<?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\Logger;
use Monolog\Formatter\FormatterInterface;
/**
* Handler to only pass log messages when a certain threshold of number of messages is reached.
*
* This can be useful in cases of processing a batch of data, but you're for example only interested
* in case it fails catastrophically instead of a warning for 1 or 2 events. Worse things can happen, right?
*
* Usage example:
*
* ```
* $log = new Logger('application');
* $handler = new SomeHandler(...)
*
* // Pass all warnings to the handler when more than 10 & all error messages when more then 5
* $overflow = new OverflowHandler($handler, [Logger::WARNING => 10, Logger::ERROR => 5]);
*
* $log->pushHandler($overflow);
*```
*
* @author Kris Buist <[email protected]>
*/
class OverflowHandler extends AbstractHandler implements FormattableHandlerInterface
{
/** @var HandlerInterface */
private $handler;
/** @var int[] */
private $thresholdMap = [
Logger::DEBUG => 0,
Logger::INFO => 0,
Logger::NOTICE => 0,
Logger::WARNING => 0,
Logger::ERROR => 0,
Logger::CRITICAL => 0,
Logger::ALERT => 0,
Logger::EMERGENCY => 0,
];
/**
* Buffer of all messages passed to the handler before the threshold was reached
*
* @var mixed[][]
*/
private $buffer = [];
/**
* @param HandlerInterface $handler
* @param int[] $thresholdMap Dictionary of logger level => threshold
* @param int|string $level The minimum logging level at which this handler will be triggered
* @param bool $bubble
*/
public function __construct(
HandlerInterface $handler,
array $thresholdMap = [],
$level = Logger::DEBUG,
bool $bubble = true
) {
$this->handler = $handler;
foreach ($thresholdMap as $thresholdLevel => $threshold) {
$this->thresholdMap[$thresholdLevel] = $threshold;
}
parent::__construct($level, $bubble);
}
/**
* Handles a record.
*
* All records may be passed to this method, and the handler should discard
* those that it does not want to handle.
*
* The return value of this function controls the bubbling process of the handler stack.
* Unless the bubbling is interrupted (by returning true), the Logger class will keep on
* calling further handlers in the stack with a given log record.
*
* @param array $record The record to handle
*
* @return Boolean true means that this handler handled the record, and that bubbling is not permitted.
* false means the record was either not processed or that this handler allows bubbling.
*/
public function handle(array $record): bool
{
if ($record['level'] < $this->level) {
return false;
}
$level = $record['level'];
if (!isset($this->thresholdMap[$level])) {
$this->thresholdMap[$level] = 0;
}
if ($this->thresholdMap[$level] > 0) {
// The overflow threshold is not yet reached, so we're buffering the record and lowering the threshold by 1
$this->thresholdMap[$level]--;
$this->buffer[$level][] = $record;
return false === $this->bubble;
}
if ($this->thresholdMap[$level] == 0) {
// This current message is breaking the threshold. Flush the buffer and continue handling the current record
foreach ($this->buffer[$level] ?? [] as $buffered) {
$this->handler->handle($buffered);
}
$this->thresholdMap[$level]--;
unset($this->buffer[$level]);
}
$this->handler->handle($record);
return false === $this->bubble;
}
/**
* {@inheritdoc}
*/
public function setFormatter(FormatterInterface $formatter): HandlerInterface
{
if ($this->handler instanceof FormattableHandlerInterface) {
$this->handler->setFormatter($formatter);
return $this;
}
throw new \UnexpectedValueException('The nested handler of type '.get_class($this->handler).' does not support formatters.');
}
/**
* {@inheritdoc}
*/
public function getFormatter(): FormatterInterface
{
if ($this->handler instanceof FormattableHandlerInterface) {
return $this->handler->getFormatter();
}
throw new \UnexpectedValueException('The nested handler of type '.get_class($this->handler).' does not support formatters.');
}
}