UUID String Generator Python Coding Activity

June 29, 2022

In this activity, you will generate a universally unique ID (UUID) string using functions and module imports.

Starter file

# @TODO: Your code here

Instructions

Import the random and string modules.
Create a function that returns a universally unique ID (UUID).
- The function should accept a parameter for UUID length with the default size of 4.
- The function should accept a parameter for a string of characters.
- This string of characters will be the alphabet used to generate the UUID.
- For example, if we pass 'abcdef', the UUID can only consist of the letters ‘abcdef’.
- The length and characters parameters should be optional and have default values.
Define a default character alphabet using the constants provided by the string module.
To select random characters from the alphabet for your UUID, use one of the functions available for sequence selection in the random module.
Complete the test function to generate a variety of UUIDs and print them to the console.

Hints

Define a default character alphabet that combines ASCII letters with digits.
The random module has a function for making a random choice from an array. See the documentation for functions for sequences.
The code for the UUID function should create a list, append length random characters to the list, and then return the result of using join to create a string from the list.
See Stack Overflow for more info on UUIDs.

Solution

# -*- coding: UTF-8 -*-
"""UUID Generator.

This module allows us to generate a universally unique identifier (UUID)
with a custom length and character set.

"""

# Use import to access code from other modules.
import string
import random


# Use default parameters in our function declaration to allow us to change the length and characters
def generate_uuid(length=4, characters=string.ascii_letters + string.digits):
    """Generate a string of random characters.

    Args:
        length (int, optional): The length of the UUID to generate.
        characters (string, optional): The character set used to build the UUID.

    Returns:
        string: A string representation of the generated UUID.
    """
    # Loop through a range defined by the length size
    # In each loop, make a random choice from our characters and append that to the uuid list
    uuid = []
    for _ in range(length):
        uuid.append(random.choice(characters))
    # Use join to convert the uuid list to a string
    return ''.join(uuid)


def test():
    """Run test code."""

    # Generate a uuid using default values
    uuid = generate_uuid()
    print("UUID using default values: {}".format(uuid))

    # Generate a uuid of length 16 using the default character set
    uuid16 = generate_uuid(length=16)
    print("UUID of length 16: {}".format(uuid16))

    # Generate a uuid of random numbers using the default length
    uuid_random_numbers = generate_uuid(characters=string.digits)
    print("UUID of only numbers: {}".format(uuid_random_numbers))

    # Generate a uuid consisting of only letters
    uuid_random_letters = generate_uuid(characters=string.ascii_letters)
    print("UUID of only letters: {}".format(uuid_random_letters))

    # Generate a uuid of length 8 that includes punctuation in the character set
    uuid_with_punctuation = generate_uuid(
        length=8,
        characters=string.ascii_letters + string.digits + string.punctuation)
    print("UUID with punctuation: {}".format(uuid_with_punctuation))


# This conditional will execute the test function when running as a script.
# https://docs.python.org/3/library/__main__.html
if __name__ == '__main__':
    test()