Book Image

Socket.IO Cookbook

By : Tyson Cadenhead
Book Image

Socket.IO Cookbook

By: Tyson Cadenhead

Overview of this book

Socket.IO is a JavaScript library that provides you with the ability to implement real-time analytics, binary streaming, instant messaging, and document collaboration. It has two parts: a client-side library that runs in the browser, and a server-side library for node.js. Socket.IO is event-driven and primarily uses the WebSocket protocol that allows us to emit data bi-directionally from the server and the client. Socket.IO This book is a complete resource, covering topics from webSocket security to scaling the server-side of a Socket.IO application and everything in between. This book will provide real-world examples of how secure bi-directional, full-duplex connections that can be created using Socket.IO for different environments. It will also explain how the connection vulnerabilities can be resolved for large numbers of users and huge amounts of data/messages. By the end of the book, you will be a competent Socket.IO developer. With the help of the examples and real-world solutions,you will learn to create fast, scalable, and dynamic real-time apps by creating efficient messaging systems between the server side and the client side using Socket.IO.
Table of Contents (15 chapters)
Socket.IO Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Uploading an image to the filesystem


With Socket.IO, we can send files to our server over WebSockets instead of using an http POST request. Socket.IO allows us to upload files in real time and display the uploaded images as needed.

In this recipe, we will use Socket.IO to upload a file to our local filesystem and then send a message to the client to display the image when it is done uploading.

Getting ready…

For this recipe, we will use the built-in Node fs module to upload our images.

We will upload files to our filesystem, so make sure that you create a folder called tmp in the root of your project.

How to do it…

To upload an image to the filesystem with Socket.IO, follow these steps:

  1. First, we will need to create our server.js file. This file will be responsible for listening for new upload-image messages and uploading the file that is passed with the arguments:

    var express = require('express'),
    app = express(),
    http = require('http'),
    socketIO = require('socket.io'),
    fs = require('fs'),
    path...