52 lines
1.3 KiB
Go
52 lines
1.3 KiB
Go
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package cache
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import "sync"
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// LRU Discards the least recently used items first. This algorithm
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// requires keeping track of what was used when.
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type LRU struct {
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// Mutex is used for handling the concurrent
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// read/write requests for cache
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sync.Mutex
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// cache holds the all cache values
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cache Cache
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}
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// NewLRU creates a thread-safe LRU cache
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func NewLRU(size int) Cache {
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return &LRU{
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cache: NewLRUNoTS(size),
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}
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}
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// Get returns the value of a given key if it exists, every get item will be
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// moved to the head of the linked list for keeping track of least recent used
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// item
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func (l *LRU) Get(key string) (interface{}, error) {
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l.Lock()
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defer l.Unlock()
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return l.cache.Get(key)
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}
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// Set sets or overrides the given key with the given value, every set item will
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// be moved or prepended to the head of the linked list for keeping track of
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// least recent used item. When the cache is full, last item of the linked list
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// will be evicted from the cache
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func (l *LRU) Set(key string, val interface{}) error {
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l.Lock()
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defer l.Unlock()
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return l.cache.Set(key, val)
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}
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// Delete deletes the given key-value pair from cache, this function doesnt
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// return an error if item is not in the cache
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func (l *LRU) Delete(key string) error {
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l.Lock()
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defer l.Unlock()
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return l.cache.Delete(key)
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}
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