Stats: add timing start and stop helper functions

Adds a start() and stop() helper functions to simplfy measuring the timing value.

Bug: T240685
Change-Id: Ifecb4ffc679dc46b9806aecb8b947b67c7884a1b

1 files changed, 26 insertions, 0 deletions

diff --git a/includes/libs/Stats/Metrics/TimingMetric.php b/includes/libs/Stats/Metrics/TimingMetric.php
index 1c9a38697448..545dbdf9bd40 100644
--- a/includes/libs/Stats/Metrics/TimingMetric.php
+++ b/includes/libs/Stats/Metrics/TimingMetric.php
@@ -52,6 +52,9 @@ class TimingMetric implements MetricInterface {
 	/** @var LoggerInterface */
 	private LoggerInterface $logger;
 
+	/** @var float|null */
+	private ?float $startTime = null;
+
 	/** @inheritDoc */
 	public function __construct( $baseMetric, $logger ) {
 		$this->baseMetric = $baseMetric;
@@ -59,6 +62,29 @@ class TimingMetric implements MetricInterface {
 	}
 
 	/**
+	 * Starts a timer.
+	 *
+	 * @return void
+	 */
+	public function start(): void {
+		$this->startTime = microtime( true );
+	}
+
+	/**
+	 * Stops a running timer.
+	 *
+	 * @return void
+	 */
+	public function stop(): void {
+		if ( $this->startTime === null ) {
+			trigger_error( "Stats: stop() called before start() for metric '{$this->getName()}'", E_USER_WARNING );
+			return;
+		}
+		$this->observe( ( microtime( true ) - $this->startTime ) * 1000 );
+		$this->startTime = null;
+	}
+
+	/**
 	 * Records a previously calculated observation.
 	 *
 	 * @param float $value