includes/libs/Stats/Metrics/MetricInterface.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  * @file
  18  */
  19
  20 namespace Wikimedia\Stats\Metrics;
  21
  22 use Psr\Log\LoggerInterface;
  23 use Wikimedia\Stats\Sample;
  24
  25 /**
  26  * Metric Interface
  27  *
  28  * @author Cole White
  29  * @since 1.41
  30  */
  31 interface MetricInterface {
  32         /**
  33          * @param BaseMetricInterface $baseMetric
  34          * @param LoggerInterface $logger
  35          */
  36         public function __construct( BaseMetricInterface $baseMetric, LoggerInterface $logger );
  37
  38         /** @return string */
  39         public function getName(): string;
  40
  41         /** @return string */
  42         public function getComponent(): string;
  43
  44         /** @return float */
  45         public function getSampleRate(): float;
  46
  47         /** @return string */
  48         public function getTypeIndicator(): string;
  49
  50         /**
  51          * Returns subset of samples corresponding to sample rate setting.
  52          *
  53          * @return Sample[]
  54          */
  55         public function getSamples(): array;
  56
  57         /**
  58          * Sets sample rate on a new metric instance.
  59          *
  60          * @param float $sampleRate
  61          * @return CounterMetric|GaugeMetric|TimingMetric|NullMetric
  62          */
  63         public function setSampleRate( float $sampleRate );
  64
  65         /**
  66          * Returns the list of defined label keys.
  67          *
  68          * @return string[]
  69          */
  70         public function getLabelKeys(): array;
  71
  72         /**
  73          * Adds a label $key with $value.
  74          *
  75          * @param string $key
  76          * @param string $value
  77          * @return CounterMetric|GaugeMetric|TimingMetric|NullMetric
  78          */
  79         public function setLabel( string $key, string $value );
  80
  81         /**
  82          * Copies metric operation to StatsD at provided namespace.
  83          *
  84          * @param string $statsdNamespace
  85          * @return CounterMetric|GaugeMetric|TimingMetric|NullMetric
  86          */
  87         public function copyToStatsdAt( string $statsdNamespace );
  88
  89         /**
  90          * Returns metric with cleared labels.
  91          *
  92          * @return CounterMetric|GaugeMetric|TimingMetric|NullMetric
  93          */
  94         public function fresh();
  95 }