// Save a new item into the cache.
func (r *Redis) Set(item kit.CacheItem) Error {
key := item.GetKey()
if key == "" {
return kit.AppError{Code: "empty_key"}
}
key = r.key(key)
if item.IsExpired() {
return kit.AppError{Code: "item_expired"}
}
expireSeconds := 0
if expires := item.GetExpiresAt(); !expires.IsZero() {
seconds := expires.Sub(time.Now()).Seconds()
if seconds > 0 && seconds < 1 {
return kit.AppError{Code: "item_expired"}
}
expireSeconds = int(seconds)
}
conn := r.pool.Get()
defer conn.Close()
value, err := item.ToString()
if err != nil {
return kit.AppError{
Code: "cacheitem_tostring_error",
Message: err.Error(),
Errors: []error{err},
}
}
if value == "" {
return kit.AppError{Code: "empty_value"}
}
conn.Send("SET", key, value)
if expireSeconds > 0 {
conn.Send("EXPIRE", key, expireSeconds)
}
if tags := item.GetTags(); tags != nil {
tagKey := r.tagKey(key)
conn.Send("SET", tagKey, strings.Join(tags, ";"))
if expireSeconds > 0 {
conn.Send("EXPIRE", tagKey, expireSeconds)
}
}
if err := conn.Flush(); err != nil {
return redisErr(err)
}
return nil
}
// Retrieve a cache item from the cache.
func (fs *Fs) Get(key string, items ...kit.CacheItem) (kit.CacheItem, apperror.Error) {
var item kit.CacheItem = &StrItem{}
if items != nil {
if len(items) != 1 {
return nil, &apperror.Err{
Code: "invalid_item",
Message: "You must specify one item only",
}
}
item = items[0]
}
key = fs.key(key)
if key == "" {
return nil, apperror.New("empty_key")
}
exists, err := utils.FileExists(fs.keyPath(key))
if err != nil {
return nil, err
}
if !exists {
return nil, nil
}
metaContent, err := utils.ReadFile(fs.keyMetaPath(key))
if err != nil {
return nil, err
}
if err := json.Unmarshal(metaContent, &item); err != nil {
return nil, apperror.Wrap(err, "metadata_unmarshal_error")
}
// Reset ExpiresAt if it is zero, since json.Unmarshal produces
// a time.Time which is not exactly equal to the zero value.
if item.GetExpiresAt().IsZero() {
item.SetExpiresAt(time.Time{})
}
content, err := utils.ReadFile(fs.keyPath(key))
if err != nil {
return nil, err
}
if err := item.FromString(string(content)); err != nil {
return nil, apperror.Wrap(err, "cacheitem_fromstring_error")
}
// Return nil if item is expired.
if item.IsExpired() {
return nil, nil
}
return item, nil
}
// Save a new item into the cache.
func (fs *Fs) Set(item kit.CacheItem) apperror.Error {
key := fs.key(item.GetKey())
if key == "" {
return apperror.New("empty_key")
}
if item.IsExpired() {
return apperror.New("item_expired")
}
value, err := item.ToString()
if err != nil {
return apperror.Wrap(err, "cacheitem_tostring_error")
}
if value == "" {
return apperror.New("empty_value")
}
// Marshal metadata.
tmpVal := item.GetValue()
item.SetValue(nil)
js, err2 := json.Marshal(item)
if err2 != nil {
return apperror.Wrap(err2, "json_marshal_error")
}
item.SetValue(tmpVal)
if err := utils.WriteFile(fs.keyPath(key), []byte(value), false); err != nil {
return err
}
if err := utils.WriteFile(fs.keyMetaPath(key), js, false); err != nil {
return err
}
return nil
}
// 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
}
