K8s Doctor MCP

/** * Simple in-memory cache with TTL * * @author zerry */ interface CacheEntry<T> { value: T; expiresAt: number; } /** * Simple memory cache with TTL support */ export class MemoryCache<T> { private cache = new Map<string, CacheEntry<T>>(); private defaultTTL: number; /** * @param defaultTTL Default time-to-live in milliseconds (default: 30 seconds) */ constructor(defaultTTL: number = 30000) { this.defaultTTL = defaultTTL; } /** * Get value from cache * * @param key Cache key * @returns Cached value or undefined if not found or expired */ get(key: string): T | undefined { const entry = this.cache.get(key); if (!entry) { return undefined; } // Check if expired if (Date.now() > entry.expiresAt) { this.cache.delete(key); return undefined; } return entry.value; } /** * Set value in cache * * @param key Cache key * @param value Value to cache * @param ttl Time-to-live in milliseconds (optional, uses default if not provided) */ set(key: string, value: T, ttl?: number): void { const expiresAt = Date.now() + (ttl ?? this.defaultTTL); this.cache.set(key, { value, expiresAt }); } /** * Delete value from cache * * @param key Cache key */ delete(key: string): void { this.cache.delete(key); } /** * Clear all cache entries */ clear(): void { this.cache.clear(); } /** * Get cache size */ size(): number { return this.cache.size; } /** * Clean up expired entries */ cleanup(): void { const now = Date.now(); for (const [key, entry] of this.cache.entries()) { if (now > entry.expiresAt) { this.cache.delete(key); } } } } /** * Get or compute cached value * * @param cache Cache instance * @param key Cache key * @param computeFn Function to compute value if not cached * @param ttl Optional TTL override * @returns Cached or computed value */ export async function getOrCompute<T>( cache: MemoryCache<T>, key: string, computeFn: () => Promise<T>, ttl?: number ): Promise<T> { // Try to get from cache first const cached = cache.get(key); if (cached !== undefined) { return cached; } // Compute value const value = await computeFn(); // Cache it cache.set(key, value, ttl); return value; }