feat: add variablemeasured facet type for schema:variableMeasured/PropertyValue search

client/public/config/config_ecoforcast.yaml

@@ -106,6 +106,11 @@ FACETS:
     sort: acs
     open: true
     type: range
+  - field: variableMeasured
+    title: Variables Measured
+    sort: acs
+    open: true
+    type: propertyvalue
 ORDER_BY_DEFAULT: score
 ORDER_BY_OPTIONS:
   - field: name

client/public/config/config_qlever.yaml

@@ -128,11 +128,11 @@ FACETS:
     sort: acs
     open: true
     type: rangeyear
-#  - field: variableMeasured
-#    title: Variables Measured
-#    sort: acs
-#    open: true
-#    type: text
+  - field: variableMeasured
+    title: Variables Measured
+    sort: acs
+    open: true
+    type: propertyvalue
 ORDER_BY_DEFAULT: score
 ORDER_BY_OPTIONS:
   - field: name

client/src/services/SearchService.js

@@ -278,10 +278,6 @@ SELECT ?value (0 as ?count) WHERE { FILTER(false) } LIMIT 0
       resourceType = '',
     } = searchContext;
 
-    const sparqlProperty =
-      facetConfig.sparql_property ||
-      this.queryBuilder.getDefaultSparqlProperty(field);
-
     // Exclude this facet's own filters to avoid self-filtering options
     const filtersCopy = { ...(currentFilters || {}) };
     delete filtersCopy[field];
@@ -297,7 +293,14 @@ WHERE {
       resourceType,
       filtersCopy
     );
-    q += this.queryBuilder.buildFacetPropertyPattern(field, sparqlProperty);
+    if (facetConfig.type === 'variablemeasured' || facetConfig.type === 'propertyvalue') {
+      q += this.queryBuilder.buildPropertyValueNamePattern(field, facetConfig);
+    } else {
+      const sparqlProperty =
+        facetConfig.sparql_property ||
+        this.queryBuilder.getDefaultSparqlProperty(field);
+      q += this.queryBuilder.buildFacetPropertyPattern(field, sparqlProperty);
+    }
     q += `}
 GROUP BY ?value
 ORDER BY DESC(?count) ?value

client/src/services/SparqlQueryBuilder.js

@@ -437,6 +437,10 @@ ${inner}
         case 'text':
           fragments += this.buildTextFilter(field, Array.isArray(values) ? values : [values], facetConfig);
           break;
+        case 'variablemeasured':
+        case 'propertyvalue':
+          fragments += this.buildPropertyValueNameFilter(field, Array.isArray(values) ? values : [values], facetConfig);
+          break;
         case 'range':
         case 'rangeyear':
         case 'rangedepth':
@@ -758,6 +762,49 @@ ${typeValues}${typeFilter}${textFilters}${rangeConstraints}    }
     return { north: n, south: s, east: e, west: w };
   }
 
+  /**
+   * Generic filter for any schema property that points to a PropertyValue node,
+   * matching on schema:name using CONTAINS (case-insensitive).
+   *
+   * The SPARQL property path is taken from facetConfig.sparql_property; it defaults
+   * to schema:variableMeasured so that "variableMeasured" facets work out of the box.
+   * Other PropertyValue relationships (e.g. schema:measurementTechnique) can be
+   * supported by adding a new facet entry in config with the desired sparql_property.
+   *
+   * Values are sanitized via escapeValue (backslash and double-quote escaping).
+   */
+  buildPropertyValueNameFilter(field, values, facetConfig) {
+    if (!Array.isArray(values) || values.length === 0) return '';
+    const pvProperty =
+      facetConfig?.sparql_property || 'schema:variableMeasured|sschema:variableMeasured';
+    const nodeVar = `${field}_pv`;
+    const typeVar = `${field}_pvType`;
+    const nameVar = `${field}_pvName`;
+    const containsExprs = values
+      .map(v => `CONTAINS(LCASE(STR(?${nameVar})), LCASE("${this.escapeValue(v)}"))`)
+      .join(' || ');
+    return `  ?subj ${pvProperty} ?${nodeVar} .
+  VALUES ?${typeVar} { schema:PropertyValue sschema:PropertyValue }
+  ?${nodeVar} a ?${typeVar} .
+  ?${nodeVar} schema:name|sschema:name ?${nameVar} .
+  FILTER(${containsExprs}) .\n`;
+  }
+
+  /**
+   * Triple pattern that binds ?value to distinct PropertyValue names for facet option lists.
+   * Uses facetConfig.sparql_property (defaults to schema:variableMeasured).
+   */
+  buildPropertyValueNamePattern(field, facetConfig) {
+    const pvProperty =
+      facetConfig?.sparql_property || 'schema:variableMeasured|sschema:variableMeasured';
+    const nodeVar = `${field}_pv_opt`;
+    const typeVar = `${field}_pvType_opt`;
+    return `  ?subj ${pvProperty} ?${nodeVar} .
+  VALUES ?${typeVar} { schema:PropertyValue sschema:PropertyValue }
+  ?${nodeVar} a ?${typeVar} .
+  ?${nodeVar} schema:name|sschema:name ?value .\n`;
+  }
+
   buildGenericFilter(field, values, facetConfig) {
     const sparqlProperty = facetConfig.sparql_property || this.getDefaultSparqlProperty(field);
     if (!Array.isArray(values) || values.length === 0) return '';