Error [ERR_SOCKET_DGRAM_IS_CONNECTED]: Already connected

[xxAROX]

Details

My client will not reconnect

Node.js version

v16.13.0

Example code

const web_socket = dgram.createSocket("udp4");
web_socket.connected = false;

web_socket.on("connect", async () => {
	console.log("Connected to socket");
	web_socket.connected = true;
	web_socket.close(); //for test, because the first connect works
});
web_socket.on("close", async () => {
	console.log("Closed connection");
	web_socket.connected = false;
	setTimeout(() => reconnectToSocket(), 1000 * 10);
});

const connectToSocket = (address, port) => {
	web_socket.last_address = address;
	web_socket.last_port = port;
	if (!web_socket.connected) {
		web_socket.connect(port ?? 16, address ?? "localhost");
	}
}
const reconnectToSocket = () => {
	console.log("RECONNECTING");
	console.log(web_socket.connected); //is false rn
	if (web_socket.connected) {
		web_socket.disconnect();
		web_socket.close();
	} else {
		try {
			web_socket.connect(web_socket.last_port ?? 16, web_socket.last_address ?? "localhost");
		} catch (e) {
			console.error(e);
		}
	}
}

connectToSocket("IP", PORT);

Operating system

win 10

Scope

code

Module and version

dgram

Result

Connected to socket
Closed connection
RECONNECTING
false
Error [ERR_SOCKET_DGRAM_IS_CONNECTED]: Already connected

[xxAROX]

What i trying to do is a reconnect loop

[xxAROX]

But if i try to send a packet it thow an error, Error [ERR_SOCKET_DGRAM_NOT_RUNNING]: Not running. So its not connected and also not running

[Trott]

@xxAROX I'm not sure exactly what you're trying to do, but if it helps, this code works:

const dgram = require('dgram');

const web_socket = dgram.createSocket("udp4");

web_socket.on("connect", async (err) => {
	console.log("Connected to socket");
	web_socket.disconnect();
	setTimeout(() => reconnectToSocket(), 1000 * 10);
});

const connectToSocket = (address, port) => {
	web_socket.last_address = address;
	web_socket.last_port = port;
	if (!web_socket.connected) {
		web_socket.connect(port ?? 16, address ?? "localhost");
	}
}
const reconnectToSocket = () => {
	console.log("RECONNECTING");
	try {
		web_socket.connect(web_socket.last_port ?? 16, web_socket.last_address ?? "localhost");
	} catch (e) {
		console.error(e);
	}
}

connectToSocket();

I think there's some confusion about what connect() and disconnect() do. They don't establish a network connection. (UDP is connectionless!) They associate your local socket with a remote address/port. They are a relatively recent addition to the API (added in Node.js 12.x) and I imagine most use cases don't need them. Instead of using connect(), a client can call send() with the address and port:

client.send(message, 41234, 'localhost', (err) => {
  client.close();
});

The documentation could probably be improved. @marsonya is looking into doing that.

[xxAROX]

ahh okay thank you, that works

[xxAROX]

Error [ERR_SOCKET_DGRAM_NOT_RUNNING]: Not running
    at new NodeError (node:internal/errors:371:5)
    at healthCheck (node:dgram:909:11)
    at Socket.send (node:dgram:643:3)

[xxAROX]

ahh, i got this

[xxAROX]

but first message was received from server

[xxAROX]

@Trott

[Trott]

@Trott

I'm sorry. I don't understand what you're asking. Perhaps you can provide some code and explain what's not working the way you expect?

[xxAROX]

ahh nvm, my issue