package lru

import "gorm.io/gorm/internal/lru"

Index ¶

• type Entry
• func (e *Entry[K, V]) PrevEntry() *Entry[K, V]
• 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]) KeyValues() map[K]V
• 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
• type LruList
• func NewList[K comparable, V any]() *LruList[K, V]
• func (l *LruList[K, V]) Back() *Entry[K, V]
• func (l *LruList[K, V]) Init() *LruList[K, V]
• func (l *LruList[K, V]) Length() int
• func (l *LruList[K, V]) MoveToFront(e *Entry[K, V])
• func (l *LruList[K, V]) PushFront(k K, v V) *Entry[K, V]
• func (l *LruList[K, V]) PushFrontExpirable(k K, v V, expiresAt time.Time) *Entry[K, V]
• func (l *LruList[K, V]) Remove(e *Entry[K, V]) V

Types ¶

type Entry ¶

type Entry[K comparable, V any] struct {

	// The LRU Key of this element.
	Key K

	// The Value stored with this element.
	Value V

	// The time this element would be cleaned up, optional
	ExpiresAt time.Time

	// The expiry bucket item was put in, optional
	ExpireBucket uint8
	// contains filtered or unexported fields
}

Entry is an LRU Entry

func (*Entry[K, V]) PrevEntry ¶

func (e *Entry[K, V]) PrevEntry() *Entry[K, V]

PrevEntry returns the previous list element or nil.

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]) KeyValues ¶

func (c *LRU[K, V]) KeyValues() map[K]V

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.

type LruList ¶

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

LruList represents a doubly linked list. The zero Value for LruList is an empty list ready to use.

func NewList ¶

func NewList[K comparable, V any]() *LruList[K, V]

NewList returns an initialized list.

func (*LruList[K, V]) Back ¶

func (l *LruList[K, V]) Back() *Entry[K, V]

Back returns the last element of list l or nil if the list is empty.

func (*LruList[K, V]) Init ¶

func (l *LruList[K, V]) Init() *LruList[K, V]

Init initializes or clears list l.

func (*LruList[K, V]) Length ¶

func (l *LruList[K, V]) Length() int

Length returns the number of elements of list l. The complexity is O(1).

func (*LruList[K, V]) MoveToFront ¶

func (l *LruList[K, V]) MoveToFront(e *Entry[K, V])

MoveToFront moves element e to the front of list l. If e is not an element of l, the list is not modified. The element must not be nil.

func (*LruList[K, V]) PushFront ¶

func (l *LruList[K, V]) PushFront(k K, v V) *Entry[K, V]

PushFront inserts a new element e with value v at the front of list l and returns e.

func (*LruList[K, V]) PushFrontExpirable ¶

func (l *LruList[K, V]) PushFrontExpirable(k K, v V, expiresAt time.Time) *Entry[K, V]

PushFrontExpirable inserts a new expirable element e with Value v at the front of list l and returns e.

func (*LruList[K, V]) Remove ¶

func (l *LruList[K, V]) Remove(e *Entry[K, V]) V

Remove removes e from its list, decrements l.len

Source Files ¶

lru.go