1 files changed, 77 insertions, 0 deletions
diff --git a/www/wiki/tests/phpunit/includes/libs/SamplingStatsdClientTest.php b/www/wiki/tests/phpunit/includes/libs/SamplingStatsdClientTest.php
new file mode 100644
index 00000000..7bd16115
--- /dev/null
+++ b/www/wiki/tests/phpunit/includes/libs/SamplingStatsdClientTest.php
@@ -0,0 +1,77 @@
+<?php
+
+use Liuggio\StatsdClient\Entity\StatsdData;
+use Liuggio\StatsdClient\Sender\SenderInterface;
+
+/**
+ * @covers SamplingStatsdClient
+ */
+class SamplingStatsdClientTest extends PHPUnit\Framework\TestCase {
+
+	use MediaWikiCoversValidator;
+
+	/**
+	 * @dataProvider samplingDataProvider
+	 */
+	public function testSampling( $data, $sampleRate, $seed, $expectWrite ) {
+		$sender = $this->getMockBuilder( SenderInterface::class )->getMock();
+		$sender->expects( $this->any() )->method( 'open' )->will( $this->returnValue( true ) );
+		if ( $expectWrite ) {
+			$sender->expects( $this->once() )->method( 'write' )
+				->with( $this->anything(), $this->equalTo( $data ) );
+		} else {
+			$sender->expects( $this->never() )->method( 'write' );
+		}
+		if ( defined( 'MT_RAND_PHP' ) ) {
+			mt_srand( $seed, MT_RAND_PHP );
+		} else {
+			mt_srand( $seed );
+		}
+		$client = new SamplingStatsdClient( $sender );
+		$client->send( $data, $sampleRate );
+	}
+
+	public function samplingDataProvider() {
+		$unsampled = new StatsdData();
+		$unsampled->setKey( 'foo' );
+		$unsampled->setValue( 1 );
+
+		$sampled = new StatsdData();
+		$sampled->setKey( 'foo' );
+		$sampled->setValue( 1 );
+		$sampled->setSampleRate( '0.1' );
+
+		return [
+			// $data, $sampleRate, $seed, $expectWrite
+			[ $unsampled, 1, 0 /*0.44*/, true ],
+			[ $sampled, 1, 0 /*0.44*/, false ],
+			[ $sampled, 1, 4 /*0.03*/, true ],
+			[ $unsampled, 0.1, 0 /*0.44*/, false ],
+			[ $sampled, 0.5, 0 /*0.44*/, false ],
+			[ $sampled, 0.5, 4 /*0.03*/, false ],
+		];
+	}
+
+	public function testSetSamplingRates() {
+		$matching = new StatsdData();
+		$matching->setKey( 'foo.bar' );
+		$matching->setValue( 1 );
+
+		$nonMatching = new StatsdData();
+		$nonMatching->setKey( 'oof.bar' );
+		$nonMatching->setValue( 1 );
+
+		$sender = $this->getMockBuilder( SenderInterface::class )->getMock();
+		$sender->expects( $this->any() )->method( 'open' )->will( $this->returnValue( true ) );
+		$sender->expects( $this->once() )->method( 'write' )->with( $this->anything(),
+			$this->equalTo( $nonMatching ) );
+
+		$client = new SamplingStatsdClient( $sender );
+		$client->setSamplingRates( [ 'foo.*' => 0.2 ] );
+
+		mt_srand( 0 ); // next random is 0.44
+		$client->send( $matching );
+		mt_srand( 0 );
+		$client->send( $nonMatching );
+	}
+}