feat: add join group service

internal/group/group.repository.go

@@ -18,6 +18,7 @@ type Repository interface {
 	DeleteMemberFromGroupWithTX(ctx context.Context, tx *gorm.DB, userUUID, groupUUID uuid.UUID) error
 	CreateNewGroupWithTX(ctx context.Context, tx *gorm.DB, leaderId string) (*model.Group, error)
 	JoinGroupWithTX(ctx context.Context, tx *gorm.DB, userUUID, groupUUID uuid.UUID) error
+	DeleteGroup(ctx context.Context, tx *gorm.DB, groupUUID uuid.UUID) error
 }
 
 type repositoryImpl struct {
@@ -137,3 +138,15 @@ func (r *repositoryImpl) JoinGroupWithTX(ctx context.Context, tx *gorm.DB, userU
 
 	return nil
 }
+
+func (r *repositoryImpl) DeleteGroup(ctx context.Context, tx *gorm.DB, groupUUID uuid.UUID) error {
+	result := r.Db.Delete(&model.Group{}, "id = ?", groupUUID)
+	if result.Error != nil {
+		return result.Error
+	}
+	if result.RowsAffected == 0 {
+		return errors.New("not found group match with given id")
+	}
+
+	return nil
+}

internal/group/group.service.go

@@ -344,6 +344,10 @@ func (s *serviceImpl) Join(ctx context.Context, in *proto.JoinGroupRequest) (*pr
 		return nil, err
 	}
 
+	if in.UserId == existedGroup.LeaderID && len(existedGroup.Members) > 1 {
+		return nil, errors.New("requested user_id is leader of this group so you cannot leave")
+	}
+
 	err = s.repo.WithTransaction(func(tx *gorm.DB) error {
 		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 		defer cancel()
@@ -358,8 +362,11 @@ func (s *serviceImpl) Join(ctx context.Context, in *proto.JoinGroupRequest) (*pr
 			return err
 		}
 
-		if err := s.repo.DeleteMemberFromGroupWithTX(ctx, tx, userUUID, existedGroup.ID); err != nil {
-			return err
+		if in.UserId == existedGroup.LeaderID && len(existedGroup.Members) == 1 {
+			err := s.repo.DeleteGroup(ctx, tx, existedGroup.ID)
+			if err != nil {
+				return err
+			}
 		}
 
 		return nil