RunningTimer.php

Go to the documentation of this file.

<?php
namespace Wikimedia\Stats\Metrics;
 
use Wikimedia\Timestamp\ConvertibleTimestamp;
 
class RunningTimer {
 
    private $metric;
    private ?float $startTime;
    private array $workingLabels;
 
    public function __construct( float $startTime, TimingMetric $metric, array $initialLabels ) {
        $this->startTime = $startTime;
        $this->metric = $metric;
        $this->workingLabels = $initialLabels;
    }
 
    public function setLabel( string $key, string $value ) {
        $this->workingLabels[$key] = $value;
        return $this;
    }
 
    public function setLabels( array $labels ) {
        $this->workingLabels = $labels;
        return $this;
    }
 
    public function stop() {
        if ( $this->startTime === null ) {
            trigger_error(
                "Stats: ({$this->metric->getName()}) cannot call stop() more than once on a RunningTimer.",
                E_USER_WARNING
            );
            return;
        }
        // T406170 - move setting labels near recording the sample.
        //
        // Downstream label changes can affect upstream usage because they're the same
        // metric instance.  Here, we'll assume any labels set when the metric was
        // initially declared or changed against the RunningTimer instance are correct
        // and set them before sample capture time.
        $this->metric = $this->metric->setLabels( $this->workingLabels );
        $this->metric->observeNanoseconds( ConvertibleTimestamp::hrtime() - $this->startTime );
        $this->startTime = null;
    }
}