mediawiki-skins-Vector/includes/FeatureManagement/Requirements/TableOfContentsTreatmentRequirement.php
Jon Robson 9689974d0d AB test: Complain when TOC experiment setup incorrectly
Throw a runtime exception if the TOC experiment is setup correctly.
Otherwise this leads to confusion.

There must be 3 buckets, with 0 unsampled and equally weighted
control and experiment.

Bug: T313435
Change-Id: I09da238ff17b77a053b4dc132624ea19a86253b9
2022-08-30 11:59:42 -07:00

95 lines
2.4 KiB
PHP

<?php
namespace MediaWiki\Skins\Vector\FeatureManagement\Requirements;
use CentralIdLookup;
use Config;
use MediaWiki\Skins\Vector\Constants;
use MediaWiki\Skins\Vector\FeatureManagement\Requirement;
use RuntimeException;
use User;
/**
* Checks whether or not sticky Table of Contents should be shown.
*
* @unstable
*
* @package Vector\FeatureManagement\Requirements
* @internal
*/
final class TableOfContentsTreatmentRequirement implements Requirement {
/**
* @var Config
*/
private $config;
/**
* @var User
*/
private $user;
/**
* @var CentralIdLookup
*/
private $centralIdLookup;
/**
* @param Config $config
* @param User $user
* @param CentralIdLookup|null $centralIdLookup
*/
public function __construct(
Config $config,
User $user,
?CentralIdLookup $centralIdLookup
) {
$this->config = $config;
$this->user = $user;
$this->centralIdLookup = $centralIdLookup;
}
/**
* @inheritDoc
*/
public function getName(): string {
return Constants::REQUIREMENT_TABLE_OF_CONTENTS;
}
/**
* If A/B test is enabled check whether the user is logged in and bucketed.
*
* @inheritDoc
* @throws \ConfigException
*/
public function isMet(): bool {
$currentAbTest = $this->config->get( Constants::CONFIG_WEB_AB_TEST_ENROLLMENT );
$isTOCExperiment = $currentAbTest['name'] === 'skin-vector-toc-experiment';
if ( $isTOCExperiment && $currentAbTest['enabled'] && $this->user->isRegistered() ) {
$id = null;
$buckets = $currentAbTest['buckets'] ?? [];
$control = $buckets['control']['samplingRate'] ?? -1;
$unsampled = $buckets['unsampled']['samplingRate'] ?? -1;
$numBuckets = count( array_keys( $buckets ) );
if ( $unsampled !== 0 || $control !== 0.5 || $numBuckets !== 3 ) {
throw new RuntimeException( 'TableOfContents A/B test only supports 3 buckets with 0 unsampled.' );
}
if ( $this->centralIdLookup ) {
$id = $this->centralIdLookup->centralIdFromLocalUser( $this->user );
}
// $id will be 0 if the central ID lookup failed.
if ( !$id ) {
$id = $this->user->getId();
}
// This assume 100% sampling of logged-in users with roughly half
// in control or treatment buckets based on even or odd user ids.
// This does not cover unsampled users nor does it consider the
// sampling rates of any given bucket passed in via config.
return $id % 2 === 0;
}
return false;
}
}