From 58c81f5b86a454e51af247117d3c0d3adabbc5d4 Mon Sep 17 00:00:00 2001
From: Matthias Mullie <git@mullie.eu>
Date: Wed, 2 Sep 2015 15:02:36 +0200
Subject: [PATCH] Decode Memcached keys before returning getMulti result

Keys are sent to Memcached encoded. However, getMulti()
will respond in [key => value] format. The keys it
responds with should not be the encoded versions, or
callers won't be able to map them to the results.

Bug: T111138
Change-Id: I0d821b1219a492be8e93453f0249c78f18e24533
---
 includes/objectcache/MemcachedPeclBagOStuff.php      | 9 +++++++--
 includes/objectcache/MemcachedPhpBagOStuff.php       | 8 +++++++-
 tests/phpunit/includes/objectcache/BagOStuffTest.php | 8 ++++++--
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/includes/objectcache/MemcachedPeclBagOStuff.php b/includes/objectcache/MemcachedPeclBagOStuff.php
index 7e6a4d7074..1b2c8db62e 100644
--- a/includes/objectcache/MemcachedPeclBagOStuff.php
+++ b/includes/objectcache/MemcachedPeclBagOStuff.php
@@ -236,8 +236,13 @@ class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
 	public function getMulti( array $keys, $flags = 0 ) {
 		$this->debugLog( 'getMulti(' . implode( ', ', $keys ) . ')' );
 		$callback = array( $this, 'encodeKey' );
-		$result = $this->client->getMulti( array_map( $callback, $keys ) );
-		$result = $result ?: array(); // must be an array
+		$encodedResult = $this->client->getMulti( array_map( $callback, $keys ) );
+		$encodedResult = $encodedResult ?: array(); // must be an array
+		$result = array();
+		foreach ( $encodedResult as $key => $value ) {
+			$key = $this->decodeKey( $key );
+			$result[$key] = $value;
+		}
 		return $this->checkResult( false, $result );
 	}
 
diff --git a/includes/objectcache/MemcachedPhpBagOStuff.php b/includes/objectcache/MemcachedPhpBagOStuff.php
index 69792ada56..6f0ba58820 100644
--- a/includes/objectcache/MemcachedPhpBagOStuff.php
+++ b/includes/objectcache/MemcachedPhpBagOStuff.php
@@ -59,7 +59,13 @@ class MemcachedPhpBagOStuff extends MemcachedBagOStuff {
 
 	public function getMulti( array $keys, $flags = 0 ) {
 		$callback = array( $this, 'encodeKey' );
-		return $this->client->get_multi( array_map( $callback, $keys ) );
+		$encodedResult = $this->client->get_multi( array_map( $callback, $keys ) );
+		$result = array();
+		foreach ( $encodedResult as $key => $value ) {
+			$key = $this->decodeKey( $key );
+			$result[$key] = $value;
+		}
+		return $result;
 	}
 
 	/**
diff --git a/tests/phpunit/includes/objectcache/BagOStuffTest.php b/tests/phpunit/includes/objectcache/BagOStuffTest.php
index f5814e4483..b684006202 100644
--- a/tests/phpunit/includes/objectcache/BagOStuffTest.php
+++ b/tests/phpunit/includes/objectcache/BagOStuffTest.php
@@ -138,21 +138,25 @@ class BagOStuffTest extends MediaWikiTestCase {
 	public function testGetMulti() {
 		$value1 = array( 'this' => 'is', 'a' => 'test' );
 		$value2 = array( 'this' => 'is', 'another' => 'test' );
+		$value3 = array( 'testing a key that may be encoded when sent to cache backend' );
 
 		$key1 = wfMemcKey( 'test1' );
 		$key2 = wfMemcKey( 'test2' );
+		$key3 = wfMemcKey( 'will-%-encode' ); // internally, MemcachedBagOStuffs will encode to will-%25-encode
 
 		$this->cache->add( $key1, $value1 );
 		$this->cache->add( $key2, $value2 );
+		$this->cache->add( $key3, $value3 );
 
 		$this->assertEquals(
-			$this->cache->getMulti( array( $key1, $key2 ) ),
-			array( $key1 => $value1, $key2 => $value2 )
+			array( $key1 => $value1, $key2 => $value2, $key3 => $value3 ),
+			$this->cache->getMulti( array( $key1, $key2, $key3 ) )
 		);
 
 		// cleanup
 		$this->cache->delete( $key1 );
 		$this->cache->delete( $key2 );
+		$this->cache->delete( $key3 );
 	}
 
 	/**
-- 
2.20.1