<?php declare(strict_types=1);
/*
* This file is part of the Monolog package.
*
* (c) Jordi Boggiano <[email protected]>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Monolog\Handler;
use Monolog\Formatter\FormatterInterface;
/**
* Sampling handler
*
* A sampled event stream can be useful for logging high frequency events in
* a production environment where you only need an idea of what is happening
* and are not concerned with capturing every occurrence. Since the decision to
* handle or not handle a particular event is determined randomly, the
* resulting sampled log is not guaranteed to contain 1/N of the events that
* occurred in the application, but based on the Law of large numbers, it will
* tend to be close to this ratio with a large number of attempts.
*
* @author Bryan Davis <[email protected]>
* @author Kunal Mehta <[email protected]>
*/
class SamplingHandler extends AbstractHandler implements ProcessableHandlerInterface, FormattableHandlerInterface
{
use ProcessableHandlerTrait;
/**
* @var callable|HandlerInterface $handler
*/
protected $handler;
/**
* @var int $factor
*/
protected $factor;
/**
* @psalm-param HandlerInterface|callable(array, HandlerInterface): HandlerInterface $handler
*
* @param callable|HandlerInterface $handler Handler or factory callable($record|null, $samplingHandler).
* @param int $factor Sample factor (e.g. 10 means every ~10th record is sampled)
*/
public function __construct($handler, int $factor)
{
parent::__construct();
$this->handler = $handler;
$this->factor = $factor;
if (!$this->handler instanceof HandlerInterface && !is_callable($this->handler)) {
throw new \RuntimeException("The given handler (".json_encode($this->handler).") is not a callable nor a Monolog\Handler\HandlerInterface object");
}
}
public function isHandling(array $record): bool
{
return $this->getHandler($record)->isHandling($record);
}
public function handle(array $record): bool
{
if ($this->isHandling($record) && mt_rand(1, $this->factor) === 1) {
if ($this->processors) {
$record = $this->processRecord($record);
}
$this->getHandler($record)->handle($record);
}
return false === $this->bubble;
}
/**
* Return the nested handler
*
* If the handler was provided as a factory callable, this will trigger the handler's instantiation.
*
* @return HandlerInterface
*/
public function getHandler(array $record = null)
{
if (!$this->handler instanceof HandlerInterface) {
$this->handler = ($this->handler)($record, $this);
if (!$this->handler instanceof HandlerInterface) {
throw new \RuntimeException("The factory callable should return a HandlerInterface");
}
}
return $this->handler;
}
/**
* {@inheritdoc}
*/
public function setFormatter(FormatterInterface $formatter): HandlerInterface
{
$handler = $this->getHandler();
if ($handler instanceof FormattableHandlerInterface) {
$handler->setFormatter($formatter);
return $this;
}
throw new \UnexpectedValueException('The nested handler of type '.get_class($handler).' does not support formatters.');
}
/**
* {@inheritdoc}
*/
public function getFormatter(): FormatterInterface
{
$handler = $this->getHandler();
if ($handler instanceof FormattableHandlerInterface) {
return $handler->getFormatter();
}
throw new \UnexpectedValueException('The nested handler of type '.get_class($handler).' does not support formatters.');
}
}