Caching

[nelsojona]

Add Enhanced Caching with Debug Support

This PR implements an improved caching mechanism for API responses with debug logging capabilities.

Changes

• Added normalize_cache_key_args() function to standardize cache key generation
• Implemented thread-safe caching with TTL and LRU eviction
• Added debug logging for cache hits/misses with emoji indicators
• Added --debug-cache CLI flag for easy debugging
• Added documentation in src/utils/README.md

Features

• Consistent cache key generation that handles:
  • Positional and keyword arguments
  • Nested dictionaries and lists
  • Date objects
• Debug logging shows:
  • 💾 Cache MISS - When new data is stored
  • 🎯 Cache HIT - When cached data is retrieved
• Thread-safe implementation for concurrent access
• TTL-based cache expiration
• LRU eviction when cache is full

Usage

Enable debug logging via code:

from utils.cache import set_debug
set_debug(True)

Or via CLI:

poetry run python src/main.py --ticker AAPL --debug-cache

Testing

Tested with multiple API endpoints and verified:

• Cache hits/misses are logged correctly
• Keys are generated consistently
• Thread safety under concurrent access
• TTL expiration works as expected