91 lines
1.6 KiB
Go
91 lines
1.6 KiB
Go
package cache
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import (
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"sync"
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)
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type Cache struct {
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data map[string]struct{}
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order []string
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maxItems int
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mu sync.RWMutex
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}
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func New(maxItems int) *Cache {
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if maxItems <= 0 {
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maxItems = 1000
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}
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return &Cache{
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data: make(map[string]struct{}, maxItems),
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order: make([]string, 0, maxItems),
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maxItems: maxItems,
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}
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}
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func (c *Cache) Add(value string) {
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c.mu.Lock()
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defer c.mu.Unlock()
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if _, exists := c.data[value]; !exists {
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if len(c.order) >= c.maxItems {
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delete(c.data, c.order[0])
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c.order = c.order[1:]
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}
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c.data[value] = struct{}{}
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c.order = append(c.order, value)
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}
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}
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func (c *Cache) AddMultiple(values map[string]bool) {
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c.mu.Lock()
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defer c.mu.Unlock()
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for value, exists := range values {
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if !exists {
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if _, exists := c.data[value]; !exists {
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if len(c.order) >= c.maxItems {
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delete(c.data, c.order[0])
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c.order = c.order[1:]
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}
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c.data[value] = struct{}{}
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c.order = append(c.order, value)
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}
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}
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}
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}
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func (c *Cache) Get(index int) (string, bool) {
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c.mu.RLock()
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defer c.mu.RUnlock()
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if index < 0 || index >= len(c.order) {
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return "", false
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}
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return c.order[index], true
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}
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func (c *Cache) GetMultiple(values []string) map[string]bool {
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c.mu.RLock()
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defer c.mu.RUnlock()
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result := make(map[string]bool, len(values))
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for _, value := range values {
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if _, exists := c.data[value]; exists {
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result[value] = true
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}
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}
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return result
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}
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func (c *Cache) Exists(value string) bool {
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c.mu.RLock()
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defer c.mu.RUnlock()
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_, exists := c.data[value]
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return exists
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}
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func (c *Cache) Len() int {
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c.mu.RLock()
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defer c.mu.RUnlock()
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return len(c.order)
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}
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