test: Add tests for DeleteUser mutation and refactor errors

This commit introduces a new test suite for the `DeleteUser` GraphQL mutation in `internal/adapters/graphql/user_mutations_test.go`. The tests cover successful deletion by an admin and by the user themselves, as well as failure cases for invalid permissions, non-existent users, and invalid input.

During the implementation of these tests, an inconsistency in error handling was discovered. The `internal/data/sql` repositories were using a mix of local and domain-level errors. This has been refactored to consistently use the centralized errors defined in the `internal/domain` package. This change improves the robustness and predictability of the data layer.

The following files were modified to standardize error handling:
- internal/data/sql/base_repository.go
- internal/data/sql/book_repository.go
- internal/data/sql/category_repository.go
- internal/data/sql/copyright_repository.go
- internal/data/sql/country_repository.go
- internal/data/sql/edition_repository.go
- internal/data/sql/email_verification_repository.go
- internal/data/sql/password_reset_repository.go
- internal/data/sql/source_repository.go
- internal/data/sql/tag_repository.go
- internal/data/sql/user_profile_repository.go
- internal/data/sql/user_repository.go
- internal/data/sql/user_session_repository.go
- internal/data/sql/work_repository.go
- internal/data/sql/base_repository_test.go
- internal/data/sql/copyright_repository_test.go

internal/adapters/graphql/user_mutations_test.go

@@ -0,0 +1,155 @@
+package graphql_test
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os"
+	"testing"
+	"tercul/internal/adapters/graphql"
+	"tercul/internal/app/auth"
+	"tercul/internal/domain"
+	platform_auth "tercul/internal/platform/auth"
+	"tercul/internal/testutil"
+
+	"github.com/stretchr/testify/suite"
+)
+
+type UserMutationTestSuite struct {
+	testutil.IntegrationTestSuite
+	resolver graphql.MutationResolver
+}
+
+func TestUserMutations(t *testing.T) {
+	suite.Run(t, new(UserMutationTestSuite))
+}
+
+func (s *UserMutationTestSuite) SetupSuite() {
+	s.IntegrationTestSuite.SetupSuite(&testutil.TestConfig{
+		DBPath: "user_mutations_test.db",
+	})
+}
+
+func (s *UserMutationTestSuite) TearDownSuite() {
+	s.IntegrationTestSuite.TearDownSuite()
+	os.Remove("user_mutations_test.db")
+}
+
+func (s *UserMutationTestSuite) SetupTest() {
+	s.IntegrationTestSuite.SetupTest()
+	s.resolver = (&graphql.Resolver{App: s.App}).Mutation()
+}
+
+func (s *UserMutationTestSuite) TestDeleteUser() {
+	// Helper to create a user for tests
+	createUser := func(username, email, password string, role domain.UserRole) *domain.User {
+		resp, err := s.App.Auth.Commands.Register(context.Background(), auth.RegisterInput{
+			Username: username,
+			Email:    email,
+			Password: password,
+		})
+		s.Require().NoError(err)
+
+		user, err := s.App.User.Queries.User(context.Background(), resp.User.ID)
+		s.Require().NoError(err)
+
+		if role != user.Role {
+			user.Role = role
+			err = s.DB.Save(user).Error
+			s.Require().NoError(err)
+		}
+		return user
+	}
+
+	// Helper to create a context with JWT claims
+	contextWithClaims := func(user *domain.User) context.Context {
+		return testutil.ContextWithClaims(context.Background(), &platform_auth.Claims{
+			UserID: user.ID,
+			Role:   string(user.Role),
+		})
+	}
+
+	s.Run("Success as admin", func() {
+		// Arrange
+		adminUser := createUser("admin_deleter", "admin_deleter@test.com", "password123", domain.UserRoleAdmin)
+		userToDelete := createUser("user_to_delete", "user_to_delete@test.com", "password123", domain.UserRoleReader)
+		ctx := contextWithClaims(adminUser)
+		userIDToDeleteStr := fmt.Sprintf("%d", userToDelete.ID)
+
+		// Act
+		deleted, err := s.resolver.DeleteUser(ctx, userIDToDeleteStr)
+
+		// Assert
+		s.Require().NoError(err)
+		s.True(deleted)
+
+		// Verify user is deleted from DB
+		_, err = s.App.User.Queries.User(context.Background(), userToDelete.ID)
+		s.Error(err)
+		s.True(errors.Is(err, domain.ErrEntityNotFound), "Expected user to be not found after deletion")
+	})
+
+	s.Run("Success as self", func() {
+		// Arrange
+		userToDelete := createUser("user_to_delete_self", "user_to_delete_self@test.com", "password123", domain.UserRoleReader)
+		ctx := contextWithClaims(userToDelete)
+		userIDToDeleteStr := fmt.Sprintf("%d", userToDelete.ID)
+
+		// Act
+		deleted, err := s.resolver.DeleteUser(ctx, userIDToDeleteStr)
+
+		// Assert
+		s.Require().NoError(err)
+		s.True(deleted)
+
+		// Verify user is deleted from DB
+		_, err = s.App.User.Queries.User(context.Background(), userToDelete.ID)
+		s.Error(err)
+		s.True(errors.Is(err, domain.ErrEntityNotFound), "Expected user to be not found after deletion")
+	})
+
+	s.Run("Forbidden as other user", func() {
+		// Arrange
+		otherUser := createUser("other_user_deleter", "other_user_deleter@test.com", "password123", domain.UserRoleReader)
+		userToDelete := createUser("user_to_be_kept", "user_to_be_kept@test.com", "password123", domain.UserRoleReader)
+		ctx := contextWithClaims(otherUser)
+		userIDToDeleteStr := fmt.Sprintf("%d", userToDelete.ID)
+
+		// Act
+		deleted, err := s.resolver.DeleteUser(ctx, userIDToDeleteStr)
+
+		// Assert
+		s.Require().Error(err)
+		s.False(deleted)
+		s.True(errors.Is(err, domain.ErrForbidden))
+	})
+
+	s.Run("Invalid user ID", func() {
+		// Arrange
+		adminUser := createUser("admin_deleter_2", "admin_deleter_2@test.com", "password123", domain.UserRoleAdmin)
+		ctx := contextWithClaims(adminUser)
+
+		// Act
+		deleted, err := s.resolver.DeleteUser(ctx, "invalid-id")
+
+		// Assert
+		s.Require().Error(err)
+		s.False(deleted)
+		s.True(errors.Is(err, domain.ErrValidation))
+	})
+
+	s.Run("User not found", func() {
+		// Arrange
+		adminUser := createUser("admin_deleter_3", "admin_deleter_3@test.com", "password123", domain.UserRoleAdmin)
+		ctx := contextWithClaims(adminUser)
+		nonExistentID := "999999"
+
+		// Act
+		deleted, err := s.resolver.DeleteUser(ctx, nonExistentID)
+
+		// Assert
+		s.Require().Error(err)
+		s.False(deleted)
+		s.True(errors.Is(err, domain.ErrEntityNotFound), "Expected ErrEntityNotFound for non-existent user")
+	})
+}

internal/data/sql/base_repository.go

@@ -14,15 +14,7 @@ import (
 	"gorm.io/gorm"
 )
 
-// Common repository errors
+// Common repository errors are defined in the domain package.
-var (
-	ErrEntityNotFound    = errors.New("entity not found")
-	ErrInvalidID         = errors.New("invalid ID: cannot be zero")
-	ErrInvalidInput      = errors.New("invalid input parameters")
-	ErrDatabaseOperation = errors.New("database operation failed")
-	ErrContextRequired   = errors.New("context is required")
-	ErrTransactionFailed = errors.New("transaction failed")
-)
 
 // BaseRepositoryImpl provides a default implementation of BaseRepository using GORM
 type BaseRepositoryImpl[T any] struct {
@@ -43,7 +35,7 @@ func NewBaseRepositoryImpl[T any](db *gorm.DB, cfg *config.Config) *BaseReposito
 // validateContext ensures context is not nil
 func (r *BaseRepositoryImpl[T]) validateContext(ctx context.Context) error {
 	if ctx == nil {
-		return ErrContextRequired
+		return domain.ErrContextRequired
 	}
 	return nil
 }
@@ -51,7 +43,7 @@ func (r *BaseRepositoryImpl[T]) validateContext(ctx context.Context) error {
 // validateID ensures ID is valid
 func (r *BaseRepositoryImpl[T]) validateID(id uint) error {
 	if id == 0 {
-		return ErrInvalidID
+		return domain.ErrInvalidID
 	}
 	return nil
 }
@@ -59,7 +51,7 @@ func (r *BaseRepositoryImpl[T]) validateID(id uint) error {
 // validateEntity ensures entity is not nil
 func (r *BaseRepositoryImpl[T]) validateEntity(entity *T) error {
 	if entity == nil {
-		return ErrInvalidInput
+		return domain.ErrInvalidInput
 	}
 	return nil
 }
@@ -133,7 +125,7 @@ func (r *BaseRepositoryImpl[T]) Create(ctx context.Context, entity *T) error {
 
 	if err != nil {
 		log.Error(err, "Failed to create entity")
-		return fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	log.Debug(fmt.Sprintf("Entity created successfully in %s", duration))
@@ -151,7 +143,7 @@ func (r *BaseRepositoryImpl[T]) CreateInTx(ctx context.Context, tx *gorm.DB, ent
 		return err
 	}
 	if tx == nil {
-		return ErrTransactionFailed
+		return domain.ErrTransactionFailed
 	}
 
 	start := time.Now()
@@ -160,7 +152,7 @@ func (r *BaseRepositoryImpl[T]) CreateInTx(ctx context.Context, tx *gorm.DB, ent
 
 	if err != nil {
 		log.Error(err, "Failed to create entity in transaction")
-		return fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	log.Debug(fmt.Sprintf("Entity created successfully in transaction in %s", duration))
@@ -186,10 +178,10 @@ func (r *BaseRepositoryImpl[T]) GetByID(ctx context.Context, id uint) (*T, error
 	if err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			log.Debug(fmt.Sprintf("Entity with id %d not found in %s", id, duration))
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		log.Error(err, fmt.Sprintf("Failed to get entity by ID %d", id))
-		return nil, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return nil, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	log.Debug(fmt.Sprintf("Entity with id %d retrieved successfully in %s", id, duration))
@@ -216,10 +208,10 @@ func (r *BaseRepositoryImpl[T]) GetByIDWithOptions(ctx context.Context, id uint,
 	if err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			log.Debug(fmt.Sprintf("Entity with id %d not found with options in %s", id, duration))
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		log.Error(err, fmt.Sprintf("Failed to get entity by ID %d with options", id))
-		return nil, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return nil, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	log.Debug(fmt.Sprintf("Entity with id %d retrieved successfully with options in %s", id, duration))
@@ -243,7 +235,7 @@ func (r *BaseRepositoryImpl[T]) Update(ctx context.Context, entity *T) error {
 
 	if err != nil {
 		log.Error(err, "Failed to update entity")
-		return fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	log.Debug(fmt.Sprintf("Entity updated successfully in %s", duration))
@@ -261,7 +253,7 @@ func (r *BaseRepositoryImpl[T]) UpdateInTx(ctx context.Context, tx *gorm.DB, ent
 		return err
 	}
 	if tx == nil {
-		return ErrTransactionFailed
+		return domain.ErrTransactionFailed
 	}
 
 	start := time.Now()
@@ -270,7 +262,7 @@ func (r *BaseRepositoryImpl[T]) UpdateInTx(ctx context.Context, tx *gorm.DB, ent
 
 	if err != nil {
 		log.Error(err, "Failed to update entity in transaction")
-		return fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	log.Debug(fmt.Sprintf("Entity updated successfully in transaction in %s", duration))
@@ -295,12 +287,12 @@ func (r *BaseRepositoryImpl[T]) Delete(ctx context.Context, id uint) error {
 
 	if result.Error != nil {
 		log.Error(result.Error, fmt.Sprintf("Failed to delete entity with id %d", id))
-		return fmt.Errorf("%w: %v", ErrDatabaseOperation, result.Error)
+		return fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, result.Error)
 	}
 
 	if result.RowsAffected == 0 {
 		log.Debug(fmt.Sprintf("No entity with id %d found to delete in %s", id, duration))
-		return ErrEntityNotFound
+		return domain.ErrEntityNotFound
 	}
 
 	log.Debug(fmt.Sprintf("Entity with id %d deleted successfully in %s", id, duration))
@@ -318,7 +310,7 @@ func (r *BaseRepositoryImpl[T]) DeleteInTx(ctx context.Context, tx *gorm.DB, id
 		return err
 	}
 	if tx == nil {
-		return ErrTransactionFailed
+		return domain.ErrTransactionFailed
 	}
 
 	start := time.Now()
@@ -328,12 +320,12 @@ func (r *BaseRepositoryImpl[T]) DeleteInTx(ctx context.Context, tx *gorm.DB, id
 
 	if result.Error != nil {
 		log.Error(result.Error, fmt.Sprintf("Failed to delete entity with id %d in transaction", id))
-		return fmt.Errorf("%w: %v", ErrDatabaseOperation, result.Error)
+		return fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, result.Error)
 	}
 
 	if result.RowsAffected == 0 {
 		log.Debug(fmt.Sprintf("No entity with id %d found to delete in transaction in %s", id, duration))
-		return ErrEntityNotFound
+		return domain.ErrEntityNotFound
 	}
 
 	log.Debug(fmt.Sprintf("Entity with id %d deleted successfully in transaction in %s", id, duration))
@@ -360,7 +352,7 @@ func (r *BaseRepositoryImpl[T]) List(ctx context.Context, page, pageSize int) (*
 	// Get total count
 	if err := r.db.WithContext(ctx).Model(new(T)).Count(&totalCount).Error; err != nil {
 		log.Error(err, "Failed to count entities")
-		return nil, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return nil, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	// Calculate offset
@@ -369,7 +361,7 @@ func (r *BaseRepositoryImpl[T]) List(ctx context.Context, page, pageSize int) (*
 	// Get paginated data
 	if err := r.db.WithContext(ctx).Offset(offset).Limit(pageSize).Find(&entities).Error; err != nil {
 		log.Error(err, "Failed to get paginated entities")
-		return nil, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return nil, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	duration := time.Since(start)
@@ -410,7 +402,7 @@ func (r *BaseRepositoryImpl[T]) ListWithOptions(ctx context.Context, options *do
 
 	if err := query.Find(&entities).Error; err != nil {
 		log.Error(err, "Failed to get entities with options")
-		return nil, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return nil, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	duration := time.Since(start)
@@ -431,7 +423,7 @@ func (r *BaseRepositoryImpl[T]) ListAll(ctx context.Context) ([]T, error) {
 	var entities []T
 	if err := r.db.WithContext(ctx).Find(&entities).Error; err != nil {
 		log.Error(err, "Failed to get all entities")
-		return nil, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return nil, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	duration := time.Since(start)
@@ -452,7 +444,7 @@ func (r *BaseRepositoryImpl[T]) Count(ctx context.Context) (int64, error) {
 	var count int64
 	if err := r.db.WithContext(ctx).Model(new(T)).Count(&count).Error; err != nil {
 		log.Error(err, "Failed to count entities")
-		return 0, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return 0, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	duration := time.Since(start)
@@ -475,7 +467,7 @@ func (r *BaseRepositoryImpl[T]) CountWithOptions(ctx context.Context, options *d
 
 	if err := query.Model(new(T)).Count(&count).Error; err != nil {
 		log.Error(err, "Failed to count entities with options")
-		return 0, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return 0, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	duration := time.Since(start)
@@ -506,10 +498,10 @@ func (r *BaseRepositoryImpl[T]) FindWithPreload(ctx context.Context, preloads []
 	if err := query.First(&entity, id).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			log.Debug(fmt.Sprintf("Entity with id %d not found with preloads in %s", id, time.Since(start)))
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		log.Error(err, fmt.Sprintf("Failed to get entity with id %d with preloads", id))
-		return nil, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return nil, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	duration := time.Since(start)
@@ -541,7 +533,7 @@ func (r *BaseRepositoryImpl[T]) GetAllForSync(ctx context.Context, batchSize, of
 	var entities []T
 	if err := r.db.WithContext(ctx).Offset(offset).Limit(batchSize).Find(&entities).Error; err != nil {
 		log.Error(err, "Failed to get entities for sync")
-		return nil, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return nil, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	duration := time.Since(start)
@@ -565,7 +557,7 @@ func (r *BaseRepositoryImpl[T]) Exists(ctx context.Context, id uint) (bool, erro
 	var count int64
 	if err := r.db.WithContext(ctx).Model(new(T)).Where("id = ?", id).Count(&count).Error; err != nil {
 		log.Error(err, fmt.Sprintf("Failed to check entity existence for id %d", id))
-		return false, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return false, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 
 	duration := time.Since(start)
@@ -587,7 +579,7 @@ func (r *BaseRepositoryImpl[T]) BeginTx(ctx context.Context) (*gorm.DB, error) {
 	tx := r.db.WithContext(ctx).Begin()
 	if tx.Error != nil {
 		log.Error(tx.Error, "Failed to begin transaction")
-		return nil, fmt.Errorf("%w: %v", ErrTransactionFailed, tx.Error)
+		return nil, fmt.Errorf("%w: %v", domain.ErrTransactionFailed, tx.Error)
 	}
 
 	log.Debug("Transaction started successfully")
@@ -625,9 +617,9 @@ func (r *BaseRepositoryImpl[T]) WithTx(ctx context.Context, fn func(tx *gorm.DB)
 
 	if err := tx.Commit().Error; err != nil {
 		log.Error(err, "Failed to commit transaction")
-		return fmt.Errorf("%w: %v", ErrTransactionFailed, err)
+		return fmt.Errorf("%w: %v", domain.ErrTransactionFailed, err)
 	}
 
 	log.Debug("Transaction committed successfully")
 	return nil
-}
+}

internal/data/sql/base_repository_test.go

@@ -76,13 +76,13 @@ func (s *BaseRepositoryTestSuite) TestCreate() {
 
 	s.Run("should return error for nil entity", func() {
 		err := s.repo.Create(context.Background(), nil)
-		s.ErrorIs(err, sql.ErrInvalidInput)
+		s.ErrorIs(err, domain.ErrInvalidInput)
 	})
 
 	s.Run("should return error for nil context", func() {
 		//nolint:staticcheck // Testing behavior with nil context is intentional here.
 		err := s.repo.Create(nil, &testutil.TestEntity{Name: "Test Context"})
-		s.ErrorIs(err, sql.ErrContextRequired)
+		s.ErrorIs(err, domain.ErrContextRequired)
 	})
 }
 
@@ -103,12 +103,12 @@ func (s *BaseRepositoryTestSuite) TestGetByID() {
 
 	s.Run("should return ErrEntityNotFound for non-existent ID", func() {
 		_, err := s.repo.GetByID(context.Background(), 99999)
-		s.ErrorIs(err, sql.ErrEntityNotFound)
+		s.ErrorIs(err, domain.ErrEntityNotFound)
 	})
 
 	s.Run("should return ErrInvalidID for zero ID", func() {
 		_, err := s.repo.GetByID(context.Background(), 0)
-		s.ErrorIs(err, sql.ErrInvalidID)
+		s.ErrorIs(err, domain.ErrInvalidID)
 	})
 }
 
@@ -140,12 +140,12 @@ func (s *BaseRepositoryTestSuite) TestDelete() {
 		// Assert
 		s.Require().NoError(err)
 		_, getErr := s.repo.GetByID(context.Background(), created.ID)
-		s.ErrorIs(getErr, sql.ErrEntityNotFound)
+		s.ErrorIs(getErr, domain.ErrEntityNotFound)
 	})
 
 	s.Run("should return ErrEntityNotFound when deleting non-existent entity", func() {
 		err := s.repo.Delete(context.Background(), 99999)
-		s.ErrorIs(err, sql.ErrEntityNotFound)
+		s.ErrorIs(err, domain.ErrEntityNotFound)
 	})
 }
 
@@ -261,6 +261,6 @@ func (s *BaseRepositoryTestSuite) TestWithTx() {
 		s.ErrorIs(err, simulatedErr)
 
 		_, getErr := s.repo.GetByID(context.Background(), createdID)
-		s.ErrorIs(getErr, sql.ErrEntityNotFound, "Entity should not exist after rollback")
+		s.ErrorIs(getErr, domain.ErrEntityNotFound, "Entity should not exist after rollback")
 	})
 }

internal/data/sql/book_repository.go

@@ -70,7 +70,7 @@ func (r *bookRepository) FindByISBN(ctx context.Context, isbn string) (*domain.B
 	var book domain.Book
 	if err := r.db.WithContext(ctx).Where("isbn = ?", isbn).First(&book).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/category_repository.go

@@ -33,7 +33,7 @@ func (r *categoryRepository) FindByName(ctx context.Context, name string) (*doma
 	var category domain.Category
 	if err := r.db.WithContext(ctx).Where("name = ?", name).First(&category).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/copyright_repository.go

@@ -50,7 +50,7 @@ func (r *copyrightRepository) GetTranslationByLanguage(ctx context.Context, copy
 	err := r.db.WithContext(ctx).Where("copyright_id = ? AND language_code = ?", copyrightID, languageCode).First(&translation).Error
 	if err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/copyright_repository_test.go

@@ -127,7 +127,7 @@ func (s *CopyrightRepositoryTestSuite) TestGetTranslationByLanguage() {
 
 		_, err := s.repo.GetTranslationByLanguage(context.Background(), copyrightID, languageCode)
 		s.Require().Error(err)
-		s.Require().Equal(sql.ErrEntityNotFound, err)
+		s.Require().ErrorIs(err, domain.ErrEntityNotFound)
 	})
 }
 

internal/data/sql/country_repository.go

@@ -27,7 +27,7 @@ func (r *countryRepository) GetByCode(ctx context.Context, code string) (*domain
 	var country domain.Country
 	if err := r.db.WithContext(ctx).Where("code = ?", code).First(&country).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/edition_repository.go

@@ -44,7 +44,7 @@ func (r *editionRepository) FindByISBN(ctx context.Context, isbn string) (*domai
 	var edition domain.Edition
 	if err := r.db.WithContext(ctx).Where("isbn = ?", isbn).First(&edition).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/email_verification_repository.go

@@ -34,7 +34,7 @@ func (r *emailVerificationRepository) GetByToken(ctx context.Context, token stri
 	var verification domain.EmailVerification
 	if err := r.db.WithContext(ctx).Where("token = ? AND used = ? AND expires_at > ?", token, false, time.Now()).First(&verification).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/password_reset_repository.go

@@ -34,7 +34,7 @@ func (r *passwordResetRepository) GetByToken(ctx context.Context, token string)
 	var reset domain.PasswordReset
 	if err := r.db.WithContext(ctx).Where("token = ? AND used = ? AND expires_at > ?", token, false, time.Now()).First(&reset).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/source_repository.go

@@ -46,7 +46,7 @@ func (r *sourceRepository) FindByURL(ctx context.Context, url string) (*domain.S
 	var source domain.Source
 	if err := r.db.WithContext(ctx).Where("url = ?", url).First(&source).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/tag_repository.go

@@ -33,7 +33,7 @@ func (r *tagRepository) FindByName(ctx context.Context, name string) (*domain.Ta
 	var tag domain.Tag
 	if err := r.db.WithContext(ctx).Where("name = ?", name).First(&tag).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/user_profile_repository.go

@@ -33,7 +33,7 @@ func (r *userProfileRepository) GetByUserID(ctx context.Context, userID uint) (*
 	var profile domain.UserProfile
 	if err := r.db.WithContext(ctx).Where("user_id = ?", userID).First(&profile).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/user_repository.go

@@ -33,7 +33,7 @@ func (r *userRepository) FindByUsername(ctx context.Context, username string) (*
 	var user domain.User
 	if err := r.db.WithContext(ctx).Where("username = ?", username).First(&user).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}
@@ -47,7 +47,7 @@ func (r *userRepository) FindByEmail(ctx context.Context, email string) (*domain
 	var user domain.User
 	if err := r.db.WithContext(ctx).Where("email = ?", email).First(&user).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}
@@ -63,4 +63,4 @@ func (r *userRepository) ListByRole(ctx context.Context, role domain.UserRole) (
 		return nil, err
 	}
 	return users, nil
-}
+}

internal/data/sql/user_session_repository.go

@@ -34,7 +34,7 @@ func (r *userSessionRepository) GetByToken(ctx context.Context, token string) (*
 	var session domain.UserSession
 	if err := r.db.WithContext(ctx).Where("token = ?", token).First(&session).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
 		return nil, err
 	}

internal/data/sql/work_repository.go

@@ -185,9 +185,9 @@ func (r *workRepository) GetWithAssociationsInTx(ctx context.Context, tx *gorm.D
 	}
 	if err := query.First(&entity, id).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, ErrEntityNotFound
+			return nil, domain.ErrEntityNotFound
 		}
-		return nil, fmt.Errorf("%w: %v", ErrDatabaseOperation, err)
+		return nil, fmt.Errorf("%w: %v", domain.ErrDatabaseOperation, err)
 	}
 	return &entity, nil
 }