemaLoading: "enabled", });
  await IModelHost.startup({ incrementalSchemaLoading: "disabled", });