Making automatic module installer in Python

Prerequisites: 

• urllib
• subprocess

Many times the task of installing a module not already available in built-in Python can seem frustrating. This article focuses on removing the task of opening command-line interface and type the pip install module name to download some python modules. In this article, we will try to automate this process.

Approach:

• Importing subprocess module to simulate command line using python
• Importing urllib.request for implementing internet checking facility.
• Input module name using input() function and initialize module_name variable.
• Send module name to the main function.
• In the main function, we first update our pip version directly through python for the smooth functioning of our app.
• In the next line p= subprocess.run(‘pip3 install ‘+module_name) we write pip3 install module_name virtually into the command line.
• Based on the combination of return code(p) of the above statement and return value of connect() function we can assume things mentioned below.

Return Code(P)	Connect Function	Result
1	False	Internet Off
1	True	Internet is On but some other problem occurred
0	True	Module Installed Successfully

• Based on the above table we can give the desired output.

Function used:

The connect() function is used for the following purposes:

1. To check whether internet is on or off.
2. Reach a specific URL using urllib.request.urlopen(host) command.
   • If reached successfully, return True
   • Else if not reached i.e internet is off, return false.

Given below is the implementation to achieve our functionality using the above approach.

Example:

Python3

# importing subprocess module
import subprocess

# importing urllib.requests for internet checking functions
import urllib.request

# initializing host to gfg.
def connect(host='https://www.geeksforgeeks.org/'):

    # trying to open gfg
    try:
        urllib.request.urlopen(host)
        return True

    # trying to catch exception when internet is not ON.
    except:
        return False


def main(module_name):

    # updating pip to latest version
    subprocess.run('python -m pip install --upgrade pip')

    # commanding terminal to pip install
    p = subprocess.run('pip3 install '+module_name)

    # internet off
    if(p.returncode == 1 and connect() == False):
        print("error!! occurred check\nInternet conection")

    # Every thing worked fine
    elif(p.returncode == 0):
        print("It worked", module_name, " is installed")

    # Name of module wrong
    elif(p.returncode == 1 and connect() == True):
        print("error!! occurred check\nName of module")


module_name = input("Enter the module name: ")
main(module_name)

Output: