快速调用即可从Firebase的多个节点中删除价值

Question

当用户点击按钮时，我希望能够使用一个调用删除单独的父节点中的2个值。目前，我刚刚将第二个数据库删除调用放置在第一个调用的完成块中。

 guard let uid = Auth.auth().currentUser?.uid else {return}
    guard let convoId = conversation?.conversationId else {return}
    let ref = Database.database().reference()

    let leaveChatAction = UIAlertAction(title: "Leave", style: .destructive) { (action) in
        ref.child("users").child(uid).child("conversations").child(convoId).removeValue(completionBlock: { (error, ref) in

            if let error = error {
                print ("Couldn't delete convo ID from users node:", error)
            }

            ref.child("conversation_users").child(convoId).child(uid).removeValue(completionBlock: { (error, ref) in

                if let error = error {
                    print ("Couldn't delete userID from convo node:", error)
                }

                self.navigationController?.popViewController(animated: true)

            })
        })
    }