38 lines
927 B
PHP
38 lines
927 B
PHP
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<?php
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namespace Wikimedia\Telemetry;
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use Wikimedia\Assert\Assert;
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/**
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* A {@link SamplerInterface} implementation that samples a given percentage of root spans,
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* while respecting sampling decisions made by other samplers for a given trace.
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*
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* @since 1.43
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* @internal
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*/
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class ProbabilisticSampler implements SamplerInterface {
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/**
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* The chance of sampling a root span, as a percentage (0-100).
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* @var int
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*/
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private int $percentChance;
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public function __construct( int $percentChance ) {
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Assert::parameter(
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$percentChance >= 0 && $percentChance <= 100,
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'$percentChance',
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'must be between 0 and 100 inclusive'
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);
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$this->percentChance = $percentChance;
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}
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/** @inheritDoc */
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public function shouldSample( ?SpanContext $parentSpanContext ): bool {
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if ( $parentSpanContext !== null ) {
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return $parentSpanContext->isSampled();
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}
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return mt_rand( 1, 100 ) <= $this->percentChance;
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}
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}
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