friendica-5847 Console Cache List command doesn't work

- Added $prefix to all CacheDriver
- Moved hostname magic to CacheDriver
- Added test for getAllKeys()

src/Core/Cache/AbstractCacheDriver.php

@@ -17,8 +17,55 @@ abstract class AbstractCacheDriver extends BaseObject
 	 * @param string $key	The original key
 	 * @return string		The cache key used for the cache
 	 */
-	protected function getCacheKey($key) {
+	protected function getCacheKey($key)
+	{
 		// We fetch with the hostname as key to avoid problems with other applications
 		return self::getApp()->get_hostname() . ":" . $key;
 	}
+
+	/**
+	 * @param array $keys   A list of cached keys
+	 * @return array        A list of original keys
+	 */
+	protected function getOriginalKeys($keys)
+	{
+		if (empty($keys)) {
+			return [];
+		} else {
+			// Keys are prefixed with the node hostname, let's remove it
+			array_walk($keys, function (&$value) {
+				$value = preg_replace('/^' . self::getApp()->get_hostname() . ':/', '', $value);
+			});
+
+			sort($keys);
+
+			return $keys;
+		}
+	}
+
+	/**
+	 * Filters a list for a given prefix
+	 *
+	 * @param array $list the list
+	 * @param string|null $prefix the prefix
+	 *
+	 * @return array the filtered list
+	 */
+	protected function filterPrefix($list, $prefix = null)
+	{
+		if (empty($prefix)) {
+			return array_keys($list);
+		} else {
+			$result = [];
+
+			foreach (array_keys($list) as $key) {
+				if (strpos($key, $prefix) === 0) {
+					array_push($result, $key);
+				}
+			}
+
+			return $result;
+		}
+
+	}
 }