Using Python's os Module

Using the best practice, Test-Driven Development, first write a test that will check to make sure your result matches what is wanted. There is a # test section for your code. The test_printer_config.ini file contains the result you should check against. Remember streams and file i/o to read the resulting file, the test file, and assert they are equal.

After you have written the test, run python write_config.py.

This should result in an AssertionError which you will fix in the next step.

import configparser
import os

# data to be used
data_list = [
    ["author", "title", "pages", "due_date", "genre", "isbn"],
    ["Thompson, Keith", "Oh Python! My Python!", 1200, "2020-11-15", "biography", "000-1-000000-00-1"],
    ["Fritts, Larry", "Fun with Django", 150, "2020-06-23", "satire", "00-2-000000-00-2"]
]

novel_text = "Numquam labore labore tempora. Dolore dolorem quisquam aliquam eius dolor non ipsum. Dolorem est velit tempora quaerat. Est magnam porro voluptatem dolore. Adipisci voluptatem consectetur dolore voluptatem voluptatem neque. Adipisci non modi quiquia etincidunt quisquam. Etincidunt consectetur dolore ut. Quaerat ut adipisci sit aliquam quisquam ut. Voluptatem labore porro porro.\n\nPorro modi numquam non sed dolor. Consectetur dolor adipisci quaerat aliquam adipisci. Etincidunt porro modi dolor neque numquam magnam neque. Ipsum consectetur ut eius ut. Dolor ut modi non est tempora labore sit.\n\nEtincidunt voluptatem quaerat consectetur sed est etincidunt ipsum. Ut adipisci numquam etincidunt porro porro. Dolore eius modi aliquam. Velit amet sed quaerat etincidunt est. Ut consectetur modi ipsum sed aliquam. Amet tempora quiquia eius voluptatem aliquam dolore ut. Etincidunt dolor non voluptatem eius sed non adipisci."

# instantiate the configparser object
config = configparser.ConfigParser()

# add default section
config["DEFAULT"] = {
    "pub_house": "Atlantic Publishing",
    "number_of_books": '2'
}

# add first book
config["book1"] = {
    "author": data_list[1][0],
    "title": data_list[1][1],
    "genre": data_list[1][4],
    "text": novel_text
}

# add second book
config["book2"] = {
    "author": data_list[2][0],
    "title": data_list[2][1],
    "genre": data_list[2][4],
    "text": novel_text
}

# print to file
with open("printer_config.ini", "w") as f:
    config.write(f)

# test
# student input here
with open("printer_config.ini", "r") as f:
    config_text = f.read()

with open("test_printer_config.ini", "r") as f:
    expected_text = f.read()

assert config_text == expected_text, f"Expected: {expected_text}\n\nGot: {config_text}"

The DEFAULT section of printer_config.ini should look like this:

[DEFAULT]
pub_house = Atlantic Publishing
pub_house_address = 321 Publishers Way, Fargo, ND
pub_house_phone = 555-555-5555

The environment variables are:

• PUB_HOUSE = "Atlantic Publishing"
• PUB_HOUSE_ADDRESS = "321 Publishers Way, Fargo, ND"
• PUB_HOUSE_PHONE = "555-555-5555"

Change the code in write_config.py to update the default section.

import configparser
import os

# data to be used
data_list = [
    ["author", "title", "pages", "due_date", "genre", "isbn"],
    ["Thompson, Keith", "Oh Python! My Python!", 1200, "2020-11-15", "biography", "000-1-000000-00-1"],
    ["Fritts, Larry", "Fun with Django", 150, "2020-06-23", "satire", "00-2-000000-00-2"]
]

novel_text = "Numquam labore labore tempora. Dolore dolorem quisquam aliquam eius dolor non ipsum. Dolorem est velit tempora quaerat. Est magnam porro voluptatem dolore. Adipisci voluptatem consectetur dolore voluptatem voluptatem neque. Adipisci non modi quiquia etincidunt quisquam. Etincidunt consectetur dolore ut. Quaerat ut adipisci sit aliquam quisquam ut. Voluptatem labore porro porro.\n\nPorro modi numquam non sed dolor. Consectetur dolor adipisci quaerat aliquam adipisci. Etincidunt porro modi dolor neque numquam magnam neque. Ipsum consectetur ut eius ut. Dolor ut modi non est tempora labore sit.\n\nEtincidunt voluptatem quaerat consectetur sed est etincidunt ipsum. Ut adipisci numquam etincidunt porro porro. Dolore eius modi aliquam. Velit amet sed quaerat etincidunt est. Ut consectetur modi ipsum sed aliquam. Amet tempora quiquia eius voluptatem aliquam dolore ut. Etincidunt dolor non voluptatem eius sed non adipisci."

# instantiate the configparser object
config = configparser.ConfigParser()

# add default section
config["DEFAULT"] = {
    "pub_house": os.getenv("PUB_HOUSE"),
    "pub_house_address": os.getenv("PUB_HOUSE_ADDRESS"),
    "pub_house_phone": os.getenv("PUB_HOUSE_PHONE")
}

# add first book
config["book1"] = {
    "author": data_list[1][0],
    "title": data_list[1][1],
    "genre": data_list[1][4],
    "text": novel_text
}

# add second book
config["book2"] = {
    "author": data_list[2][0],
    "title": data_list[2][1],
    "genre": data_list[2][4],
    "text": novel_text
}

# print to file
with open("printer_config.ini", "w") as f:
    config.write(f)

# test
with open("printer_config.ini", "r") as f:
    config_text = f.read()

with open("test_printer_config.ini", "r") as f:
    expected_text = f.read()

assert config_text == expected_text

Run python write_config.py.

Congrats! You have successfully accessed environment variables using Python's os module.