go 继承式反射

// 层级递增解析tag
func GetReflectTag(reflectType reflect.Type, buf *bytes.Buffer) {

	if reflectType.Kind() != reflect.Struct {
		return
	}
	for i := 0; i < reflectType.NumField(); i++ {
		tag := reflectType.Field(i).Tag.Get("json")
		if tag == "" {
			GetReflectTag(reflectType.Field(i).Type, buf)
			continue
		}
		buf.WriteString("`")
		buf.WriteString(tag)
		buf.WriteString("`,")
	}
}
// 根据model中表模型的json标签获取表字段
// 将select* 变为对应的字段名
func GetColSQL(model interface{}) (sql string) {
	var buf bytes.Buffer

	typ := reflect.TypeOf(model)
	for i := 0; i < typ.NumField(); i++ {
		tag := typ.Field(i).Tag.Get("json")
		if tag == "" {
			GetReflectTag(typ.Field(i).Type, &buf)

			//Logger().Println(reflectType.Field(i).Tag.Get("json"))
			//Logger().Println(reflectType.NumField())
			//Logger().Println(GetColSQL(reflectType))
			continue
		}
		// sql += "`" + tag + "`,"
		buf.WriteString("`")
		buf.WriteString(tag)
		buf.WriteString("`,")
	}
	sql = string(buf.Bytes()[:buf.Len()-1]) //去掉点,
	return sql
}

func TestExtends(t *testing.T)  {
	type UserDe struct {
		User
		Other string `json:"other"`
	}

	type UserDeX struct {
		a []string
		UserDe
		OtherX string `json:"other_x"`
	}

	type UserMore struct {
		UserDeX
		ShopName string `json:"shop_name"`
	}
	t.Log(GetColSQL(UserDeX{}))
	//t.Log(GetMoreTableColumnSQL(UserMore{}, []string{"user","shop"}[:]...))
}

// output 
=== RUN   TestExtends
--- PASS: TestExtends (0.00s)
    db_test.go:301: `id`,`name`,`createtime`,`other`,`other_x`
PASS