/**
* Acquire a Redis connection.
*
* @access protected
* @param string [Optiona] Server group key.
* Example: 'cache' would look up $wgRedisServers['cached']
* Default: Uses the first index of $wgRedisServers.
* @param array [Optional] Additional options, will merge and overwrite default options.
* - connectTimeout : The timeout for new connections, in seconds.
* Optional, default is 1 second.
* - persistent : Set this to true to allow connections to persist across
* multiple web requests. False by default.
* - password : The authentication password, will be sent to Redis in clear text.
* Optional, if it is unspecified, no AUTH command will be sent.
* - serializer : Set to "php", "igbinary", or "none". Default is "php".
* @param boolean [Optional] Force a new connection, useful when forking processes.
* @return mixed Object RedisConnRef or false on failure.
*/
public static function getClient($group = null, $options = [], $newConnection = false)
{
global $wgRedisServers;
if (!extension_loaded('redis')) {
throw new MWException(__METHOD__ . " - The PHP Redis extension is not available. Please enable it on the server to use RedisCache.");
}
if (empty($wgRedisServers) || !is_array($wgRedisServers)) {
MWDebug::log(__METHOD__ . " - \$wgRedisServers must be configured for RedisCache to function.");
return false;
}
if (empty($group)) {
$group = 0;
$server = current($wgRedisServers);
} else {
$server = $wgRedisServers[$group];
}
if ($newConnection === false && array_key_exists($group, self::$servers)) {
return self::$servers[$group];
}
if (empty($server) || !is_array($server)) {
throw new MWException(__METHOD__ . " - An invalid server group key was passed.");
}
$pool = \RedisConnectionPool::singleton(array_merge($server['options'], $options));
$redis = $pool->getConnection($server['host'] . ":" . $server['port']);
//Concatenate these together for MediaWiki weirdness so it can split them later.
if ($redis instanceof RedisConnRef) {
//Set up any extra options. RedisConnectionPool does not handle the prefix automatically.
if (!empty($server['options']['prefix'])) {
$redis->setOption(Redis::OPT_PREFIX, $server['options']['prefix']);
}
try {
$pong = $redis->ping();
if ($pong === '+PONG') {
self::$servers[$group] = $redis;
} else {
$redis = false;
}
} catch (RedisException $e) {
//People using HAProxy will find it will lie about a Redis cluster being healthy when the master is down, but the slaves are up. Doing a PING will cause an immediate disconnect.
self::$lastError = $e->getMessage();
$redis = false;
}
}
return $redis;
}
