expirable

Documentation

Index

• type EvictCallback
• type LRU
  • func NewLRU[K comparable, V any](size int, onEvict EvictCallback[K, V], ttl time.Duration) *LRU[K, V]
  • func (c *LRU[K, V]) Add(key K, value V) (evicted bool)
  • func (c *LRU[K, V]) Cap() int
  • func (c *LRU[K, V]) Contains(key K) (ok bool)
  • func (c *LRU[K, V]) Get(key K) (value V, ok bool)
  • func (c *LRU[K, V]) GetOldest() (key K, value V, ok bool)
  • func (c *LRU[K, V]) Keys() []K
  • func (c *LRU[K, V]) Len() int
  • func (c *LRU[K, V]) Peek(key K) (value V, ok bool)
  • func (c *LRU[K, V]) Purge()
  • func (c *LRU[K, V]) Remove(key K) bool
  • func (c *LRU[K, V]) RemoveOldest() (key K, value V, ok bool)
  • func (c *LRU[K, V]) Resize(size int) (evicted int)
  • func (c *LRU[K, V]) Values() []V

Types

type EvictCallback

type EvictCallback[K comparable, V any] func(key K, value V)

EvictCallback is used to get a callback when a cache entry is evicted

type LRU

type LRU[K comparable, V any] struct {
	// contains filtered or unexported fields
}

LRU implements a thread-safe LRU with expirable entries.

func NewLRU

func NewLRU[K comparable, V any](size int, onEvict EvictCallback[K, V], ttl time.Duration) *LRU[K, V]

NewLRU returns a new thread-safe cache with expirable entries.

Size parameter set to 0 makes cache of unlimited size, e.g. turns LRU mechanism off.

Providing 0 TTL turns expiring off.

Delete expired entries every 1/100th of ttl value. Goroutine which deletes expired entries runs indefinitely.

func (*LRU[K, V]) Add

func (c *LRU[K, V]) Add(key K, value V) (evicted bool)

Add adds a value to the cache. Returns true if an eviction occurred. Returns false if there was no eviction: the item was already in the cache, or the size was not exceeded.

func (*LRU[K, V]) Cap

func (c *LRU[K, V]) Cap() int

Cap returns the capacity of the cache

func (*LRU[K, V]) Contains

func (c *LRU[K, V]) Contains(key K) (ok bool)

Contains checks if a key is in the cache, without updating the recent-ness or deleting it for being stale.

func (*LRU[K, V]) Get

func (c *LRU[K, V]) Get(key K) (value V, ok bool)

Get looks up a key's value from the cache.

func (*LRU[K, V]) GetOldest

func (c *LRU[K, V]) GetOldest() (key K, value V, ok bool)

GetOldest returns the oldest entry

func (*LRU[K, V]) Keys

func (c *LRU[K, V]) Keys() []K

Keys returns a slice of the keys in the cache, from oldest to newest. Expired entries are filtered out.

func (*LRU[K, V]) Len

func (c *LRU[K, V]) Len() int

Len returns the number of items in the cache.

func (*LRU[K, V]) Peek

func (c *LRU[K, V]) Peek(key K) (value V, ok bool)

Peek returns the key value (or undefined if not found) without updating the "recently used"-ness of the key.

func (*LRU[K, V]) Purge

func (c *LRU[K, V]) Purge()

Purge clears the cache completely. onEvict is called for each evicted key.

func (*LRU[K, V]) Remove

func (c *LRU[K, V]) Remove(key K) bool

Remove removes the provided key from the cache, returning if the key was contained.

func (*LRU[K, V]) RemoveOldest

func (c *LRU[K, V]) RemoveOldest() (key K, value V, ok bool)

RemoveOldest removes the oldest item from the cache.

func (*LRU[K, V]) Resize

func (c *LRU[K, V]) Resize(size int) (evicted int)

Resize changes the cache size. Size of 0 means unlimited.

func (*LRU[K, V]) Values

func (c *LRU[K, V]) Values() []V

Values returns a slice of the values in the cache, from oldest to newest. Expired entries are filtered out.