Cache Prefix Configuration Analyzer

Analyzer ID	Category	Severity	Time To Fix
cache-prefix-configuration	✅ Reliability	High	5 minutes

What This Checks

• Detects when shared cache drivers (redis, memcached, dynamodb, database) are in use without a configured prefix
• Verifies both the global cache.prefix and store-specific prefixes to ensure they’re non-empty
• Flags prefixes that are too generic (e.g., laravel_cache, app, cache) or identical to other tenants
• Provides location hints (line numbers in config/cache.php) for quick remediation

Why It Matters

• Multi-tenant collisions: On shared Redis/Memcached clusters, generic prefixes cause one project to overwrite another’s entries
• Production stability: Cache collisions lead to inconsistent sessions, stale feature flags, and corrupted cached data
• Best practices: Laravel recommends slugging APP_NAME and appending _cache; forgetting this leaves you exposed when deploying to shared environments (e.g., Vapor, multi-app Redis)

How to Fix

Quick Fix (1 minute)

1. Edit config/cache.php:

'prefix' => env('CACHE_PREFIX', Str::slug(env('APP_NAME', 'laravel'), '_').'_cache'),

2. For store-specific needs (e.g., redis only):

'redis' => [
    'driver' => 'redis',
    'connection' => 'cache',
    'prefix' => env('CACHE_PREFIX', 'myapp_cache'),
],

3. Set CACHE_PREFIX=myapp_production_cache in .env.

Proper Fix (5 minutes)

1. Slug your APP_NAME: Ensure APP_NAME is unique per environment (DEV vs PROD) to make the default slug unique
2. Override per store: For multi-tenant Redis clusters, set stores.redis.prefix to a tenant-specific slug
3. Automate: Add an environment-specific fallback so ephemeral environments (review apps) auto-generate unique prefixes (Str::uuid()) on boot
4. Test: Write integration tests ensuring different .env configurations yield different cache keys (e.g., store and retrieve a known key)
5. Monitor: Consider namespacing keys (e.g., myapp:prod:) for easier debugging in Redis CLI

References

• Laravel Cache Configuration
• Laravel Vapor Cache Best Practices

Related Analyzers

• Cache Status Analyzer - Validates cache connectivity and functionality
• Queue Timeout Configuration Analyzer - Ensures queue timeout and retry_after values are properly configured
• Composer Validation Analyzer - Ensures composer.json is valid and follows best practices