Add namespace and collection inventories

internal/configuration/listing.go

@@ -6,6 +6,12 @@ import (
 	"gitea.maximumdirect.net/eric/promptkit/internal/domain"
 )
 
+// CollectionIdentity is the captured metadata for one final collection entry.
+type CollectionIdentity struct {
+	Namespace      string
+	ReleaseVersion *string
+}
+
 func (state *loaded) ListProfiles(ctx context.Context) ([]string, error) {
 	if err := ctx.Err(); err != nil {
 		return nil, err
@@ -28,6 +34,44 @@ func (state *loaded) ListBackends(ctx context.Context) ([]string, error) {
 	return backends, nil
 }
 
+func (state *loaded) ListNamespaces(ctx context.Context, kinds []string) ([]string, error) {
+	if err := ctx.Err(); err != nil {
+		return nil, err
+	}
+	selected := kinds
+	if len(selected) == 0 {
+		selected = []string{"backend", "profile", "prompt"}
+	}
+	set := make(map[string]struct{})
+	for _, kind := range selected {
+		for _, namespace := range state.namespaces[kind] {
+			set[namespace] = struct{}{}
+		}
+	}
+	namespaces := sortedKeys(set)
+	if err := ctx.Err(); err != nil {
+		return nil, err
+	}
+	return namespaces, nil
+}
+
+func (state *loaded) ListCollections(ctx context.Context) ([]CollectionIdentity, error) {
+	if err := ctx.Err(); err != nil {
+		return nil, err
+	}
+	collections := make([]CollectionIdentity, len(state.collections))
+	for index, collection := range state.collections {
+		collections[index] = CollectionIdentity{
+			Namespace:      collection.Namespace,
+			ReleaseVersion: stringPointerValue(collection.ReleaseVersion),
+		}
+	}
+	if err := ctx.Err(); err != nil {
+		return nil, err
+	}
+	return collections, nil
+}
+
 func (state *loaded) ListPrompts(ctx context.Context) ([]domain.PromptIdentity, error) {
 	if err := ctx.Err(); err != nil {
 		return nil, err

internal/configuration/load.go

@@ -127,6 +127,8 @@ type loaded struct {
 	backendIDs      []string
 	profileIDs      []string
 	promptIDs       []domain.PromptIdentity
+	namespaces      map[string][]string
+	collections     []CollectionIdentity
 }
 
 type resourceBases struct {
@@ -266,9 +268,38 @@ func load(main configkit.Input, underlays []configkit.Underlay) (*loaded, error)
 	for _, id := range sortedKeys(state.prompts) {
 		state.promptIDs = append(state.promptIDs, domain.PromptIdentity{ID: id, Version: stringPointerValue(state.prompts[id].definition.Version)})
 	}
+	state.namespaces = map[string][]string{
+		"backend": resourceNamespaces(state.backendIDs),
+		"profile": resourceNamespaces(state.profileIDs),
+		"prompt":  promptNamespaces(state.promptIDs),
+	}
+	for _, namespace := range sortedKeys(result.Config.Collections) {
+		collection := result.Config.Collections[namespace]
+		state.collections = append(state.collections, CollectionIdentity{
+			Namespace: namespace, ReleaseVersion: stringPointerValue(collection.ReleaseVersion),
+		})
+	}
 	return state, nil
 }
 
+func resourceNamespaces(ids []string) []string {
+	namespaces := make(map[string]struct{})
+	for _, id := range ids {
+		if namespace, _, qualified := strings.Cut(id, "/"); qualified {
+			namespaces[namespace] = struct{}{}
+		}
+	}
+	return sortedKeys(namespaces)
+}
+
+func promptNamespaces(prompts []domain.PromptIdentity) []string {
+	ids := make([]string, len(prompts))
+	for index := range prompts {
+		ids[index] = prompts[index].ID
+	}
+	return resourceNamespaces(ids)
+}
+
 func checkConfigurationVersion(version configkit.Version, validation *configkit.Validation) error {
 	if !version.Present {
 		return nil

internal/engine/engine.go

@@ -97,6 +97,8 @@ type identityInventory interface {
 	ListBackends(context.Context) ([]string, error)
 	ListProfiles(context.Context) ([]string, error)
 	ListPrompts(context.Context) ([]domain.PromptIdentity, error)
+	ListNamespaces(context.Context, []string) ([]string, error)
+	ListCollections(context.Context) ([]configuration.CollectionIdentity, error)
 }
 
 // ListingFilterMode selects namespace membership for one identity listing.
@@ -277,6 +279,21 @@ func (e *Engine) ListPrompts(ctx context.Context, filters ...ListingFilter) ([]d
 	return filtered, nil
 }
 
+func (e *Engine) ListNamespaces(ctx context.Context, kinds []string) ([]string, error) {
+	for _, kind := range kinds {
+		switch kind {
+		case "prompt", "profile", "backend":
+		default:
+			return nil, fmt.Errorf("%w: unknown resource kind %q", usecase.ErrInvalidRequest, kind)
+		}
+	}
+	return e.listing.ListNamespaces(ctx, kinds)
+}
+
+func (e *Engine) ListCollections(ctx context.Context) ([]configuration.CollectionIdentity, error) {
+	return e.listing.ListCollections(ctx)
+}
+
 func filterIdentityList(
 	ctx context.Context,
 	filters []ListingFilter,