main.ts

import { app, BrowserWindow, ipcMain } from 'electron';
import { Eimer, EimerIpcMainTransport } from 'eimer';
import * as path from 'path';

let mainWindow: BrowserWindow;

// Set up main process node
const eimer = new Eimer('main');

// Set up counter state in main process
let counter = Math.round(Math.random() * 100);

// Handle increment/decrement RPC calls
eimer.registerRpcHandler('counter.increment', async () => {
    counter += 1;
    eimer.publish('counter.change', counter);
    return counter;
});

eimer.registerRpcHandler('counter.decrement', async () => {
    counter -= 1;
    eimer.publish('counter.change', counter);
    return counter;
});

eimer.registerRpcHandler('counter.get', async () => {
    console.log('counter', counter);
    return counter;
});

// Start the app
app.whenReady().then(() => {
    // Create main window
    mainWindow = new BrowserWindow({
        width: 1440,
        height: 600,
        webPreferences: {
            sandbox: true,
            preload: path.join(__dirname, 'preload.js')
        }
    });

    // connect eimer to preload/renderer via ipcMain
    eimer.connect(new EimerIpcMainTransport(ipcMain, mainWindow.webContents));

    // Load the renderer
    mainWindow.loadFile(path.join(__dirname, '../index.html'));
    mainWindow.webContents.openDevTools();

    app.on('window-all-closed', () => {
        if (process.platform !== 'darwin') {
            app.quit();
        }
    });
});