feat(dao): add dao

storage/dao/dao.go

@@ -18,6 +18,7 @@ func NewDao(lru lru.CacheInterface) *Dao {
 	}
 }
 
+// stringx 相关的方法
 func (d *Dao) Set(key *proto.BaseKey, strVal string) (string, error) {
 	value, ok := d.lru.Get(key)
 	if ok {
@@ -133,3 +134,63 @@ func (d *Dao) GetBit(key *proto.BaseKey, offer int32) (bool, error) {
 	}
 	return strVal.Getbit(offer)
 }
+
+func (d *Dao) Getrange(key *proto.BaseKey, start, end int32) (string, error) {
+	value, lruOk := d.lru.Get(key)
+	if !lruOk {
+		return "", errorx.NotKeyErr(key.Key)
+	}
+	strVal, ok := value.(structure.StringXInterface)
+	if !ok {
+		return "", errorx.DaoTypeErr("stringx")
+	}
+
+	return strVal.Getrange(start, end)
+}
+
+func (d *Dao) Getset(key *proto.BaseKey, value string) (string, error) {
+	val, ok := d.lru.Get(key)
+	if !ok {
+		return "", errorx.NotKeyErr(key.Key)
+	}
+
+	strVal, ok := val.(structure.StringXInterface)
+	if !ok {
+		return "", errorx.DaoTypeErr("stringx")
+	}
+
+	oldValue := strVal.Get()
+
+	_, updateLength := strVal.Set(value)
+	d.lru.UpdateLruSize(updateLength)
+	return oldValue, nil
+}
+
+func (d *Dao) Strlen(key *proto.BaseKey) (int32, error) {
+	val, ok := d.lru.Get(key)
+	if !ok {
+		return 0, errorx.NotKeyErr(key.Key)
+	}
+
+	strVal, ok := val.(structure.StringXInterface)
+	if !ok {
+		return 0, errorx.DaoTypeErr("stringx")
+	}
+
+	return int32(strVal.GetLength()), nil
+}
+
+func (d *Dao) Setnx(key *proto.BaseKey, val string) error {
+	_, ok := d.lru.Get(key)
+	if ok {
+		return errorx.New("the key already exists")
+	}
+
+	strValue := stringx.NewStringSingle()
+	strValue.Set(val)
+	err := d.lru.Add(key, strValue)
+	if err != nil {
+		return err
+	}
+	return nil
+}