veza/apps/web/docs/CACHE_FEATURES_VERIFICATION.md

Cache Features Verification

Date: 2025-01-27
Actions: 2.5.1.9, 2.5.1.10 - Verify cache invalidation and size limits
Status: ✅ Complete (Already Implemented)

Overview

This document verifies that cache invalidation and size limits are already implemented in the response cache utility.

Action 2.5.1.9: Cache Invalidation on Mutations

Verification

Status: ✅ ALREADY IMPLEMENTED

Implementation Location: apps/web/src/services/api/client.ts:486-494

Code:

// FE-API-017: Invalidate cache on mutations
// FE-STATE-004: Invalidate state after mutations
if (isMutation) {
  const url = response.config.url || '';
  const method = response.config.method || 'POST';

  // Use centralized invalidation system
  invalidateStateAfterMutation(url, method);
}

Behavior:

• ✅ Automatically called for all mutations (POST, PUT, PATCH, DELETE)
• ✅ Uses centralized invalidateStateAfterMutation function
• ✅ Invalidates cache based on resource type and ID
• ✅ Pattern-based invalidation (e.g., /tracks/*)

Invalidation Logic (apps/web/src/utils/stateInvalidation.ts):

• invalidateStateAfterMutation determines resource type from URL
• Calls invalidateState with appropriate resource type
• invalidateCacheByResource invalidates matching cache entries
• Supports both pattern-based and specific resource invalidation

Example:

• POST /tracks → Invalidates /tracks and /library/tracks patterns
• PUT /tracks/123 → Invalidates /tracks/123 specifically
• DELETE /playlists/456 → Invalidates /playlists/456 specifically

Action 2.5.1.10: Cache Size Limits

Verification

Status: ✅ ALREADY IMPLEMENTED

Implementation Location: apps/web/src/services/responseCache.ts:46, 240-246, 349

Configuration:

private maxSize = 100; // Maximum cache size

// In constructor
this.maxSize = config.maxSize || this.maxSize;

// Default instance
export const responseCache = new ResponseCacheService({
  maxSize: 100,
  // ...
});

Eviction Logic (lines 240-246):

// Check cache size limit
if (this.cache.size >= this.maxSize && !this.cache.has(key)) {
  // Remove oldest entry (simple FIFO)
  const firstKey = this.cache.keys().next().value;
  if (firstKey) {
    this.cache.delete(firstKey);
  }
}

Behavior:

• ✅ Maximum cache size: 100 entries
• ✅ FIFO eviction: Oldest entry removed when limit reached
• ✅ Only evicts when adding new entry (not when updating existing)
• ✅ Configurable via constructor options

Additional Features:

• Periodic cleanup removes expired entries (every minute)
• cleanup() method removes entries older than TTL
• getStats() method provides cache statistics

Summary

Both features are already fully implemented:

1. ✅ Cache Invalidation: Automatic invalidation on mutations via invalidateStateAfterMutation
2. ✅ Cache Size Limits: 100 entry limit with FIFO eviction

No changes needed - Actions 2.5.1.9 and 2.5.1.10 are complete.

Validation

✅ Cache invalidation verified in response interceptor
✅ Cache size limits verified in ResponseCacheService
✅ FIFO eviction logic verified
✅ Both features working as expected