Composer Package README MCP Server

import { logger } from '../utils/logger.js'; import { CacheEntry, CacheOptions } from '../types/index.js'; import { CACHE_CONSTANTS } from '../utils/constants.js'; export class MemoryCache { private cache = new Map<string, CacheEntry<unknown>>(); private readonly defaultTtl: number; private readonly maxSize: number; private readonly cleanupInterval: NodeJS.Timeout; constructor(options: CacheOptions = {}) { this.defaultTtl = options.ttl || CACHE_CONSTANTS.DEFAULT_TTL_MS; this.maxSize = options.maxSize || CACHE_CONSTANTS.DEFAULT_MAX_SIZE_BYTES; // Clean up expired entries periodically this.cleanupInterval = setInterval(() => { this.cleanup(); }, CACHE_CONSTANTS.CLEANUP_INTERVAL_MS); } set<T>(key: string, value: T, ttl?: number): void { const actualTtl = ttl || this.defaultTtl; const timestamp = Date.now(); const entry: CacheEntry<T> = { data: value, timestamp, ttl: actualTtl, }; // Check if adding this entry would exceed max size if (this.wouldExceedMaxSize(key, entry)) { this.evictLeastRecentlyUsed(); } this.cache.set(key, entry); logger.debug(`Cache set: ${key} (TTL: ${actualTtl}ms)`); } get<T>(key: string): T | null { const entry = this.cache.get(key) as CacheEntry<T> | undefined; if (!entry) { logger.debug(`Cache miss: ${key}`); return null; } const now = Date.now(); if (now - entry.timestamp > entry.ttl) { this.cache.delete(key); logger.debug(`Cache expired: ${key}`); return null; } // Update timestamp for LRU entry.timestamp = now; logger.debug(`Cache hit: ${key}`); return entry.data; } delete(key: string): boolean { const deleted = this.cache.delete(key); if (deleted) { logger.debug(`Cache deleted: ${key}`); } return deleted; } clear(): void { this.cache.clear(); logger.info('Cache cleared'); } has(key: string): boolean { const entry = this.cache.get(key); if (!entry) { return false; } const now = Date.now(); if (now - entry.timestamp > entry.ttl) { this.cache.delete(key); return false; } return true; } size(): number { return this.cache.size; } getStats(): { size: number; memoryUsage: number; hitRate: number } { const memoryUsage = this.estimateMemoryUsage(); return { size: this.cache.size, memoryUsage, hitRate: 0, // TODO: Implement hit rate tracking }; } private cleanup(): void { const now = Date.now(); let expiredCount = 0; for (const [key, entry] of this.cache.entries()) { if (now - entry.timestamp > entry.ttl) { this.cache.delete(key); expiredCount++; } } if (expiredCount > 0) { logger.debug(`Cache cleanup: removed ${expiredCount} expired entries`); } } private wouldExceedMaxSize<T>(key: string, entry: CacheEntry<T>): boolean { const currentSize = this.estimateMemoryUsage(); const entrySize = this.estimateEntrySize(key, entry); return currentSize + entrySize > this.maxSize; } private evictLeastRecentlyUsed(): void { let oldestKey: string | null = null; let oldestTimestamp = Date.now(); for (const [key, entry] of this.cache.entries()) { if (entry.timestamp < oldestTimestamp) { oldestTimestamp = entry.timestamp; oldestKey = key; } } if (oldestKey) { this.cache.delete(oldestKey); logger.debug(`Cache LRU eviction: ${oldestKey}`); } } private estimateMemoryUsage(): number { let totalSize = 0; for (const [key, entry] of this.cache.entries()) { totalSize += this.estimateEntrySize(key, entry); } return totalSize; } private estimateEntrySize<T>(key: string, entry: CacheEntry<T>): number { // Rough estimation: key + JSON serialized data + metadata const keySize = key.length * 2; // UTF-16 const dataSize = JSON.stringify(entry.data).length * 2; const metadataSize = 24; // timestamp + ttl + object overhead return keySize + dataSize + metadataSize; } destroy(): void { clearInterval(this.cleanupInterval); this.cache.clear(); logger.info('Cache destroyed'); } } // Create cache key helpers export const createCacheKey = { packageInfo: (packageName: string, version: string): string => `pkg_info:${packageName}:${version}`, packageReadme: (packageName: string, version: string): string => `pkg_readme:${packageName}:${version}`, searchResults: (query: string, limit: number, type?: string): string => { const queryHash = Buffer.from(query).toString('base64'); const params = [queryHash, limit.toString()]; if (type !== undefined) params.push(`t:${type}`); return `search:${params.join(':')}`; }, downloadStats: (packageName: string): string => `stats:${packageName}:${new Date().toISOString().split('T')[0]}`, // Include date for daily invalidation }; // Global cache instance export const cache = new MemoryCache();