PHP code example of sanmai / sliding-window-counter

    
        
<?php
require_once('vendor/autoload.php');

/* Start to develop here. Best regards https://php-download.com/ */

    

sanmai / sliding-window-counter example snippets

// Import necessary classes
use SlidingWindowCounter\SlidingWindowCounter;
use SlidingWindowCounter\Cache\MemcachedAdapter;

// Create a counter that tracks hourly data for the past 24 hours
$counter = new SlidingWindowCounter(
    'visitor-counter',     // Name for your counter
    3600,                  // Window size: 3600 seconds (1 hour)
    3600 * 24,             // Keep data for 24 hours
    new MemcachedAdapter($memcached)
);

// Count a visit from this IP address
$counter->increment($_SERVER['REMOTE_ADDR']);

// You can also count by other keys
$counter->increment('user_' . $user_id);
$counter->increment('product_' . $product_id);

// Import the result class to access constants
use SlidingWindowCounter\AnomalyDetectionResult;

// Check if current activity is abnormal
$result = $counter->detectAnomaly($_SERVER['REMOTE_ADDR']);

if ($result->isAnomaly()) {
    // Something unusual is happening!
    $direction = $result->getDirection(); // Returns DIRECTION_UP, DIRECTION_DOWN, or DIRECTION_NONE
    
    if ($direction === \SlidingWindowCounter\AnomalyDetectionResult::DIRECTION_UP) {
        // Unusually high activity
        echo "Spike detected! Current: " . $result->getLatest();
        echo "Normal range: " . $result->getLow() . " to " . $result->getHigh();
    }
}

// Get all stats as an array (values rounded to 2 decimal places by default)
$stats = $result->toArray();

// Or access individual values
$mean = $result->getMean();
$stdDev = $result->getStandardDeviation();
$currentValue = $result->getLatest();

// You can also get historical variance directly
$variance = $counter->getHistoricVariance($_SERVER['REMOTE_ADDR']);
$sampleCount = $variance->getCount();

// Higher sensitivity (1 standard deviation) - detects more anomalies
$result = $counter->detectAnomaly($_SERVER['REMOTE_ADDR'], 1);

// Default sensitivity (2 standard deviations)
$result = $counter->detectAnomaly($_SERVER['REMOTE_ADDR']);

// Lower sensitivity (3 standard deviations) - only extreme outliers
$result = $counter->detectAnomaly($_SERVER['REMOTE_ADDR'], 3);

// Extremely low sensitivity (5 standard deviations) - only detects extreme outliers
$result = $counter->detectAnomaly($_SERVER['REMOTE_ADDR'], 5);

// For regular Memcached
use SlidingWindowCounter\Cache\MemcachedAdapter;
$adapter = new MemcachedAdapter($memcached);

// For WordPress sites (uses WP's object cache)
use SlidingWindowCounter\Cache\WPCacheAdapter;
$adapter = new WPCacheAdapter($wp_object_cache);

use SlidingWindowCounter\Cache\CounterCache;

class RedisAdapter implements CounterCache 
{
    private $redis;
    
    public function __construct(Redis $redis) 
    {
        $this->redis = $redis;
    }
    
    public function increment(string $cache_name, string $cache_key, int $ttl, int $step)
    {
        $key = "{$cache_name}:{$cache_key}";
        $this->redis->setnx($key, 0); // Create if not exists
        $this->redis->expire($key, $ttl);
        return $this->redis->incrby($key, $step);
    }
    
    public function get(string $cache_name, string $cache_key): ?int
    {
        $value = $this->redis->get("{$cache_name}:{$cache_key}");
        return is_numeric($value) ? (int)$value : null;
    }
}