IDS Validation

IFClite supports IDS (Information Delivery Specification), the buildingSMART standard for defining and validating information requirements in BIM models. The @ifc-lite/ids package implements IDS 1.0 with full facet and constraint support.

What is IDS?

IDS allows you to define specifications that describe what information an IFC model should contain. Each specification has:

• Applicability - Which entities the rule applies to (e.g., all walls)
• Requirements - What information those entities must have (e.g., fire rating property)

Validation checks every applicable entity against the requirements and produces a pass/fail report.

Quick Start

Parsing IDS Files

import { parseIDS } from '@ifc-lite/ids';

// Parse an IDS XML file
const idsDocument = parseIDS(idsXmlString);

console.log(`${idsDocument.info.title}`);
console.log(`${idsDocument.specifications.length} specifications`);

for (const spec of idsDocument.specifications) {
  console.log(`  ${spec.name}`);
}

Running Validation

The easiest way to validate a parsed model is the bridge, which builds the data accessor the validator needs directly from an IfcDataStore (the output of @ifc-lite/parser):

import { parseIDS, validateIDS } from '@ifc-lite/ids';
import { createDataAccessor } from '@ifc-lite/ids/bridge';
import type { IDSModelInfo } from '@ifc-lite/ids';

const idsDocument = parseIDS(idsXml);

// Bridge the parsed IFC data store to the validator
const accessor = createDataAccessor(dataStore);

// Model info for the validation report
const modelInfo: IDSModelInfo = {
  modelId: 'model.ifc',
  schemaVersion: 'IFC4',
  entityCount: dataStore.entityCount,
};

// Validate (requires: document, accessor, modelInfo, options?)
const report = await validateIDS(idsDocument, accessor, modelInfo, {
  onProgress: (progress) => console.log(`${progress.phase}: ${progress.percentage}%`),
});

console.log(`${report.summary.totalEntitiesChecked} entities checked`);
console.log(`${report.summary.totalEntitiesPassed} passed`);
console.log(`${report.summary.totalEntitiesFailed} failed`);

The bridge mirrors IfcOpenShell ifctester semantics (classification sub-reference walking, length unit conversion, predefined property-set unwrapping, schema-driven attribute types). It also exports narrowSchemaVersion for mapping a parsed schema string to an IDS IFCVersion.

Other options in ValidatorOptions: translator (see below), includePassingEntities (default true), and yieldEveryMs to keep the thread responsive on large models.

Custom Data Sources

If your IFC data does not come from @ifc-lite/parser, implement the IFCDataAccessor interface yourself. It requires getAllEntityIds, getEntitiesByType, getEntityType, getEntityName, getGlobalId, getDescription, getObjectType, getPropertyValue, getPropertySets, getClassifications, getMaterials, getParent, and getAttribute, plus optional methods (getAncestors, getAttributeNames, getAttributeXsdTypes, getPredefinedTypeRaw) that improve spec fidelity when provided.

Facet Types

IDS supports six facet types for defining applicability and requirements:

Facet	Description	Example
Entity	Match by IFC type	IFCWALL, IFCDOOR
Attribute	Match by IFC attribute	Name = "W-042"
Property	Match by property set/property	Pset_WallCommon.FireRating
Classification	Match by classification system	Uniclass 2015: Ss_25_10
Material	Match by material name	Concrete C30/37
PartOf	Match by spatial containment	IfcBuildingStorey "Level 1"

Constraint Types

Each facet can use different constraint types to match values:

Constraint	Description	Example
Simple	Exact value match	"REI 120"
Pattern	Regex pattern match	"REI \\d+"
Enumeration	One of several values	["REI 60", "REI 90", "REI 120"]
Bounds	Numeric range	>= 0.2 AND <= 0.5

Multi-Language Support

Validation reports can be generated in multiple languages:

import { createTranslationService } from '@ifc-lite/ids';

const t = createTranslationService('de'); // German
// Or: 'en' (English, default), 'fr' (French)

// Pass it to validateIDS to translate the report:
const report = await validateIDS(idsDocument, accessor, modelInfo, { translator: t });

Auditing IDS Documents

Beyond validating models, the package can audit the IDS document itself for structural and semantic problems:

import { auditIDSDocument } from '@ifc-lite/ids';

// Takes the raw IDS XML (string or ArrayBuffer); parse errors become structured issues
const auditReport = await auditIDSDocument(idsXml);

Use auditIDSStructure(idsDocument) to audit an already-parsed document.

Viewer Integration

In the IFClite viewer, IDS validation is integrated through the IDS panel:

1. Load IDS - Drag and drop an .ids XML file
2. Run Validation - Click validate to check the loaded model(s) against IDS rules
3. Browse Results - View pass/fail per specification and per entity
4. 3D Highlighting - Failed entities are highlighted in red in the 3D view
5. Filter - Show all entities, only failed, or only passed
6. Navigate - Click a failed entity to zoom to it in 3D
7. Export BCF - Turn validation failures into BCF topics (see BCF)

Validation runs in a Web Worker so the UI stays responsive during large runs, with an automatic fallback to in-process validation if the worker is unavailable.

Display Options

Option	Default	Description
Highlight failed	On	Red highlight on failed entities in 3D
Highlight passed	Off	Green highlight on passed entities in 3D
Filter mode	All	Show all, failed only, or passed only
Locale	Auto	Language for validation messages (EN/DE/FR)

Key Types

Type	Description
IDSDocument	Parsed IDS file with info and specifications
IDSSpecification	A single validation rule with applicability and requirements
IDSFacet	Entity, Attribute, Property, Classification, Material, or PartOf
IDSConstraint	Simple, Pattern, Enumeration, or Bounds value matcher
IDSValidationReport	Complete validation results with per-entity details
IDSEntityResult	Pass/fail result for a single entity with failure details