Part 1: Child process as prelude to interprocess communication

The child process as prelude to interprocess communication

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What the hell are you talking about??
Not EMScripten, not any R&D cool finding, just some observation of using the Electron app pattern.

Electron is a cross-platform framework that glues system and browser via interprocess communications; and developed by Github (major thanks!).

(Oh yeah, it uses Javascript.. That is pretty cool.)

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EE: Electron boiler, meet Express boiler

'use strict';

const electron = require('electron');
const app = electron.app;
const BrowserWindow = electron.BrowserWindow;
const url = 'http://127.0.0.1:1987';

let mainWindow, child;

function windowRouter(_route) {
  return url + '/' + (_route || '');
}

function renderWindow() {
  mainWindow = new BrowserWindow({width: 800, height: 600});
  mainWindow.loadURL(windowRouter());
  // default to inspector mode in Chromium
  mainWindow.webContents.openDevTools();
  mainWindow.on('closed', function() {
    mainWindow = null;
  });
}

function createWindow () {
  renderWindow();
  let exec = require('child_process').exec;
  child = exec('node ./server.js');
  child.stdout.on('data', function(data) {
      console.log('stdout: ' + data);
  });
  child.stderr.on('data', function(data) {
      console.log('stdout: ' + data);
  });
  child.on('close', function(code) {
      console.log('closing code: ' + code);
      child.kill();
  });
}

app.on('ready', createWindow);

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

app.on('activate', function () {
  if (mainWindow === null) {
    createWindow();
  }
});

main.js

#!/usr/bin/env node
var express = require('express');
var app = module.exports = express();
var server = require('http').createServer(app);
var bodyParser = require('body-parser');
app.set('trust proxy', true);
app.use(bodyParser.json({limit: '50mb'}));
app.use(bodyParser.urlencoded({limit: '50mb', extended: true}));
app.use(require('cookie-parser')());

app.get('/', function(req, res) {
  console.log('GET /');
  res.send('<h1>foo lala</h1>');
})

var port = 1987;
var ipaddr = '127.0.0.1';
server.listen(port, ipaddr, function() {
  console.log('Express server listening on port ' + server.address().port + ' at ' + server.address().address);
});

server.js

npm start

> electron-quick-start@1.0.0 start /var/www/electron-quick-start
> electron main.js

stdout: Express server listening on port 1987 at 127.0.0.1

stdout: GET /

terminal

browser

The JS above was near identical, and the HTML was identical, to Electron's boilerplate, and package.json required modifying the additional packages. It's a good place to start!