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API Response Caching with LRUCache

Use LRUCache to cache API responses and reduce network calls.

Implementation​

import { LRUCache } from '@msnkr/data-structures';

interface APIResponse {
  data: unknown;
  timestamp: number;
}

const apiCache = new LRUCache<string, APIResponse>({ capacity: 100 });

async function fetchWithCache(url: string): Promise<unknown> {
  // Check cache first
  const cached = apiCache.get(url);
  if (cached) {
    console.log('Cache hit!');
    return cached.data;
  }

  // Fetch from API
  const response = await fetch(url);
  const data = await response.json();

  // Store in cache
  apiCache.put(url, {
    data,
    timestamp: Date.now(),
  });

  return data;
}

// Usage
await fetchWithCache('/api/users'); // API call
await fetchWithCache('/api/users'); // Cache hit!

Benefits​

  • Reduced latency - Instant response for cached data
  • Lower server load - Fewer API calls
  • Automatic eviction - Least recently used items removed when full

See Also​