Add filter, add READMES

backend_go/selection_queries/subclasses.go

@@ -0,0 +1,55 @@
+package selection_queries
+
+import (
+	"context"
+	"fmt"
+	"strings"
+)
+
+func subclassesQuery(selectedNodes []NodeRef, includeBNodes bool) string {
+	valuesTerms := make([]string, 0, len(selectedNodes))
+	for _, n := range selectedNodes {
+		t := valuesTerm(n)
+		if t == "" {
+			continue
+		}
+		valuesTerms = append(valuesTerms, t)
+	}
+
+	if len(valuesTerms) == 0 {
+		return "SELECT ?nbr WHERE { FILTER(false) }"
+	}
+
+	bnodeFilter := ""
+	if !includeBNodes {
+		bnodeFilter = "FILTER(!isBlank(?nbr))"
+	}
+
+	values := strings.Join(valuesTerms, " ")
+	return fmt.Sprintf(`
+PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
+
+SELECT DISTINCT ?nbr
+WHERE {
+  VALUES ?sel { %s }
+  ?nbr rdfs:subClassOf ?sel .
+  FILTER(!isLiteral(?nbr))
+  FILTER(?nbr != ?sel)
+  %s
+}
+`, values, bnodeFilter)
+}
+
+func runSubclasses(ctx context.Context, q Querier, idx Index, selectedIDs []int, includeBNodes bool) ([]int, error) {
+	selectedNodes, selectedSet := selectedNodesFromIDs(idx, selectedIDs, includeBNodes)
+	if len(selectedNodes) == 0 {
+		return []int{}, nil
+	}
+
+	raw, err := q.Query(ctx, subclassesQuery(selectedNodes, includeBNodes))
+	if err != nil {
+		return nil, err
+	}
+	return idsFromBindings(raw, "nbr", idx, selectedSet, includeBNodes)
+}
+