func UpdateArticle(article *entities.Article) error {

	var err error
	db := db.NewDB()
	db.Begin()

	sql := "update article set title = ? ,tags=?,categories=?, content=?, updated_at=now() where user_id = ? and  id = ? "

	_, err = db.Raw(sql, []interface{}{article.Title, article.Tags, article.Categories, article.Content, article.UserId, article.Id}).Exec()

	if nil == err {
		var categories []entities.Category
		if len(article.Categories) > 0 {
			categoryNames := strings.Split(article.Categories, ",")
			categories = entities.NewCategories(article.UserId, categoryNames)
		}
		BatchSaveOrUpdateCategory(db, categories)
	}

	if nil == err {
		db.Commit()
	} else {
		db.Rollback()
	}

	return err
}
func SaveArticle(article *entities.Article) error {

	var err error
	db := db.NewDB()
	db.Begin()

	bBuffer := bytes.NewBufferString("insert into article (user_id,title, tags,categories, content, created_at) ")
	bBuffer.WriteString("values(?,?,?,?,?,now())")

	_, err = db.Raw(bBuffer.String(), []interface{}{article.UserId, article.Title, article.Tags, article.Categories, article.Content}).Exec()

	if nil == err {
		var categories []entities.Category
		if len(article.Categories) > 0 {
			categoryNames := strings.Split(article.Categories, ",")
			categories = entities.NewCategories(article.UserId, categoryNames)
		}
		BatchSaveOrUpdateCategory(db, categories)
	}

	if nil == err {
		db.Commit()
	} else {
		db.Rollback()
	}

	return err
}
func TestSaveCategories(t *testing.T) {
	categories := entities.NewCategories(2, []string{"go1", "go2"})
	services.BatchSaveOrUpdateCategory(db.NewDB(), categories)
}