Feature Request: Implement Caching

[jaythorat]

Description

This issue tracks the implementation of Caching to enhance performance of the DNS server.

Objective:

• Store DNS query results temporarily to reduce latency and improve performance.

Benefits:

• Faster response time for repeated queries.
• Reduced load on upstream servers and lower bandwidth usage.
• Increased reliability during upstream server downtime.

Tasks:

• Implement an in-memory cache using Python's dict or an external library like cachetools.
• Add logic to check the cache before querying upstream servers.
• Implement cache expiration based on the TTL value.
• Use a Least Recently Used (LRU) strategy or similar to manage memory efficiently.
• Optionally integrate with Redis or Memcached for distributed caching.

References:

• Caching in Python