Documentation
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Index ¶
- Constants
- type Cache
- func (c Cache) Add(k string, x interface{}, d time.Duration) error
- func (c Cache) Delete(k string)
- func (c Cache) DeleteExpired()
- func (c Cache) Flush()
- func (c Cache) Get(k string) (interface{}, bool)
- func (c Cache) GetWithExpiration(k string) (interface{}, time.Time, bool)
- func (c Cache) Has(k string) bool
- func (c Cache) ItemCount() int
- func (c Cache) Items() map[string]Item
- func (c Cache) Load(r io.Reader) error
- func (c Cache) LoadFile(fname string) error
- func (c Cache) OnEvicted(f func(string, interface{}))
- func (c Cache) Pop(k string) (interface{}, bool)
- func (c Cache) Replace(k string, x interface{}, d time.Duration) error
- func (c Cache) Save(w io.Writer) (err error)
- func (c Cache) SaveFile(fname string) error
- func (c Cache) Set(k string, x interface{}, d time.Duration)
- func (c Cache) SetDefault(k string, x interface{})
- func (c Cache) Touch(k string, d time.Duration) bool
- type Item
- type ShardedCache
- func (sc ShardedCache) Add(k string, x interface{}, d time.Duration) error
- func (sc ShardedCache) Delete(k string)
- func (sc ShardedCache) DeleteExpired()
- func (sc ShardedCache) Flush()
- func (sc ShardedCache) Get(k string) (interface{}, bool)
- func (sc ShardedCache) GetOrStore(k string, v func() (interface{}, error), d time.Duration) (interface{}, error)
- func (sc ShardedCache) Has(k string) bool
- func (sc ShardedCache) Items() []map[string]Item
- func (sc ShardedCache) ItemsCount() (rv int)
- func (sc ShardedCache) Pop(k string) (rv interface{}, deleted bool)
- func (sc ShardedCache) Replace(k string, x interface{}, d time.Duration) error
- func (sc ShardedCache) Set(k string, x interface{}, d time.Duration)
- func (sc ShardedCache) Touch(k string, d time.Duration) bool
Constants ¶
const ( // For use with functions that take an expiration time. NoExpiration time.Duration = -1 // For use with functions that take an expiration time. Equivalent to // passing in the same expiration duration as was given to New() or // NewFrom() when the cache was created (e.g. 5 minutes.) DefaultExpiration time.Duration = 0 )
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Cache ¶
type Cache struct {
// contains filtered or unexported fields
}
func New ¶
Return a new cache with a given default expiration duration and cleanup interval. If the expiration duration is less than one (or NoExpiration), the items in the cache never expire (by default), and must be deleted manually. If the cleanup interval is less than one, expired items are not deleted from the cache before calling c.DeleteExpired().
func NewFrom ¶
Return a new cache with a given default expiration duration and cleanup interval. If the expiration duration is less than one (or NoExpiration), the items in the cache never expire (by default), and must be deleted manually. If the cleanup interval is less than one, expired items are not deleted from the cache before calling c.DeleteExpired().
NewFrom() also accepts an items map which will serve as the underlying map for the cache. This is useful for starting from a deserialized cache (serialized using e.g. gob.Encode() on c.Items()), or passing in e.g. make(map[string]Item, 500) to improve startup performance when the cache is expected to reach a certain minimum size.
Only the cache's methods synchronize access to this map, so it is not recommended to keep any references to the map around after creating a cache. If need be, the map can be accessed at a later point using c.Items() (subject to the same caveat.)
Note regarding serialization: When using e.g. gob, make sure to gob.Register() the individual types stored in the cache before encoding a map retrieved with c.Items(), and to register those same types before decoding a blob containing an items map.
func (Cache) Add ¶
Add an item to the cache only if an item doesn't already exist for the given key, or if the existing item has expired. Returns an error otherwise.
func (Cache) Delete ¶
func (c Cache) Delete(k string)
Delete an item from the cache. Does nothing if the key is not in the cache.
func (Cache) DeleteExpired ¶
func (c Cache) DeleteExpired()
Delete all expired items from the cache.
func (Cache) Get ¶
Get an item from the cache. Returns the item or nil, and a bool indicating whether the key was found.
func (Cache) GetWithExpiration ¶
GetWithExpiration returns an item and its expiration time from the cache. It returns the item or nil, the expiration time if one is set (if the item never expires a zero value for time.Time is returned), and a bool indicating whether the key was found.
func (Cache) ItemCount ¶
func (c Cache) ItemCount() int
Returns the number of items in the cache. This may include items that have expired, but have not yet been cleaned up.
func (Cache) Load ¶
Add (Gob-serialized) cache items from an io.Reader, excluding any items with keys that already exist (and haven't expired) in the current cache.
NOTE: This method is deprecated in favor of c.Items() and NewFrom() (see the documentation for NewFrom().)
func (Cache) LoadFile ¶
Load and add cache items from the given filename, excluding any items with keys that already exist in the current cache.
NOTE: This method is deprecated in favor of c.Items() and NewFrom() (see the documentation for NewFrom().)
func (Cache) OnEvicted ¶
func (c Cache) OnEvicted(f func(string, interface{}))
Sets an (optional) function that is called with the key and value when an item is evicted from the cache. (Including when it is deleted manually, but not when it is overwritten.) Set to nil to disable.
func (Cache) Replace ¶
Set a new value for the cache key only if it already exists, and the existing item hasn't expired. Returns an error otherwise.
func (Cache) Save ¶
Write the cache's items (using Gob) to an io.Writer.
NOTE: This method is deprecated in favor of c.Items() and NewFrom() (see the documentation for NewFrom().)
func (Cache) SaveFile ¶
Save the cache's items to the given filename, creating the file if it doesn't exist, and overwriting it if it does.
NOTE: This method is deprecated in favor of c.Items() and NewFrom() (see the documentation for NewFrom().)
func (Cache) Set ¶
Add an item to the cache, replacing any existing item. If the duration is 0 (DefaultExpiration), the cache's default expiration time is used. If it is -1 (NoExpiration), the item never expires.
func (Cache) SetDefault ¶
func (c Cache) SetDefault(k string, x interface{})
Add an item to the cache, replacing any existing item, using the default expiration.
type ShardedCache ¶
type ShardedCache struct {
// contains filtered or unexported fields
}
func NewSharded ¶
func NewSharded(defaultExpiration, cleanupInterval time.Duration, shards int) *ShardedCache
func (ShardedCache) DeleteExpired ¶
func (sc ShardedCache) DeleteExpired()
Remove all expired items from the cache.
func (ShardedCache) GetOrStore ¶
func (sc ShardedCache) GetOrStore( k string, v func() (interface{}, error), d time.Duration, ) (interface{}, error)
Get an item from the cache, or store the value.
func (ShardedCache) Items ¶
Returns the items in the cache. This may include items that have expired, but have not yet been cleaned up. If this is significant, the Expiration fields of the items should be checked. Note that explicit synchronization is needed to use a cache and its corresponding Items() return values at the same time, as the maps are shared.
func (ShardedCache) ItemsCount ¶
func (sc ShardedCache) ItemsCount() (rv int)
Returns the number of items in the cache. This may include items that have expired, but have not yet been cleaned up.
Source Files