dbgate/packages/electron/src/electron-wait-react.js

const net = require('net');
const port = 5000;

process.env.ELECTRON_START_URL = `http://localhost:${port}`;

const client = new net.Socket();

let startedElectron = false;
const tryConnection = () => client.connect({port: port}, () => {
        client.end();
        if(!startedElectron) {
            console.log('starting electron');
            startedElectron = true;
            const exec = require('child_process').exec;
            const electron = exec('yarn electron');
            electron.stdout.on("data", function(data) {
                console.log("stdout: " + data.toString());
            });
        }
    }
);

tryConnection();

client.on('error', (error) => {
    setTimeout(tryConnection, 1000);
});