import NodeCache from 'node-cache';
import { Logger } from './Logger.js';
const DEFAULT_CONFIG = {
stdTTL: 3600, // 1 hour default TTL
checkperiod: 120 // Check for expired keys every 2 minutes
};
export class CacheManager {
cache;
version = 'v1';
logger;
constructor(config = {}) {
this.logger = Logger.create('CacheManager');
this.cache = new NodeCache({
...DEFAULT_CONFIG,
...config
});
// Set up cache event listeners
this.cache.on('set', (key, value) => {
this.logger.debug('Cache entry set', { key, hasValue: !!value });
});
this.cache.on('del', (key, value) => {
this.logger.debug('Cache entry deleted', { key });
});
this.cache.on('expired', (key, value) => {
this.logger.debug('Cache entry expired', { key });
});
}
createKey(toolName, params) {
const sortedParams = Object.keys(params)
.sort()
.reduce((acc, key) => {
acc[key] = params[key];
return acc;
}, {});
return `${this.version}:${toolName}:${JSON.stringify(sortedParams)}`;
}
async cacheResponse(key, fetchFn, ttl) {
try {
// Check if data exists in cache
const cached = this.cache.get(key);
if (cached !== undefined) {
this.logger.debug('Cache hit', { key });
return cached;
}
// Fetch fresh data
this.logger.debug('Cache miss, fetching fresh data', { key });
const result = await fetchFn();
// Store in cache
this.cache.set(key, result, ttl ?? DEFAULT_CONFIG.stdTTL);
this.logger.debug('Data cached successfully', { key, ttl: ttl ?? DEFAULT_CONFIG.stdTTL });
return result;
}
catch (error) {
this.logger.error('Error in cacheResponse', { key }, error);
// Try to return stale data if available
const staleData = this.cache.get(key);
if (staleData !== undefined) {
this.logger.warn('Returning stale data due to fetch error', { key });
return {
...staleData,
warning: "Data may be stale due to fetch error"
};
}
throw error;
}
}
async getOrFetch(key, fetchFn, ttl) {
// This method is now an alias for cacheResponse for backward compatibility
return this.cacheResponse(key, fetchFn, ttl);
}
invalidate(key) {
this.logger.debug('Invalidating cache entry', { key });
this.cache.del(key);
}
invalidatePattern(pattern) {
const keys = this.cache.keys();
const matchingKeys = keys.filter(key => key.includes(pattern));
if (matchingKeys.length > 0) {
this.logger.debug('Invalidating cache entries by pattern', { pattern, count: matchingKeys.length });
this.cache.del(matchingKeys);
}
return matchingKeys.length;
}
clear() {
this.logger.info('Clearing all cache entries');
this.cache.flushAll();
}
getStats() {
return this.cache.getStats();
}
// Create a singleton instance for global use
static instance;
static getInstance(config) {
if (!CacheManager.instance) {
CacheManager.instance = new CacheManager(config);
}
return CacheManager.instance;
}
}
