import NodeCache from 'node-cache';
import { logger } from '../utils/logger.js';
export class CacheService {
private cache: NodeCache;
private hitCount = 0;
private missCount = 0;
constructor(defaultTtl: number = 300) {
this.cache = new NodeCache({
stdTTL: defaultTtl,
checkperiod: 60,
useClones: false,
deleteOnExpire: true,
});
this.cache.on('expired', (key: string) => {
logger.debug(`Cache key expired: ${key}`);
});
this.cache.on('del', (key: string) => {
logger.debug(`Cache key deleted: ${key}`);
});
}
async getOrSet<T>(
key: string,
fetchFn: () => Promise<T>,
ttl?: number
): Promise<T> {
const cached = this.cache.get<T>(key);
if (cached !== undefined) {
this.hitCount++;
logger.debug(`Cache hit: ${key}`);
return cached;
}
this.missCount++;
logger.debug(`Cache miss: ${key}`);
try {
const data = await fetchFn();
this.cache.set(key, data, ttl || 300);
logger.debug(`Cache set: ${key} (TTL: ${ttl || 'default'})`);
return data;
} catch (error) {
logger.error(`Failed to fetch data for cache key: ${key}`, error);
throw error;
}
}
get<T>(key: string): T | undefined {
const value = this.cache.get<T>(key);
if (value !== undefined) {
this.hitCount++;
} else {
this.missCount++;
}
return value;
}
set<T>(key: string, value: T, ttl?: number): boolean {
return this.cache.set(key, value, ttl || 300);
}
del(key: string): number {
return this.cache.del(key);
}
flush(): void {
this.cache.flushAll();
logger.info('Cache flushed');
}
getStats(): any {
const cacheStats = this.cache.getStats();
return {
...cacheStats,
hitRate: this.hitCount / (this.hitCount + this.missCount) || 0,
hitCount: this.hitCount,
missCount: this.missCount,
};
}
}
