khamba/dist/functions/udpServer.js

A cli tool for sharing files through local network.

import dgram from 'dgram';
import { useEffect } from 'react';
import useBroadcast from '../functions/broadcast.js';
import { addDiscoveredPeer } from '../stores/peersStore.js';
import chalk from 'chalk';
import { log, logError } from '../functions/log.js';
export const useUdpServer = (MY_ID, NAME, BROADCAST_ADDR, MY_IP, UDP_PORT, HTTP_PORT) => {
    const { broadcast } = useBroadcast();
    useEffect(() => {
        const server = dgram.createSocket({
            type: 'udp4',
            reuseAddr: true,
        });
        server.bind({
            port: UDP_PORT,
            address: '0.0.0.0',
            exclusive: false,
        });
        const msg = {
            method: 'SELF',
            name: NAME,
            id: MY_ID,
            ip: MY_IP,
            httpPort: HTTP_PORT,
            isBroadcast: true,
        };
        const initialBroadcast = () => {
            broadcast(server, BROADCAST_ADDR, UDP_PORT, JSON.stringify(msg));
        };
        server.on('listening', function () {
            const address = server.address();
            log(`Listening on ${address.address}:${address.port}`);
            server.setBroadcast(true);
            initialBroadcast();
        });
        server.on('message', (receivedMsg, rinfo) => {
            const data = JSON.parse(receivedMsg?.toString());
            if (data.id == MY_ID) {
                return;
            }
            // log('DATA:', data);
            // ! DEBUGGING...
            if (data?.isBroadcast) {
                log(`${chalk.bgYellow('<-- Broadcasted From:')} ${chalk.underline(data.name)}: ${data.id}`);
            }
            else {
                log(`${chalk.bgCyan('<-- Received From:')} ${chalk.underline(data.name)}: ${data.id}`);
            }
            if (data?.method == 'SELF') {
                const isAlreadyAdded = !addDiscoveredPeer({
                    id: data.id,
                    ip: rinfo.address,
                    name: data.name,
                    httpPort: data?.httpPort,
                });
                if (!isAlreadyAdded || data?.isBroadcast) {
                    const message = JSON.stringify({
                        ...msg,
                        isBroadcast: false,
                    });
                    server.send(message, rinfo.port, rinfo.address);
                }
            }
        });
        server.on('error', err => {
            logError(`server error:\n${err.stack}`);
            server.close();
        });
        return () => {
            server.close();
        };
    }, []);
};