Initial commit: Open sourcing all of the Maple Open Technologies code.

cloud/maplefile-backend/internal/usecase/collection/find_descendants.go

@@ -0,0 +1,54 @@
+// monorepo/cloud/backend/internal/maplefile/usecase/collection/find_descendants.go
+package collection
+
+import (
+	"context"
+
+	"go.uber.org/zap"
+
+	"github.com/gocql/gocql"
+	"codeberg.org/mapleopentech/monorepo/cloud/maplefile-backend/config"
+	dom_collection "codeberg.org/mapleopentech/monorepo/cloud/maplefile-backend/internal/domain/collection"
+	"codeberg.org/mapleopentech/monorepo/cloud/maplefile-backend/pkg/httperror"
+)
+
+type FindDescendantsUseCase interface {
+	Execute(ctx context.Context, collectionID gocql.UUID) ([]*dom_collection.Collection, error)
+}
+
+type findDescendantsUseCaseImpl struct {
+	config *config.Configuration
+	logger *zap.Logger
+	repo   dom_collection.CollectionRepository
+}
+
+func NewFindDescendantsUseCase(
+	config *config.Configuration,
+	logger *zap.Logger,
+	repo dom_collection.CollectionRepository,
+) FindDescendantsUseCase {
+	logger = logger.Named("FindDescendantsUseCase")
+	return &findDescendantsUseCaseImpl{config, logger, repo}
+}
+
+func (uc *findDescendantsUseCaseImpl) Execute(ctx context.Context, collectionID gocql.UUID) ([]*dom_collection.Collection, error) {
+	//
+	// STEP 1: Validation.
+	//
+
+	e := make(map[string]string)
+	if collectionID.String() == "" {
+		e["collection_id"] = "Collection ID is required"
+	}
+	if len(e) != 0 {
+		uc.logger.Warn("Failed validating find descendants",
+			zap.Any("error", e))
+		return nil, httperror.NewForBadRequest(&e)
+	}
+
+	//
+	// STEP 2: Find descendants.
+	//
+
+	return uc.repo.FindDescendants(ctx, collectionID)
+}