From f13b86527a8b52b14df665fcbd52aec66b5b0738 Mon Sep 17 00:00:00 2001
From: Corinna Hillebrand <corinna.hillebrand@wikimedia.de>
Date: Tue, 28 Oct 2025 19:05:18 +0100
Subject: [PATCH] Specify CEST Berlin timezone when parsing start and end dates
 of campaign

---
 public/index.php                                     |  2 ++
 src/Utils/CampaignConfigurationLoader.php            |  4 ++--
 tests/Unit/Utils/CampaignConfigurationLoaderTest.php | 10 ++++++++++
 tests/bootstrap.php                                  |  2 ++
 4 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/public/index.php b/public/index.php
index bf1eee5..5fa1479 100644
--- a/public/index.php
+++ b/public/index.php
@@ -7,6 +7,8 @@
 
 require __DIR__ . '/../vendor/autoload.php';
 
+date_default_timezone_set( 'Europe/Berlin' );
+
 // The check is to ensure we don't use .env in production
 if ( !isset( $_SERVER['APP_ENV'] ) && !isset( $_ENV['APP_ENV'] ) ) {
 	if ( !class_exists( Dotenv::class ) ) {
diff --git a/src/Utils/CampaignConfigurationLoader.php b/src/Utils/CampaignConfigurationLoader.php
index da7962a..bf12e4f 100644
--- a/src/Utils/CampaignConfigurationLoader.php
+++ b/src/Utils/CampaignConfigurationLoader.php
@@ -95,8 +95,8 @@ private function buildCampaignFromData( string $campaignName, array $campaignDat
 
 		return new Campaign(
 			$campaignName,
-			new \DateTime( $start ),
-			new \DateTime( $end ),
+			new \DateTime( $start, new \DateTimeZone( 'Europe/Berlin' ) ),
+			new \DateTime( $end, new \DateTimeZone( 'Europe/Berlin' ) ),
 			$trafficLimit,
 			$category,
 			new SystemRandomIntegerGenerator(),
diff --git a/tests/Unit/Utils/CampaignConfigurationLoaderTest.php b/tests/Unit/Utils/CampaignConfigurationLoaderTest.php
index 3100f46..3ea9a8e 100644
--- a/tests/Unit/Utils/CampaignConfigurationLoaderTest.php
+++ b/tests/Unit/Utils/CampaignConfigurationLoaderTest.php
@@ -47,6 +47,16 @@ public function test_given_campaigns_are_loaded_then_loaded_campaign_data_is_cor
 		$this->assertEquals( 'B18WPDE_02_180511_top_ctrl_last', $bucketA->getBanner( 10 ) );
 	}
 
+	public function test_loaded_campaign_start_end_dates_are_in_CET_Berlin_timezone(): void {
+		$loader = new CampaignConfigurationLoader( self::TEST_VALID_CAMPAIGN_CONFIGURATION_FILE );
+		$collection = $loader->getCampaignCollection();
+
+		$campaign = $collection->getCampaign( new DateTime( "2018-11-31 01:23:45" ) );
+
+		$this->assertNotNull( $campaign );
+		$this->assertSame( 'Europe/Berlin', $campaign->getEnd()->getTimezone()->getName() );
+	}
+
 	public function test_given_broken_bucket_campaign_configuration_then_errors_are_caught(): void {
 		$loader = new CampaignConfigurationLoader(
 			self::TEST_BROKEN_BUCKET_CAMPAIGN_CONFIGURATION_FILE
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index f6ad901..77687a0 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -5,6 +5,8 @@
 
 require dirname( __DIR__ ) . '/vendor/autoload.php';
 
+date_default_timezone_set( 'Europe/Berlin' );
+
 if ( file_exists( dirname( __DIR__ ) . '/config/bootstrap.php' ) ) {
 	require dirname( __DIR__ ) . '/config/bootstrap.php';
 } elseif ( method_exists( Dotenv::class, 'bootEnv' ) ) {