private static function buildPorts(array $env) { return array_reduce(array_keys($env), function ($linkPorts, $name) use($env) { if (preg_match("/^PORT_(?<port>[0-9]+)_(?<protocol>((TCP)|(UDP)))\$/", $name, $matches) === 1) { $linkPorts[] = Port::build($env, $matches['port'], $matches['protocol']); } return $linkPorts; }, []); }