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UDPServer¶

Inherits: RefCounted < Object

Helper class to implement a UDP server.

Description¶

A simple server that opens a UDP socket and returns connected PacketPeerUDP upon receiving new packets. See also PacketPeerUDP.connect_to_host.

After starting the server (listen), you will need to poll it at regular intervals (e.g. inside Node._process) for it to process new packets, delivering them to the appropriate PacketPeerUDP, and taking new connections.

Below a small example of how it can be used:

# server_node.gd
class_name ServerNode
extends Node

var server := UDPServer.new()
var peers = []

func _ready():
    server.listen(4242)

func _process(delta):
    server.poll() # Important!
    if server.is_connection_available():
        var peer: PacketPeerUDP = server.take_connection()
        var packet = peer.get_packet()
        print("Accepted peer: %s:%s" % [peer.get_packet_ip(), peer.get_packet_port()])
        print("Received data: %s" % [packet.get_string_from_utf8()])
        # Reply so it knows we received the message.
        peer.put_packet(packet)
        # Keep a reference so we can keep contacting the remote peer.
        peers.append(peer)

    for i in range(0, peers.size()):
        pass # Do something with the connected peers.

// ServerNode.cs
using Godot;
using System.Collections.Generic;

public partial class ServerNode : Node
{
    private UdpServer _server = new UdpServer();
    private List<PacketPeerUdp> _peers  = new List<PacketPeerUdp>();

    public override void _Ready()
    {
        _server.Listen(4242);
    }

    public override void _Process(double delta)
    {
        _server.Poll(); // Important!
        if (_server.IsConnectionAvailable())
        {
            PacketPeerUdp peer = _server.TakeConnection();
            byte[] packet = peer.GetPacket();
            GD.Print($"Accepted Peer: {peer.GetPacketIP()}:{peer.GetPacketPort()}");
            GD.Print($"Received Data: {packet.GetStringFromUtf8()}");
            // Reply so it knows we received the message.
            peer.PutPacket(packet);
            // Keep a reference so we can keep contacting the remote peer.
            _peers.Add(peer);
        }
        foreach (var peer in _peers)
        {
            // Do something with the peers.
        }
    }
}

# client_node.gd
class_name ClientNode
extends Node

var udp := PacketPeerUDP.new()
var connected = false

func _ready():
    udp.connect_to_host("127.0.0.1", 4242)

func _process(delta):
    if !connected:
        # Try to contact server
        udp.put_packet("The answer is... 42!".to_utf8_buffer())
    if udp.get_available_packet_count() > 0:
        print("Connected: %s" % udp.get_packet().get_string_from_utf8())
        connected = true

// ClientNode.cs
using Godot;

public partial class ClientNode : Node
{
    private PacketPeerUdp _udp = 