From 9ead461970970326cc417630b22a0ae7028c906f Mon Sep 17 00:00:00 2001
From: Baha <bmansurov@wikimedia.org>
Date: Thu, 7 Feb 2019 11:10:09 -0500
Subject: [PATCH] Expose external link additions and deletions

Needed for links event stream.

Bug: T214706
Change-Id: Ie93c8d90c2f69d7a08b8a6e9a0a5bb8266d4dd51
---
 RELEASE-NOTES-1.33                            |  2 +
 includes/deferred/LinksUpdate.php             | 47 ++++++++++++++++++-
 .../includes/deferred/LinksUpdateTest.php     | 29 +++++++++++-
 3 files changed, 75 insertions(+), 3 deletions(-)

diff --git a/RELEASE-NOTES-1.33 b/RELEASE-NOTES-1.33
index 8105446e9f..b21a65aab5 100644
--- a/RELEASE-NOTES-1.33
+++ b/RELEASE-NOTES-1.33
@@ -48,6 +48,8 @@ production.
   Content::getNativeData() for text-based content models.
 * (T210814) SVGs are now by default displayed in wiki language on image
   pages.
+* (T214706) LinksUpdate::getAddedExternalLinks() and
+  LinksUpdate::getRemovedExternalLinks() were introduced.
 
 === External library changes in 1.33 ===
 
diff --git a/includes/deferred/LinksUpdate.php b/includes/deferred/LinksUpdate.php
index 937196d943..7c7cabd2b8 100644
--- a/includes/deferred/LinksUpdate.php
+++ b/includes/deferred/LinksUpdate.php
@@ -84,6 +84,16 @@ class LinksUpdate extends DataUpdate implements EnqueueableDataUpdate {
 	 */
 	private $linkDeletions = null;
 
+	/**
+	 * @var null|array Added external links if calculated.
+	 */
+	private $externalLinkInsertions = null;
+
+	/**
+	 * @var null|array Deleted external links if calculated.
+	 */
+	private $externalLinkDeletions = null;
+
 	/**
 	 * @var null|array Added properties if calculated.
 	 */
@@ -234,11 +244,14 @@ class LinksUpdate extends DataUpdate implements EnqueueableDataUpdate {
 
 		# External links
 		$existingEL = $this->getExistingExternals();
+		$this->externalLinkDeletions = $this->getExternalDeletions( $existingEL );
+		$this->externalLinkInsertions = $this->getExternalInsertions(
+			$existingEL );
 		$this->incrTableUpdate(
 			'externallinks',
 			'el',
-			$this->getExternalDeletions( $existingEL ),
-			$this->getExternalInsertions( $existingEL ) );
+			$this->externalLinkDeletions,
+			$this->externalLinkInsertions );
 
 		# Language links
 		$existingLL = $this->getExistingInterlangs();
@@ -1099,6 +1112,36 @@ class LinksUpdate extends DataUpdate implements EnqueueableDataUpdate {
 		return $result;
 	}
 
+	/**
+	 * Fetch external links added by this LinksUpdate. Only available after
+	 * the update is complete.
+	 * @since 1.33
+	 * @return null|array Array of Strings
+	 */
+	public function getAddedExternalLinks() {
+		if ( $this->externalLinkInsertions === null ) {
+			return null;
+		}
+		$result = [];
+		foreach ( $this->externalLinkInsertions as $key => $value ) {
+			$result[] = $value['el_to'];
+		}
+		return $result;
+	}
+
+	/**
+	 * Fetch external links removed by this LinksUpdate. Only available after
+	 * the update is complete.
+	 * @since 1.33
+	 * @return null|array Array of Strings
+	 */
+	public function getRemovedExternalLinks() {
+		if ( $this->externalLinkDeletions === null ) {
+			return null;
+		}
+		return array_keys( $this->externalLinkDeletions );
+	}
+
 	/**
 	 * Fetch page properties added by this LinksUpdate.
 	 * Only available after the update is complete.
diff --git a/tests/phpunit/includes/deferred/LinksUpdateTest.php b/tests/phpunit/includes/deferred/LinksUpdateTest.php
index 90a5ed17ff..cd3ddfa8e8 100644
--- a/tests/phpunit/includes/deferred/LinksUpdateTest.php
+++ b/tests/phpunit/includes/deferred/LinksUpdateTest.php
@@ -118,6 +118,8 @@ class LinksUpdateTest extends MediaWikiLangTestCase {
 
 	/**
 	 * @covers ParserOutput::addExternalLink
+	 * @covers LinksUpdate::getAddedExternalLinks
+	 * @covers LinksUpdate::getRemovedExternalLinks
 	 */
 	public function testUpdate_externallinks() {
 		/** @var ParserOutput $po */
@@ -125,7 +127,7 @@ class LinksUpdateTest extends MediaWikiLangTestCase {
 
 		$po->addExternalLink( "http://testing.com/wiki/Foo" );
 
-		$this->assertLinksUpdate(
+		$update = $this->assertLinksUpdate(
 			$t,
 			$po,
 			'externallinks',
@@ -135,6 +137,31 @@ class LinksUpdateTest extends MediaWikiLangTestCase {
 				[ 'http://testing.com/wiki/Foo', 'http://com.testing./wiki/Foo' ],
 			]
 		);
+
+		$this->assertArrayEquals( [
+			"http://testing.com/wiki/Foo"
+		], $update->getAddedExternalLinks() );
+
+		$po = new ParserOutput();
+		$po->setTitleText( $t->getPrefixedText() );
+		$po->addExternalLink( 'http://testing.com/wiki/Bar' );
+		$update = $this->assertLinksUpdate(
+			$t,
+			$po,
+			'externallinks',
+			'el_to, el_index',
+			'el_from = ' . self::$testingPageId,
+			[
+				[ 'http://testing.com/wiki/Bar', 'http://com.testing./wiki/Bar' ],
+			]
+		);
+
+		$this->assertArrayEquals( [
+			"http://testing.com/wiki/Bar"
+		], $update->getAddedExternalLinks() );
+		$this->assertArrayEquals( [
+			"http://testing.com/wiki/Foo"
+		], $update->getRemovedExternalLinks() );
 	}
 
 	/**
-- 
2.20.1