How to build a website blocker using python

Hi guys

Many of us struggle to focus nowadays, easily distracted by Social media and some sites on the internet which dramatically affecting our productivity.

In this tutorial, you will learn and build your own website blocker to block certain selected sites that distract you during working hours.

Requirements

We are going to use the time and Datetime Module only which comes by default with the Python Standard Library therefore you don’t need to install anything.

How do we block sites?

Every operating system has a host file and it’s on this file where we are going to add a list of websites we want to block by redirecting them to 127.0.0.1 (localhost).

We will add website URLs to the host file and mapping them to the localhost thus preventing you from accessing the real site during working hours.

Instead of adding www.facebook.com we are going to add 127.0.0.1 www.facebook.com, therefore whenever a user tries to access the website during working hours will be directed to the localhost.

Therefore we need to add those sites to the host files during working hours and removing them immediately when it’s going home time.

if working_time:
  add mapped websites url to host file 
else:
  remove the website files from the host file 

Location of host file

Host file that we need to edit is stored on different path depending on the Operating system you’re using

For those in Linux

Linux_host = "/etc/hosts"

For those in window

Window_host = r"C:\Windows\System32\drivers\etc\hosts"

Building our Website Blocker

Importing modules & pre-configuring

import time
from datetime import datetime as dt
​
sites_to_block = [
    'www.facebook.com',  'facebook.com',  
    'www.youtube.com', 'youtube.com',
    'www.gmail.com', 'gmail.com'
]
​
Linux_host = '/etc/hosts'
Window_host = r"C:\Windows\System32\drivers\etc\hosts"
redirect = "127.0.0.1"

We then required to add the sites to be blocked during working hours and remove them when it is not, I  have made a simple function  just to do that as shown in the source code below

Note
If your own Window change the default_hoster to Window_host

import time
from datetime import datetime as dt
​
sites_to_block = [
    'www.facebook.com',  'facebook.com',  
    'www.youtube.com', 'youtube.com',
    'www.gmail.com', 'gmail.com'
]
​
Linux_host = '/etc/hosts'
MacOs_host = '/private/etc/hosts'
Window_host = r"C:\Windows\System32\drivers\etc\hosts"
default_hoster = Linux_host
redirect = "127.0.0.1"
​
def block_websites(start_hour , end_hour):
    while True:
        if dt(dt.now().year, dt.now().month, dt.now().day,start_hour)< dt.now() < dt(dt.now().year, dt.now().month, dt.now().day,end_hour): 
            print("Do the work ....")
            with open(default_hoster, 'r+') as hostfile:
                hosts = hostfile.read()
                for site in  sites_to_block:
                    if site not in hosts:
                       hostfile.write(redirect+' '+site+'\n')
        else:
            with open(default_hoster, 'r+') as hostfile:
                hosts = hostfile.readlines()
                hostfile.seek(0)
                for host in hosts:
                    if not any(site in host for site in sites_to_block):
                        hostfile.write(host)
                hostfile.truncate()
            print('Good Time')
        time.sleep(3)
​
if __name__ == '__main__':
    block_websites(9, 18)

The function receives two-parameter, One is the starting time on which for testing I set as 9 am and the ending time for a job which I initially set 18 but you can twist it whatever you want.

When you run the above code, It will do as we have said, you can try accessing sites you listed in sites_to_block it will redirect you to the localhost.

If you find it interesting, Don't be shy share it with your fellow tech nerds so as more can learn this trick

Kalebu Jordan
I am a Mechatronics engineer and professional Python Developer passionate about innovation, opensource and technical writing, Here I will be writing mostly on Python, DevOps, AI/ML and security
Dar es Salaam, Tanzania