refactor: 自定义业务错误

backend/internal/repository/user_repo.go

@@ -2,56 +2,61 @@ package repository
 
 import (
 	"context"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+
 	"github.com/Wei-Shaw/sub2api/internal/model"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/pagination"
 
 	"gorm.io/gorm"
 )
 
-type UserRepository struct {
+type userRepository struct {
 	db *gorm.DB
 }
 
-func NewUserRepository(db *gorm.DB) *UserRepository {
-	return &UserRepository{db: db}
+func NewUserRepository(db *gorm.DB) service.UserRepository {
+	return &userRepository{db: db}
 }
 
-func (r *UserRepository) Create(ctx context.Context, user *model.User) error {
-	return r.db.WithContext(ctx).Create(user).Error
+func (r *userRepository) Create(ctx context.Context, user *model.User) error {
+	err := r.db.WithContext(ctx).Create(user).Error
+	return translatePersistenceError(err, nil, service.ErrEmailExists)
 }
 
-func (r *UserRepository) GetByID(ctx context.Context, id int64) (*model.User, error) {
+func (r *userRepository) GetByID(ctx context.Context, id int64) (*model.User, error) {
 	var user model.User
 	err := r.db.WithContext(ctx).First(&user, id).Error
 	if err != nil {
-		return nil, err
+		return nil, translatePersistenceError(err, service.ErrUserNotFound, nil)
 	}
 	return &user, nil
 }
 
-func (r *UserRepository) GetByEmail(ctx context.Context, email string) (*model.User, error) {
+func (r *userRepository) GetByEmail(ctx context.Context, email string) (*model.User, error) {
 	var user model.User
 	err := r.db.WithContext(ctx).Where("email = ?", email).First(&user).Error
 	if err != nil {
-		return nil, err
+		return nil, translatePersistenceError(err, service.ErrUserNotFound, nil)
 	}
 	return &user, nil
 }
 
-func (r *UserRepository) Update(ctx context.Context, user *model.User) error {
-	return r.db.WithContext(ctx).Save(user).Error
+func (r *userRepository) Update(ctx context.Context, user *model.User) error {
+	err := r.db.WithContext(ctx).Save(user).Error
+	return translatePersistenceError(err, nil, service.ErrEmailExists)
 }
 
-func (r *UserRepository) Delete(ctx context.Context, id int64) error {
+func (r *userRepository) Delete(ctx context.Context, id int64) error {
 	return r.db.WithContext(ctx).Delete(&model.User{}, id).Error
 }
 
-func (r *UserRepository) List(ctx context.Context, params pagination.PaginationParams) ([]model.User, *pagination.PaginationResult, error) {
+func (r *userRepository) List(ctx context.Context, params pagination.PaginationParams) ([]model.User, *pagination.PaginationResult, error) {
 	return r.ListWithFilters(ctx, params, "", "", "")
 }
 
 // ListWithFilters lists users with optional filtering by status, role, and search query
-func (r *UserRepository) ListWithFilters(ctx context.Context, params pagination.PaginationParams, status, role, search string) ([]model.User, *pagination.PaginationResult, error) {
+func (r *userRepository) ListWithFilters(ctx context.Context, params pagination.PaginationParams, status, role, search string) ([]model.User, *pagination.PaginationResult, error) {
 	var users []model.User
 	var total int64
 
@@ -120,13 +125,13 @@ func (r *UserRepository) ListWithFilters(ctx context.Context, params pagination.
 	}, nil
 }
 
-func (r *UserRepository) UpdateBalance(ctx context.Context, id int64, amount float64) error {
+func (r *userRepository) UpdateBalance(ctx context.Context, id int64, amount float64) error {
 	return r.db.WithContext(ctx).Model(&model.User{}).Where("id = ?", id).
 		Update("balance", gorm.Expr("balance + ?", amount)).Error
 }
 
 // DeductBalance 扣减用户余额，仅当余额充足时执行
-func (r *UserRepository) DeductBalance(ctx context.Context, id int64, amount float64) error {
+func (r *userRepository) DeductBalance(ctx context.Context, id int64, amount float64) error {
 	result := r.db.WithContext(ctx).Model(&model.User{}).
 		Where("id = ? AND balance >= ?", id, amount).
 		Update("balance", gorm.Expr("balance - ?", amount))
@@ -134,17 +139,17 @@ func (r *UserRepository) DeductBalance(ctx context.Context, id int64, amount flo
 		return result.Error
 	}
 	if result.RowsAffected == 0 {
-		return gorm.ErrRecordNotFound // 余额不足或用户不存在
+		return service.ErrInsufficientBalance
 	}
 	return nil
 }
 
-func (r *UserRepository) UpdateConcurrency(ctx context.Context, id int64, amount int) error {
+func (r *userRepository) UpdateConcurrency(ctx context.Context, id int64, amount int) error {
 	return r.db.WithContext(ctx).Model(&model.User{}).Where("id = ?", id).
 		Update("concurrency", gorm.Expr("concurrency + ?", amount)).Error
 }
 
-func (r *UserRepository) ExistsByEmail(ctx context.Context, email string) (bool, error) {
+func (r *userRepository) ExistsByEmail(ctx context.Context, email string) (bool, error) {
 	var count int64
 	err := r.db.WithContext(ctx).Model(&model.User{}).Where("email = ?", email).Count(&count).Error
 	return count > 0, err
@@ -152,7 +157,7 @@ func (r *UserRepository) ExistsByEmail(ctx context.Context, email string) (bool,
 
 // RemoveGroupFromAllowedGroups 从所有用户的 allowed_groups 数组中移除指定的分组ID
 // 使用 PostgreSQL 的 array_remove 函数
-func (r *UserRepository) RemoveGroupFromAllowedGroups(ctx context.Context, groupID int64) (int64, error) {
+func (r *userRepository) RemoveGroupFromAllowedGroups(ctx context.Context, groupID int64) (int64, error) {
 	result := r.db.WithContext(ctx).Model(&model.User{}).
 		Where("? = ANY(allowed_groups)", groupID).
 		Update("allowed_groups", gorm.Expr("array_remove(allowed_groups, ?)", groupID))
@@ -160,14 +165,14 @@ func (r *UserRepository) RemoveGroupFromAllowedGroups(ctx context.Context, group
 }
 
 // GetFirstAdmin 获取第一个管理员用户（用于 Admin API Key 认证）
-func (r *UserRepository) GetFirstAdmin(ctx context.Context) (*model.User, error) {
+func (r *userRepository) GetFirstAdmin(ctx context.Context) (*model.User, error) {
 	var user model.User
 	err := r.db.WithContext(ctx).
 		Where("role = ? AND status = ?", model.RoleAdmin, model.StatusActive).
 		Order("id ASC").
 		First(&user).Error
 	if err != nil {
-		return nil, err
+		return nil, translatePersistenceError(err, service.ErrUserNotFound, nil)
 	}
 	return &user, nil
 }