Tracking Cache Activity with Laravel Events

Laravel's cache event system enables comprehensive monitoring of cache operations throughout your application. These events provide insights into cache performance and usage patterns.

Laravel fires specific events for different cache activities:

use Illuminate\Cache\Events\{
    CacheHit,
    CacheMissed,
    KeyForgotten,
    KeyWritten
};

You can create listeners to respond to these events and gather performance data or trigger additional actions based on cache behavior.

use Illuminate\Support\Facades\Event;
 
Event::listen(function (CacheHit $event) {
    Log::info("Cache hit for key: {$event->key}");
});
 
Event::listen(function (CacheMissed $event) {
    Log::info("Cache miss for key: {$event->key}");
});

Here's a comprehensive cache analytics system that tracks all cache operations:

use Illuminate\Support\Facades\Event;
use Illuminate\Support\Facades\DB;
 
class CacheAnalyticsService
{
    public function registerListeners()
    {
        Event::listen(function (CacheHit $event) {
            $this->trackCacheOperation('hit', [
                'cache_key' => $event->key,
                'store' => $event->store ?? 'default',
                'timestamp' => now()
            ]);
        });
 
        Event::listen(function (CacheMissed $event) {
            $this->trackCacheOperation('miss', [
                'cache_key' => $event->key,
                'store' => $event->store ?? 'default',
                'timestamp' => now()
            ]);
        });
 
        Event::listen(function (KeyWritten $event) {
            $this->trackCacheOperation('write', [
                'cache_key' => $event->key,
                'expiry_seconds' => $event->seconds,
                'store' => $event->store ?? 'default',
                'timestamp' => now()
            ]);
        });
 
        Event::listen(function (KeyForgotten $event) {
            $this->trackCacheOperation('delete', [
                'cache_key' => $event->key,
                'store' => $event->store ?? 'default',
                'timestamp' => now()
            ]);
        });
    }
 
    private function trackCacheOperation(string $operation, array $metadata)
    {
        DB::table('cache_analytics')->insert([
            'operation_type' => $operation,
            'cache_key' => $metadata['cache_key'],
            'store_name' => $metadata['store'],
            'expiry_time' => $metadata['expiry_seconds'] ?? null,
            'recorded_at' => $metadata['timestamp']
        ]);
    }
}

Event monitoring can impact performance, so you can disable it per cache store in your configuration when needed.