F5 Cloud Status MCP Server

/** * Cache service for F5 Status MCP Server * Implements TTL-based caching with type safety */ import { CacheError } from '../utils/errors.js'; import { logger } from '../utils/logger.js'; /** * Cache entry with expiration */ interface CacheEntry<T> { data: T; expiry: number; } /** * Cache service class */ export class CacheService { private cache: Map<string, CacheEntry<unknown>>; private readonly name: string; constructor(name: string = 'default') { this.cache = new Map(); this.name = name; } /** * Get value from cache or fetch if missing/expired */ async get<T>(key: string, ttl: number, fetcher: () => Promise<T>): Promise<T> { try { // Check cache const cached = this.cache.get(key) as CacheEntry<T> | undefined; if (cached && cached.expiry > Date.now()) { logger.debug(`Cache hit for key: ${key}`, { name: this.name }); return cached.data; } // Cache miss or expired logger.debug(`Cache miss for key: ${key}`, { name: this.name }); const data = await fetcher(); // Store in cache this.set(key, data, ttl); return data; } catch (error) { logger.error(`Cache get error for key: ${key}`, error); throw new CacheError(`Failed to get cache entry: ${key}`, error); } } /** * Set value in cache with TTL */ set<T>(key: string, data: T, ttl: number): void { try { const expiry = Date.now() + ttl; this.cache.set(key, { data, expiry }); logger.debug(`Cache set for key: ${key}`, { name: this.name, ttl, expiry: new Date(expiry).toISOString(), }); } catch (error) { logger.error(`Cache set error for key: ${key}`, error); throw new CacheError(`Failed to set cache entry: ${key}`, error); } } /** * Check if key exists and is not expired */ has(key: string): boolean { const cached = this.cache.get(key); if (!cached) return false; if (cached.expiry <= Date.now()) { this.delete(key); return false; } return true; } /** * Get value directly from cache (without fetcher) */ getDirect<T>(key: string): T | undefined { const cached = this.cache.get(key) as CacheEntry<T> | undefined; if (!cached) return undefined; if (cached.expiry <= Date.now()) { this.delete(key); return undefined; } return cached.data; } /** * Delete entry from cache */ delete(key: string): boolean { const deleted = this.cache.delete(key); if (deleted) { logger.debug(`Cache delete for key: ${key}`, { name: this.name }); } return deleted; } /** * Clear all cache entries */ clear(): void { const size = this.cache.size; this.cache.clear(); logger.info(`Cache cleared`, { name: this.name, entriesCleared: size }); } /** * Get cache statistics */ getStats(): { size: number; entries: Array<{ key: string; expiresIn: number; expiresAt: string; }>; } { const now = Date.now(); const entries = Array.from(this.cache.entries()).map(([key, entry]) => ({ key, expiresIn: Math.max(0, entry.expiry - now), expiresAt: new Date(entry.expiry).toISOString(), })); return { size: this.cache.size, entries, }; } /** * Clean expired entries */ cleanExpired(): number { const now = Date.now(); let cleaned = 0; for (const [key, entry] of this.cache.entries()) { if (entry.expiry <= now) { this.cache.delete(key); cleaned++; } } if (cleaned > 0) { logger.debug(`Cleaned expired cache entries`, { name: this.name, count: cleaned, }); } return cleaned; } /** * Invalidate cache entries matching pattern */ invalidatePattern(pattern: RegExp): number { let invalidated = 0; for (const key of this.cache.keys()) { if (pattern.test(key)) { this.cache.delete(key); invalidated++; } } if (invalidated > 0) { logger.info(`Invalidated cache entries by pattern`, { name: this.name, pattern: pattern.toString(), count: invalidated, }); } return invalidated; } } /** * Create a cache service instance */ export function createCacheService(name?: string): CacheService { return new CacheService(name); }