最近项目接到新需求，需要用Unity 客户端（发送端）控制另一台 Unity 客户端（接收端），中间用UDP服务器做数据中转。
先测试一下连通性，我用 Python 搞了个服务器 demo。
在正式开发之前，先做一个连通性测试，于是用python写UDP服务器demo，并部署到宝塔面板上。
代码
server.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-import socket
import sys
import subprocess
import time
import threadingclass UDPServer:def __init__(self, host='0.0.0.0', port=7789):self.host = hostself.port = portprint(f"Server initializing on {host}:{port}")self.sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)self.clients = {}self.running = Truedef start(self):try:self.sock.bind((self.host, self.port))print("Server started successfully")except Exception as e:print(f"Server start failed: {e}")returncleanup_thread = threading.Thread(target=self.cleanup_inactive_clients)cleanup_thread.daemon = Truecleanup_thread.start()while self.running:try:data, addr = self.sock.recvfrom(1024)message = data.decode('utf-8')self.handle_message(message, addr)except Exception as e:print(f"Error: {e}")def handle_message(self, data, addr):try:commands = data.split('|')command_type = commands[0]if command_type == "Heartbeat":self.clients[addr] = time.time()returnelif command_type == "Disconnect":if addr in self.clients:del self.clients[addr]print(f"Client {addr} disconnected")returnself.clients[addr] = time.time()if command_type == "CustomText":if len(commands) > 1:content = commands[1]self.broadcast_message(f"CustomText|{content}", exclude_addr=addr)self.sock.sendto("Message broadcasted".encode(), addr)except Exception as e:print(f"Message handling error: {e}")def cleanup_inactive_clients(self):while self.running:try:current_time = time.time()inactive_clients = [addr for addr, last_time in self.clients.items()if current_time - last_time > 30]for addr in inactive_clients:del self.clients[addr]print(f"Removed inactive client: {addr}")time.sleep(10)except Exception as e:print(f"Cleanup error: {e}")def broadcast_message(self, message, exclude_addr=None):for client_addr in list(self.clients.keys()):if client_addr != exclude_addr:try:self.sock.sendto(message.encode(), client_addr)except Exception as e:print(f"Broadcast error to {client_addr}: {e}")del self.clients[client_addr]def stop(self):self.running = Falseself.sock.close()print("Server stopped")if __name__ == "__main__":server = UDPServer()try:server.start()except KeyboardInterrupt:server.stop()
unity发送端UDPController.cs
using UnityEngine;
using System;
using System.Text;
using System.Net.Sockets;
using System.Net;
using UnityEngine.UI;public class UDPController : MonoBehaviour
{public InputField inputField;public Text messageLog;public Button sendButton;private UdpClient udp;private string serverIP = "0.0.0.0"; // 服务器IPprivate int serverPort = 7789; // 服务器端口private string pendingMessage = null; // 待处理的消息private float heartbeatInterval = 10f; // 心跳间隔private float nextHeartbeatTime = 0f;void Start(){InitializeUDP();if (sendButton != null){sendButton.onClick.AddListener(SendCustomText);}}private void InitializeUDP(){try{udp = new UdpClient();udp.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);udp.Client.Bind(new IPEndPoint(IPAddress.Any, 0));udp.Connect(IPAddress.Parse(serverIP), serverPort);LogMessage($"控制端初始化成功，本地端口: {((IPEndPoint)udp.Client.LocalEndPoint).Port}");udp.BeginReceive(new AsyncCallback(OnReceived), udp);}catch (Exception e){LogMessage($"初始化失败: {e.Message}");}}public void SendCustomText(){if (string.IsNullOrEmpty(inputField.text)) return;try{string message = $"CustomText|{inputField.text}";byte[] sendBytes = Encoding.UTF8.GetBytes(message);udp.Send(sendBytes, sendBytes.Length);LogMessage($"已发送: {inputField.text}");inputField.text = ""; // 清空输入框}catch (Exception e){LogMessage($"发送失败: {e.Message}");}}private void OnReceived(IAsyncResult result){try{UdpClient socket = result.AsyncState as UdpClient;IPEndPoint source = new IPEndPoint(IPAddress.Any, 0);byte[] message = socket.EndReceive(result, ref source);string receivedData = Encoding.UTF8.GetString(message);pendingMessage = receivedData;// 继续监听socket.BeginReceive(new AsyncCallback(OnReceived), socket);}catch (Exception e){Debug.LogError($"接收消息失败: {e.Message}");}}private void Update(){if (pendingMessage != null){LogMessage($"服务器响应: {pendingMessage}");pendingMessage = null;}// 发送心跳if (Time.time >= nextHeartbeatTime){SendHeartbeat();nextHeartbeatTime = Time.time + heartbeatInterval;}}private void SendHeartbeat(){try{string message = "Heartbeat|";byte[] sendBytes = Encoding.UTF8.GetBytes(message);udp.Send(sendBytes, sendBytes.Length);}catch (Exception e){Debug.LogError($"发送心跳失败: {e.Message}");}}private void LogMessage(string message){if (messageLog != null){messageLog.text += $"\n{message}";}Debug.Log(message);}void OnDestroy(){if (udp != null){try{string message = "Disconnect|";byte[] sendBytes = Encoding.UTF8.GetBytes(message);udp.Send(sendBytes, sendBytes.Length);}catch (Exception e){Debug.LogError($"发送断开消息失败: {e.Message}");}finally{udp.Close();udp.Dispose();}}}
}
unity接收端UDPReceiver.cs
using UnityEngine;
using System;
using System.Text;
using System.Net.Sockets;
using System.Net;
using UnityEngine.UI;
using UnityEngine.Events;[System.Serializable]
public class CustomTextEvent : UnityEvent<string> { }public class UDPReceiver : MonoBehaviour
{public Text messageLog;public CustomTextEvent onCustomTextReceived; // Unity事件，用于处理接收到的文本private UdpClient udp;private string serverIP = "0.0.0.0"; // 服务器IPprivate int serverPort = 7789; // 服务器端口private string pendingMessage = null; // 待处理的消息private string pendingContent = null; // 待处理的内容private float heartbeatInterval = 10f;private float nextHeartbeatTime = 0f;void Start(){InitializeUDP();if (onCustomTextReceived == null){onCustomTextReceived = new CustomTextEvent();}}private void InitializeUDP(){try{udp = new UdpClient();udp.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);udp.Client.Bind(new IPEndPoint(IPAddress.Any, 0));byte[] connectMessage = Encoding.UTF8.GetBytes("CustomText|Connected");udp.Send(connectMessage, connectMessage.Length, serverIP, serverPort);udp.BeginReceive(new AsyncCallback(OnReceived), udp);LogMessage($"接收端初始化成功，本地端口: {((IPEndPoint)udp.Client.LocalEndPoint).Port}");}catch (Exception e){LogMessage($"初始化失败: {e.Message}");}}private void OnReceived(IAsyncResult result){try{UdpClient socket = result.AsyncState as UdpClient;IPEndPoint source = new IPEndPoint(IPAddress.Any, 0);byte[] message = socket.EndReceive(result, ref source);string receivedData = Encoding.UTF8.GetString(message);pendingMessage = receivedData;socket.BeginReceive(new AsyncCallback(OnReceived), socket);}catch (Exception e){Debug.LogError($"接收消息失败: {e.Message}");}}private void Update(){if (pendingMessage != null){HandleMessage(pendingMessage);pendingMessage = null;}if (pendingContent != null){OnCustomTextReceived(pendingContent);pendingContent = null;}// 发送心跳if (Time.time >= nextHeartbeatTime){SendHeartbeat();nextHeartbeatTime = Time.time + heartbeatInterval;}}private void HandleMessage(string data){try{string[] parts = data.Split('|');if (parts.Length < 2) return;string messageType = parts[0];string content = parts[1];switch (messageType){case "CustomText":pendingContent = content;break;}}catch (Exception e){LogMessage($"处理消息时出错: {e.Message}");}}private void OnCustomTextReceived(string text){LogMessage($"收到文本: {text}");onCustomTextReceived?.Invoke(text); // 触发Unity事件}private void LogMessage(string message){if (messageLog != null){messageLog.text += $"\n{message}";}Debug.Log(message);}private void SendHeartbeat(){try{string message = "Heartbeat|";byte[] sendBytes = Encoding.UTF8.GetBytes(message);udp.Send(sendBytes, sendBytes.Length, serverIP, serverPort);}catch (Exception e){Debug.LogError($"发送心跳失败: {e.Message}");}}void OnDestroy(){if (udp != null){try{string message = "Disconnect|";byte[] sendBytes = Encoding.UTF8.GetBytes(message);udp.Send(sendBytes, sendBytes.Length, serverIP, serverPort);}catch (Exception e){Debug.LogError($"发送断开消息失败: {e.Message}");}finally{udp.Close();udp.Dispose();}}}
}
部署
宝塔面板–文件
创建项目文件夹
server.py上传(其他文件忽略，这是后来生成的)
需安装对应的python版本(3.10.14)
点击添加python项目。
项目路径选择刚才创建好的文件夹。
项目名称随意填。
运行文件选择目录内的server.py脚本
项目端口选择7789。(脚本里写的7789)
别忘了勾选放行端口！就是这个导致我后面调试了半小时…我怎么记得我勾选了呢？
python版本根据你开发的版本来。
框架选择python
由于这个demo不需要安装额外依赖，所以不填。
确认上述没问题后点击确定。
可以看到项目运行中
这时候还没结束，需要去开放安全组和对应的防火墙。
这台服务器是阿里云的，到ECS后台–安全组，添加入方向端口号7789，授权对象0.0.0.0
宝塔面板–安全这里也要检查下是否有7789的UDP协议的端口号！如果上面没勾选放行端口，这里就没有。
最后在本地客户端上进行验证，同时在服务器–设置–项目日志查看记录
调试命令
服务器上运行以下命令排查。
netstat -nulp | grep 7789检查端口是否在监听
firewall-cmd --list-ports检查服务器防火墙中的端口
用以下命令添加也可以，最好还是宝塔防火墙里直接开放也省事。
# 查看活动的防火墙区域
firewall-cmd --get-active-zones# 为docker区域添加UDP端口
firewall-cmd --zone=docker --add-port=7789/udp --permanent
firewall-cmd --reload# 验证端口是否添加成功
firewall-cmd --zone=docker --list-ports
写到最后
切记要检查ECS安全组、宝塔防火墙设置是否开放了端口号！(给自己提个醒)
