Communicating over sockets

One way to look at a socket is as a special file. Like a file, it's a readable and data container. On some operating systems, network sockets are literally a special type of file whereas, on others, the implementation is more abstract.

At any rate, the concept of a socket has changed our lives because it allows machines to communicate and to coordinate I/O across a network. Sockets are the backbone of distributed computing.

In this recipe, we'll build a TCP client and server.

Getting ready

Let's create two files, client.js and server.js, and open them in our favorite editor.

How to do it...

First, we'll create our server.

In server.js, let's write the following:

const net = require('net') 

net.createServer((socket) => { 
  console.log('-> client connected') 
  socket.on('data', name => { 
    socket.write(`Hi ${name}!`) 
  }) 
  socket.on('close', () => { 
    console.log('-> client disconnected') 
  }) 
}).listen(1337, 'localhost') 

Now for the client...