b1c9ec74fa
A constant is not a variable. The type is hard-coded via the value and can never change. While the extra @var probably doesn't hurt much, it's redundant and error-prone and can't provide any additional information. Change-Id: Iee1f36a1905d9b9c6b26d0684b7848571f0c1733
109 lines
2.9 KiB
PHP
109 lines
2.9 KiB
PHP
<?php
|
|
/**
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
* http://www.gnu.org/copyleft/gpl.html
|
|
*
|
|
* @file
|
|
*/
|
|
|
|
declare( strict_types=1 );
|
|
|
|
namespace Wikimedia\Stats;
|
|
|
|
use TypeError;
|
|
use Wikimedia\Stats\Metrics\MetricInterface;
|
|
use Wikimedia\Stats\Metrics\NullMetric;
|
|
|
|
/**
|
|
* Singleton cache for Metric instances.
|
|
*
|
|
* For reuse and collision avoidance. Serves as the data source for Metric Emitters.
|
|
*
|
|
* @author Cole White
|
|
* @since 1.41
|
|
*/
|
|
class StatsCache {
|
|
|
|
public const DELIMITER = '.';
|
|
|
|
/** @var MetricInterface[] */
|
|
private array $cache = [];
|
|
|
|
/**
|
|
* Get a metric object from cache or null.
|
|
*
|
|
* @param string $component
|
|
* @param string $name
|
|
* @param string $expectedClass
|
|
* @return MetricInterface|null
|
|
* @throws TypeError If cached value is for a different metric type.
|
|
*/
|
|
public function get( string $component, string $name, string $expectedClass ) {
|
|
$key = self::cacheKey( $component, $name );
|
|
$metric = $this->cache[$key] ?? null;
|
|
if ( $metric !== null && get_class( $metric ) !== $expectedClass ) {
|
|
throw new TypeError( "Encountered metric name collision: $key defined as "
|
|
. get_class( $metric ) . " but $expectedClass was requested" );
|
|
}
|
|
return $metric;
|
|
}
|
|
|
|
/**
|
|
* Add a metric object to the cache.
|
|
*
|
|
* @param string $component
|
|
* @param string $name
|
|
* @param MetricInterface|NullMetric $metric
|
|
*/
|
|
public function set( string $component, string $name, $metric ): void {
|
|
$this->cache[self::cacheKey( $component, $name )] = $metric;
|
|
}
|
|
|
|
/**
|
|
* Get all metrics from cache.
|
|
*
|
|
* @return MetricInterface[]
|
|
*/
|
|
public function getAllMetrics(): array {
|
|
return $this->cache;
|
|
}
|
|
|
|
/**
|
|
* Clears the cache.
|
|
*
|
|
* @return void
|
|
*/
|
|
public function clear(): void {
|
|
$this->cache = [];
|
|
}
|
|
|
|
/**
|
|
* Get the metric formatted name.
|
|
*
|
|
* Takes the provided name and constructs a more specific name by combining
|
|
* component and name.
|
|
*
|
|
* @param string $component
|
|
* @param string $name
|
|
* @return string
|
|
*/
|
|
private static function cacheKey( string $component, string $name ): string {
|
|
// mitigate collision of empty-component metric with a component metric
|
|
if ( $component !== '' ) {
|
|
return implode( self::DELIMITER, [ $component, $name ] );
|
|
}
|
|
return $name;
|
|
}
|
|
}
|