Add directory group resolver adapters

internal/adapters/directory/enrichment.go

@@ -0,0 +1,96 @@
+package directory
+
+import (
+	"sort"
+
+	"github.com/netkingdom/flex-auth/pkg/api"
+)
+
+// MergeResults combines resolver results while keeping source metadata.
+func MergeResults(subject api.SubjectRef, results ...ResolveResult) SubjectEnrichment {
+	groups := map[string]struct{}{}
+	roles := map[api.CanonicalRole]struct{}{}
+	metadata := map[string]any{}
+	enrichment := SubjectEnrichment{
+		Subject:  subject,
+		Metadata: metadata,
+	}
+
+	for _, result := range results {
+		for _, group := range result.Groups {
+			groups[group.ID] = struct{}{}
+			if group.Descriptor != nil {
+				enrichment.Descriptors = append(enrichment.Descriptors, *group.Descriptor)
+			}
+		}
+		for _, role := range result.Roles {
+			roles[role.Role] = struct{}{}
+		}
+		if !result.Freshness.RetrievedAt.IsZero() || result.Freshness.Source != "" {
+			enrichment.Freshness = append(enrichment.Freshness, result.Freshness)
+		}
+		if result.Overage.Detected {
+			enrichment.Overage = append(enrichment.Overage, result.Overage)
+		}
+		if result.Source != "" {
+			metadata["source:"+string(result.Source)] = true
+		}
+	}
+
+	enrichment.Groups = sortedStringKeys(groups)
+	enrichment.Roles = sortedRoleKeys(roles)
+	return enrichment
+}
+
+// ApplyToSubject returns a subject with resolved groups, roles, and metadata.
+func ApplyToSubject(subject api.Subject, enrichment SubjectEnrichment) api.Subject {
+	out := subject
+	out.Groups = mergeStrings(out.Groups, enrichment.Groups)
+	out.Roles = mergeRoles(out.Roles, enrichment.Roles)
+	if out.Metadata == nil {
+		out.Metadata = map[string]any{}
+	}
+	out.Metadata["directory_freshness"] = enrichment.Freshness
+	out.Metadata["directory_overage"] = enrichment.Overage
+	return out
+}
+
+func mergeStrings(a, b []string) []string {
+	items := map[string]struct{}{}
+	for _, value := range a {
+		items[value] = struct{}{}
+	}
+	for _, value := range b {
+		items[value] = struct{}{}
+	}
+	return sortedStringKeys(items)
+}
+
+func mergeRoles(a, b []api.CanonicalRole) []api.CanonicalRole {
+	items := map[api.CanonicalRole]struct{}{}
+	for _, value := range a {
+		items[value] = struct{}{}
+	}
+	for _, value := range b {
+		items[value] = struct{}{}
+	}
+	return sortedRoleKeys(items)
+}
+
+func sortedStringKeys(items map[string]struct{}) []string {
+	keys := make([]string, 0, len(items))
+	for key := range items {
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+	return keys
+}
+
+func sortedRoleKeys(items map[api.CanonicalRole]struct{}) []api.CanonicalRole {
+	keys := make([]api.CanonicalRole, 0, len(items))
+	for key := range items {
+		keys = append(keys, key)
+	}
+	sort.Slice(keys, func(i, j int) bool { return keys[i] < keys[j] })
+	return keys
+}