示例#1
0
// Retrieve a cache item from the cache.
func (r *Redis) Get(key string, items ...kit.CacheItem) (kit.CacheItem, Error) {
	var item kit.CacheItem = &StrItem{}
	if items != nil {
		if len(items) != 1 {
			return nil, kit.AppError{
				Code:     "invalid_item",
				Message:  "You must specify one item only",
				Internal: true,
			}
		}
		item = items[0]
	}

	if key == "" {
		return nil, kit.AppError{Code: "empty_key"}
	}
	item.SetKey(key)
	key = r.key(key)

	conn := r.pool.Get()
	defer conn.Close()

	result, err := redis.Strings(conn.Do("MGET", key, r.tagKey(key)))
	if err != nil {
		return nil, redisErr(err)
	}

	// Retrieve the value.
	if result[0] == "" {
		return nil, nil
	}
	if err := item.FromString(result[0]); err != nil {
		return nil, kit.AppError{
			Code:    "cacheitem_fromstring_error",
			Message: err.Error(),
			Errors:  []error{err},
		}
	}

	// Parse and set tags.
	if result[1] != "" {
		item.SetTags(strings.Split(result[1], ";"))
	}

	// Now get the ttl.
	ttl, err := redis.Int(conn.Do("TTL", key))
	if err == nil && ttl > 0 {
		expires := time.Now().Add(time.Duration(ttl) * time.Second)
		item.SetExpiresAt(expires)
	} else if err != nil && err != redis.ErrNil {
		return nil, redisErr(err)
	}

	// Return nil if item is expired.
	if item.IsExpired() {
		return nil, nil
	}

	return item, nil
}