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Automation & scripting

CLI tools, scheduled jobs, filesystem tasks, and glue scripts that save time.

4 matches

How to Build a Simple argparse CLI in Python

Build a beginner-friendly command-line tool with argparse that greets a user, with optional greeting text and uppercase output.

argparse cli command-line

Python

import argparse

def greet(name, greeting="Hello", uppercase=False):
    message = f"{greeting}, {name}!"
    if uppercase:
        message = message.upper()
    return message

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Simple CLI greeting tool")
    parser.add_argument("name", help=…

13 0 Open

Automation & scripting easy

How to Build an argparse CLI That Filters File Lines by Keyword in Python

This Python script is a command-line tool built with argparse that reads a text file and prints only the lines that contain (or don't contain) a given keyword.

argparse cli filter

Python

import argparse
import sys

def main():
    parser = argparse.ArgumentParser(description="Filter lines from a file by keyword.")
    parser.add_argument("input", type=str, help="File to read")
    parser.add_argument("keyword", type=str, help="Keyword to filter lines")
    parser.add_argument("--contains", action="sto…

14 0 Open

Automation & scripting easy

How to Parse Terraform Plan Output in Python

Parse mock Terraform plan output text into structured add, change, and destroy lists using Python.

terraform parsing automation

Python

import json
from typing import Dict, List

def parse_terraform_plan_output(plan_output_text: str) -> Dict[str, List[str]]:
    """
    Parses a mock Terraform plan output text into a structured dictionary.
    """
    parsed: Dict[str, List[str]] = {"add": [], "change": [], "destroy": []}

    for line in plan_output_…

11 0 Open

Automation & scripting easy

Pin Python package versions in requirements.txt

Pin package versions in requirements.txt-style text by adding ==version when no specifier is present, while preserving existing version constraints and comments.

requirements automation versions

Python

import re
from pathlib import Path


def pin_versions(requirements_text: str) -> str:
    """
    Pin package versions in requirements.txt-style text.
    Adds ==version if no version specifier is present.
    Keeps existing specifiers (>=, <=, ~=, etc.) unchanged.
    """
    lines = requirements_text.strip().splitli…

14 0 Open

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