Throw exception if memcache misconfigured or missing

Instead of falling back to null memcache, throw exceptions.
Also throw file locking specific exceptions in case the class is not
available.

1 files changed, 15 insertions, 2 deletions

diff --git a/lib/private/memcache/factory.php b/lib/private/memcache/factory.php
index 5e3d857006c..320657a71ad 100644
--- a/lib/private/memcache/factory.php
+++ b/lib/private/memcache/factory.php
@@ -62,12 +62,25 @@ class Factory implements ICacheFactory {
 	{
 		$this->globalPrefix = $globalPrefix;
 
-		if (!($localCacheClass && $localCacheClass::isAvailable())) {
+		if (!$localCacheClass) {
 			$localCacheClass = self::NULL_CACHE;
 		}
-		if (!($distributedCacheClass && $distributedCacheClass::isAvailable())) {
+		if (!$distributedCacheClass) {
 			$distributedCacheClass = $localCacheClass;
 		}
+
+		if (!$localCacheClass::isAvailable()) {
+			throw new \OC\HintException(
+				'Missing memcache class ' . $localCacheClass . ' for local cache',
+				'Is the matching PHP module installed and enabled ?'
+			);
+		}
+		if (!$distributedCacheClass::isAvailable()) {
+			throw new \OC\HintException(
+				'Missing memcache class ' . $distributedCacheClass . ' for distributed cache',
+				'Is the matching PHP module installed and enabled ?'
+			);
+		}
 		if (!($lockingCacheClass && $lockingCacheClass::isAvailable())) {
 			// dont fallback since the fallback might not be suitable for storing lock
 			$lockingCacheClass = '\OC\Memcache\NullCache';