SocketServer

SocketServer is a utility class for managing WebSocket channels using Socket.IO, with integrated JWT authentication and API key validation.

Installation

Ensure you have Node.js and npm installed. Then install the required packages:

`npm install socket-lemur`

Usage

Initialize the SocketServer instance and define custom event handlers for your application.

const { SocketServer } = require("socket-lemur");

// Port Definition
const PORT = process.env.PORT || 4000;

// SocketServer Definition
const server = new SocketServer<{ id: string }>({
  apikey: "api-key",
  secret: "jwt-secret",
  roomsEnabled: true,
});

// SocketServer Definition whit app express
import express from "express";
import { createServer } from "http";

const app = express();
const httpServer = createServer(app);
const server = new SocketServer<{ id: string }>(
  {
    apikey: "api-key",
    secret: "jwt-secret",
    roomsEnabled: true,
  },
  httpServer
);

const data = [
  { id: 1, name: "Pizza" },
  { id: 2, name: "Pasta" },
];

// Actions Definition
async function get() {
  return data;
}

async function add(product: { name: string }) {
  data.push({ id: data.length + 1, name: product.name });
  return data;
}

// Channels Definition
server.customChannel<{ name: string }>(
  "post/products",
  async (req, { emit, to, room }, error) => {
    try {
      if (!req.body.name) throw new Error("field name is required!.");
      const products = await add(req.body);

      // emit
      emit("custom response channel", products);
      to("custom response channel", products, room);
    } catch (err: any) {
      error(err?.message);
    }
  }
);

server.channel<any[]>("get/products", async function (_, res) {
  const products = await get();
  res(products);
});

server.channel<{ name: string }>(
  "post/products",
  async function (req, res) {
    const products = await add(req.body);
    res(products);
  },
  true
);

// Server run on port
server.listen(PORT, function () {
  console.log(`Server Run http://localhost:${PORT}`);
});

// On connection
server.connection({
  on: function () {
    console.log("onConnection");
  },
  off: function () {
    console.log("onDisconnect");
  },
});

// More event definitions can be added here

Constructor

new SocketServer<S>(settings?)

Creates a new instance of SocketServer.

const default: Partial<ServerOptions> = {
    cors: {
        origin: "*", // Configure CORS as needed
        methods: ["GET", "POST"],
        credentials: true,
    },
    allowEIO3: true
};

• apikey (optional): API key for validating requests.
• secret (optional): Secret key for JWT token validation.
• options (optional): Socket.IO server settings default.
• roomsEnabled (optional): Whether to enable room support false.

Methods

channel(name, onEvent, tokenRequire, roomSupport)

Establishes channel handling and defines event listeners for Socket.IO.

Parameters:

Initialize handling for a channel with optional room support.

• name: {string} - The name of the channel.
• onEvent: {onEvent} - Callback to handle incoming events.
• tokenRequire: {boolean} - Whether token authentication is required for events on this channel false.
• roomSupport: {boolean} - Whether room support is enabled for this channel this.roomsEnabled.

listen:

This method receives the same parameters or configuration from an http server.

• port: {number}.
• hostname: {string}.
• backlog: {number}.
• listeningListener: {function}.

connection:

The server's connection method receives an object with two properties on and off, on detects when a client connects and off when that client disconnects.

• on: {function} connection callback function.
• off: {function} disconnection callback function.

SocketClient

SocketClient class facilitates WebSocket communication with a server using Socket.IO.

Usage

Initialize SocketClient to connect to a WebSocket server and handle events.

const { SocketClient } = require("socket-lemur");

const PORT = 3030;
const url = `http://localhost:${PORT}`;

// Initialize SocketClient with api_key
const socket = new SocketClient(url, {
  apiKey: "api-key",
});
// Initialize SocketClient with api_key and token
const socket = new SocketClient(url, {
  apiKey: "api-key",
  token: "token",
});

function error(error) {
  console.error("Event error:", error);
}
function success(data) {
  console.error("Event success:", data);
}
// Connect to a WebSocket channel and define event handlers
const postProduct = socket.channel<any>("post/products", {
  onSuccess: success,
  onError: error,
  room: "post",
});

// Response custom channel
const postProduct = socket.channel<any>("post/products", {
  onSuccess: success,
  onError: error,
  successChannel: 'custom/products'
  room: "post",
});

const geProducts = socket.channel<any[]>("get/products", {
  onSuccess: success,
  onError: error,
});

geProducts.on(); // Adds the listener function to the end of the listeners array for the event named eventName.
geProducts.off(); // Removes the specified listener from the listener array for the event named eventName.
geProducts.emit();
postProduct.emit(
  {
    data: { name: "coffe" },
    params: { room: "post" },
  },
  "tokent"
);

Constructor

new SocketClient(serverUrl, apiKey, authToken?)

Creates an instance of SocketClient to connect to a WebSocket server.

interface Security {
  apiKey?: string;
  token?: string;
}

• serverUrl: {string} - The URL of the WebSocket server.
• security: {Security} - Optional security options {apiKey, token}.
• onError: {OnErrorCallback} - Optional callback to handle errors.

Methods

channel(name, opts: LemurOpts): EmitEvent

Connects to a WebSocket channel and sets up callbacks for error and success events.

declare type LemurOpts<T> = {
  onSuccess: OnSuccessCallback<T>;
  onError?: OnErrorCallback;
  room?: string;
};

• name: {string} - The name of the channel to connect to.
• opts: {LemurOpts} - The options for the channel, including success and error callbacks, and an optional room.

The channel method returns an object with multiple actions

• emit: {(data?, token?) => void} - Emits an event to the channel with optional data and token.
• off: {() =>void} - Removes the event listeners for the channel.
• on: {() =>void} - Event listeners for the channel.

Annotations

To implement SocketClient in vite you must configure this plugin to use Buffer.

• npm i -D vite-plugin-node-polyfills

import { defineConfig } from "vite";
import { nodePolyfills } from "vite-plugin-node-polyfills";

export default defineConfig({
  plugins: [
    // ... other plugin
    nodePolyfills(),
  ],
});