next.js/examples/with-electron/main/index.js

// Native
const { join } = require("path");
const { format } = require("url");

// Packages
const { BrowserWindow, app, ipcMain } = require("electron");
const isDev = require("electron-is-dev");
const prepareNext = require("electron-next");

// Prepare the renderer once the app is ready
app.on("ready", async () => {
  await prepareNext("./renderer");

  const mainWindow = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
      nodeIntegration: false,
      preload: join(__dirname, "preload.js"),
    },
  });

  const url = isDev
    ? "http://localhost:8000"
    : format({
        pathname: join(__dirname, "../renderer/out/index.html"),
        protocol: "file:",
        slashes: true,
      });

  mainWindow.loadURL(url);
});

// Quit the app once all windows are closed
app.on("window-all-closed", app.quit);

// listen the channel `message` and resend the received message to the renderer process
ipcMain.on("message", (event, message) => {
  event.sender.send("message", message);
});