Programming Sockets in Python

| programming | python |

EDIT: I am sorry for derping out of control. When I initially published this post it was called “Programming Web Sockets in Python”, this is just flat out wrong. What we are making here is just a regular socket. Web Sockets and regular sockets are similar but are certainly not the same thing. I hope you will still find this useful! Sockets are pretty much the basis of how applications work on the Internet. Python makes it super easy to get started programming sockets. In this brief introduction we will create a simple server that greets the user when it receives incoming requests from the client application. Due to my recent obsession with Linux Containers we will also be implementing this inside of two containers. Containers make it really simple to simulate a network because you can create additional hosts in seconds.

Creating your Containers

I am running Ubuntu 14.04. So creating two additional containers can be achieved by running the following as the root user. 
lxc-create -t download -n pyServer 


  Choose ubuntu, trusty, amd64 when prompted
  
    
      
      
    
  




  Then clone the first container
  
    
      
      
    
  



lxc-clone -o pyServer -n pyClient

Running the Server

Now that we have created our containers lets jump into our server container and fire up our simple server application. We can start up the container by issuing the following command as root: lxc-start -n pyServer -d, this will start the container as a daemon. Let’s go ahead and get into by attaching the container. I like to do this inside of screen so that we can easily get in and out of the container. Create a screen session screen -dRR pyServer and once inside the screen attach the container lxc-attach -n pyServer Once we are inside the container we need to install python and launch our simple server. 
apt-get install python vim pyServer.py
Inside of vim (or your favorite text editor) we need to enter the following simple python code. 
from socket import *  

serverPort = 12000

serverSocket = socket(AF_INET, SOCK_DGRAM)

serverSocket.bind((’’, serverPort))

print “The server is ready to rock and roll!"


while 1:  

    name, clientAddress = serverSocket.recvfrom(2048)  

    response = “Hello “ + str(name) + ”! You are really good at socket programming”  

    serverSocket.sendto(response, clientAddress)

The code should be pretty straightforward. We are creating a new serverSocket that is bound to port 12000. When it receives requests (which include a name) it responds with an encouraging message. Fire up this server by running python pyServer.py if all goes well you should see a message that states This server is ready to rock and roll! Exit the container (and the screen session) by pressing Ctrl+a and Ctrl+d

Running the Client

Now that we have our server up and running, lets get our client working as well. Before we move forward, lets grab the IP address of our server container because we will need it soon. You can get the IP by runninglxc-ls --fancy. Launch the client container, attach it in screen, and install python in the same way that we did previously. 
lxc-start -n pyClient -d screen -dRR pyClient 
lxc-attach -n pyClient 
apt-get install python 
vim pyClient.py
In vim, lets create the pyClient.py program by entering the following code. 
from socket import *  

# Replace the IP address in serverName with the IP of your container that you grabbed previously.


serverName = ‘10.0.3.211’
serverPort = 12000
clientSocket = socket(AF_INET, SOCK_DGRAM)

name = raw_input(‘Please enter your name:’)

clientSocket.sendto(name, (serverName, serverPort))


response, serverAddress = clientSocket.recvfrom(2048)
print response
clientSocket.close()

This code is also pretty straightforward. It asks the user for their name, sends it to the server, and prints the response. You can try this out now! Save the file and execute your python program by runningpython pyClient.py. After entering your name and pressing enter you should see a response from your server with the encouraging message. This was a pretty trivial exercise, but we can quickly see that we can expand upon this basic code to create much more interesting and complex applications. We can also leverage the power and simplicity of LXC to create a simulated large network for distributed applications.

Thank you for reading! Share your thoughts with me on bluesky, mastodon, or via email.

Check out some more stuff to read down below.

Most popular posts this month

Recent Favorite Blog Posts

This is a collection of the last 8 posts that I bookmarked.

Articles from blogs I follow around the net

People fall in love with all kinds of things including AI chatbots

OpenAI recently released a new version of its ChatGPT artificial-intelligence engine, called GPT-5. Normally, I wouldn't choose to write about the latest iteration of a product that is in its fifth generation, especially since GPT-5 doesn't seem r…

via The Torment Nexus August 14, 2025

Theatre Review: Being Mr Wickham ★★★★★

Mr Wickham is ready to set the record straight. Celebrating the 250th anniversary of Jane Austen’s birth, Adrian Lukis, who starred in the renowned BBC TV adaptation of Pride and Prejudice, returns to the role of Mr Wickham. Join Pride and Prejudice’s mo…

via Terence Eden’s Blog August 14, 2025

The Library

Rose’s favorite daddy-daughter dates are at the libraries. We try to go once or twice a week. To play. To build in the sensory room. To look at all the Amiibos near the front entrance. To use the elevator. To walk around. To observe. To think. To have a…

via nashp.com August 14, 2025

Generated by openring