feat: backend core - auth, user, role, permission, device, webhook, monitoring, cache, repository, service, middleware, API handlers

internal/cache/l1.go

@@ -0,0 +1,171 @@
+package cache
+
+import (
+	"sync"
+	"time"
+)
+
+const (
+	// maxItems 是L1Cache的最大条目数
+	// 超过此限制后将淘汰最久未使用的条目
+	maxItems = 10000
+)
+
+// CacheItem 缓存项
+type CacheItem struct {
+	Value      interface{}
+	Expiration int64
+}
+
+// Expired 判断缓存项是否过期
+func (item *CacheItem) Expired() bool {
+	return item.Expiration > 0 && time.Now().UnixNano() > item.Expiration
+}
+
+// L1Cache L1本地缓存（支持LRU淘汰策略）
+type L1Cache struct {
+	items map[string]*CacheItem
+	mu    sync.RWMutex
+	// accessOrder 记录key的访问顺序，用于LRU淘汰
+	// 第一个是最久未使用的，最后一个是最近使用的
+	accessOrder []string
+}
+
+// NewL1Cache 创建L1缓存
+func NewL1Cache() *L1Cache {
+	return &L1Cache{
+		items: make(map[string]*CacheItem),
+	}
+}
+
+// Set 设置缓存
+func (c *L1Cache) Set(key string, value interface{}, ttl time.Duration) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	var expiration int64
+	if ttl > 0 {
+		expiration = time.Now().Add(ttl).UnixNano()
+	}
+
+	// 如果key已存在，更新访问顺序
+	if _, exists := c.items[key]; exists {
+		c.items[key] = &CacheItem{
+			Value:      value,
+			Expiration: expiration,
+		}
+		c.updateAccessOrder(key)
+		return
+	}
+
+	// 检查是否超过最大容量，进行LRU淘汰
+	if len(c.items) >= maxItems {
+		c.evictLRU()
+	}
+
+	c.items[key] = &CacheItem{
+		Value:      value,
+		Expiration: expiration,
+	}
+	c.accessOrder = append(c.accessOrder, key)
+}
+
+// evictLRU 淘汰最久未使用的条目
+func (c *L1Cache) evictLRU() {
+	if len(c.accessOrder) == 0 {
+		return
+	}
+	// 淘汰最久未使用的（第一个）
+	oldest := c.accessOrder[0]
+	delete(c.items, oldest)
+	c.accessOrder = c.accessOrder[1:]
+}
+
+// removeFromAccessOrder 从访问顺序中移除key
+func (c *L1Cache) removeFromAccessOrder(key string) {
+	for i, k := range c.accessOrder {
+		if k == key {
+			c.accessOrder = append(c.accessOrder[:i], c.accessOrder[i+1:]...)
+			return
+		}
+	}
+}
+
+// updateAccessOrder 更新访问顺序，将key移到最后（最近使用）
+func (c *L1Cache) updateAccessOrder(key string) {
+	for i, k := range c.accessOrder {
+		if k == key {
+			// 移除当前位置
+			c.accessOrder = append(c.accessOrder[:i], c.accessOrder[i+1:]...)
+			// 添加到末尾
+			c.accessOrder = append(c.accessOrder, key)
+			return
+		}
+	}
+}
+
+// Get 获取缓存
+func (c *L1Cache) Get(key string) (interface{}, bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	item, ok := c.items[key]
+	if !ok {
+		return nil, false
+	}
+
+	if item.Expired() {
+		delete(c.items, key)
+		c.removeFromAccessOrder(key)
+		return nil, false
+	}
+
+	// 更新访问顺序
+	c.updateAccessOrder(key)
+
+	return item.Value, true
+}
+
+// Delete 删除缓存
+func (c *L1Cache) Delete(key string) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	delete(c.items, key)
+	c.removeFromAccessOrder(key)
+}
+
+// Clear 清空缓存
+func (c *L1Cache) Clear() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	c.items = make(map[string]*CacheItem)
+	c.accessOrder = make([]string, 0)
+}
+
+// Size 获取缓存大小
+func (c *L1Cache) Size() int {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+
+	return len(c.items)
+}
+
+// Cleanup 清理过期缓存
+func (c *L1Cache) Cleanup() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	now := time.Now().UnixNano()
+	keysToDelete := make([]string, 0)
+	for key, item := range c.items {
+		if item.Expiration > 0 && now > item.Expiration {
+			keysToDelete = append(keysToDelete, key)
+		}
+	}
+	for _, key := range keysToDelete {
+		delete(c.items, key)
+		c.removeFromAccessOrder(key)
+	}
+}