groupMember->getMembers($group_id); } public function addGroupMember($group_id, $user_id) { return $this->groupMember->addUser($group_id, $user_id); } public function removeGroupMember($group_id, $user_id) { return $this->groupMember->removeUser($group_id, $user_id); } public function isGroupMember($group_id, $user_id) { return $this->groupMember->isMember($group_id, $user_id); } }