Socket-starter NPM

Socket-Starter

🚨 Deprecated in favor of @jacekpietal/bouncer.js.

🚨 For upgrade guide refer to backwards-compatibility section of bouncer.js

Latest optional Clustered Express with Socket.IO and optional MongoDB Sticky-Session

What's this?

If you're only able to spawn one process and you'd like to have an express app with static content serving, and at the same time spawn X number of scalable microservices that use node and can connect websockets (socket.io for performance).

Common use case

Single process app server like a free heroku.com account or similar
Build a chat
Make a node + javascript games

Installation

It's hosted as an npm package so installation is of course as simple as:

yarn add socket-starter --save
# you will also need socket.io-client for frontend
# socket.io is auto-included

The application:

Node part you should do call the socketStarter (import socketStarter) function:

const socketStarter = require('socket-starter')

const server = createServer()

async function createServer() {
  return await socketStarter({
    plugins: {
      microService1: {
        initialize (io) => {},
        handshake(socket, data) => {
          console.log('This should be foobar:', data)
          socket.emit('messageFromMicroService1', 'payload1')
        }
      },
      microService2: {
        initialize (io) => {},
        handshake(socket, data) => {
          socket.emit('messageFromMicroService2', 'payload2')
        }
      }
      // ... any number of plugins
    },
    // Customization information below
    // Otherwise put static content inside root `static` directory
  })
}

Frontend can use the above backend in this manner (javascript part):

const io = require("socket.io-client");

const socket = io();

socket.on("connect", function () {
  ["messageFromMicroService1", "messageFromMicroService2"].forEach(
    (message) => {
      socket.on(message, (...args) => console.log(message, ...args));
    }
  );

  socket.emit("handshake:microService1", "foobar1");
  socket.emit("handshake:microService2");
});

Full Application (Chat) Example:

To run below example you can:

$ cd node_modules/socket-starter
$ yarn test

index.js of example chat minimum setup

const start = require("socket-starter");
const chat = require("socket-starter/lib/chat");

start({ plugins: { chat } });

See similar: example/index.js

This is how to create a vanilla simple chat with this socket starter it is already included @ socket-starter/lib/chat

const sillyname = require("sillyname");

// Socket Starter Format:
const plugin = {
  messages: [],
  initialize(io) {
    this.io = io;
  },
  handshake(socket, handshake) {
    this.socket = socket;
    this.socket.name = sillyname.randomAdjective();
    this.socket.on("sent", (data) => panda.call(this, "sent", data, true));
    this.socket.on("disconnect", (data) =>
      panda.call(this, "left", data, true)
    );
    this.socket.emit("messages", { messages: this.messages, handshake });
    panda.call(this, "joined", handshake, true);
  },
};

function panda(action, data, push = false) {
  const name = this.socket.name;
  this.io.emit(action, { name, data });
  if (push) {
    this.messages.push({ name, action, data });
    console.log(`🐼 ${name} ${action} ${JSON.stringify(data, null, 2)}`);
  }
}

module.exports = plugin;

/* MUCH WOW SO EASY */

You can provide the factory function with config key, which otherwise defaults to below configuration:

const cluster = require("cluster");

module.exports = {
  isMaster: cluster.isMaster,
  port: process.env.PORT || 8080,
  totalWorkers: process.env.WEB_CONCURRENCY || 1,
  socket: {
    origins: "*:*",
    connectionMessage: "sticky-session:connection",
  },
  sessionParams: {
    key: "socket-starter",
    secret: "TheCakeIsALie",
    resave: true,
    saveUninitialized: true,
  },
  mongoStore: {
    url: process.env.MONGODB_URI || "mongodb://localhost:27017/",
    collection: "sessions",
  },
  static: {
    directories: ["static"],
  },
};

see config.js

To see complimentary RAW frontend of above chat (index.html - working)

see example/static/index.html

Configuration/Customization

this is the app's configuration, see that falls back if not supplied with socket-starter/config.js

Config can also have optional express app instance as config.app = express()
Config can also have optional server instance as config.server or it will listen on config.server = config.app.listen()

Also Check out socket-starter/lib/app for more information about app instance...

Advanced

You can further extend the express application by providing the app or server params. If they are not provided, they default to below:

const createApp = require("socket-starter/lib/app");

if (!config.app) config.app = await createApp(config);
if (!config.server) config.server = config.app.listen();

see socket-starter/lib/app

So you might supply your own app (express) / server instance or not listen on it immediately...