/**
* 简化的LRU缓存管理器
* 用于缓存 Ant Design 组件文档、API 定义、示例代码等
*/
interface CacheItem<T> {
value: T;
timestamp: number;
ttl?: number;
}
export class LRUCache<T = any> {
private cache: Map<string, CacheItem<T>>;
private maxSize: number;
private defaultTTL: number;
constructor(maxSize: number = 100, defaultTTL: number = 3600) {
this.cache = new Map();
this.maxSize = maxSize;
this.defaultTTL = defaultTTL * 1000; // 转换为毫秒
}
/**
* 设置缓存
*/
set(key: string, value: T, ttl?: number): this {
// 如果已存在，先删除（为了更新LRU顺序）
if (this.cache.has(key)) {
this.cache.delete(key);
}
// 如果缓存已满，删除最旧的项
if (this.cache.size >= this.maxSize) {
const firstKey = this.cache.keys().next().value;
if (firstKey) {
this.cache.delete(firstKey);
}
}
const item: CacheItem<T> = {
value,
timestamp: Date.now(),
ttl: ttl ? ttl * 1000 : this.defaultTTL
};
this.cache.set(key, item);
return this;
}
/**
* 获取缓存
*/
get(key: string): T | undefined {
const item = this.cache.get(key);
if (!item) {
return undefined;
}
// 检查是否过期
if (this.isExpired(item)) {
this.cache.delete(key);
return undefined;
}
// 更新LRU顺序：删除后重新添加
this.cache.delete(key);
this.cache.set(key, item);
return item.value;
}
/**
* 检查缓存是否存在且未过期
*/
has(key: string): boolean {
const item = this.cache.get(key);
if (!item) return false;
if (this.isExpired(item)) {
this.cache.delete(key);
return false;
}
return true;
}
/**
* 删除缓存
*/
delete(key: string): boolean {
return this.cache.delete(key);
}
/**
* 清空所有缓存
*/
clear(): void {
this.cache.clear();
}
/**
* 获取缓存大小
*/
getSize(): number {
this.cleanExpired();
return this.cache.size;
}
/**
* 获取所有有效的缓存键
*/
keys(): string[] {
this.cleanExpired();
return Array.from(this.cache.keys());
}
/**
* 检查项是否过期
*/
private isExpired(item: CacheItem<T>): boolean {
if (!item.ttl) return false;
return Date.now() - item.timestamp > item.ttl;
}
/**
* 清理过期项
*/
private cleanExpired(): void {
const now = Date.now();
for (const [key, item] of this.cache.entries()) {
if (this.isExpired(item)) {
this.cache.delete(key);
}
}
}
/**
* 获取缓存统计信息
*/
getStats() {
this.cleanExpired();
return {
size: this.cache.size,
maxSize: this.maxSize,
hitRate: 0
};
}
}
// 创建全局缓存实例
export const globalCache = new LRUCache(200, 600); // 200个项目，10分钟TTL
export default LRUCache;
