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CLI Command

shell-command.sh is a Bash script template for writing a single-file command-line interface (CLI) scripts. It's designed to be a single-file script without relying on any external packages, making it a self-contained program.

Below are some of its main features:

  1. Error Handling: Implements set -euo pipefail to prevent the script from continuing execution in case of errors, uninitialized variables, or failed commands, enhancing reliability.

Debug Mode: Controlled by the SCRIPT_DEBUG environment variable. When set to 1, the script runs in debug mode, providing verbose output to assist with debugging.

  • Utility Functions for User Interaction:

    • ask: Gathers input from the user with an option to specify a default value.
    • ask_yesno: Simplifies collecting yes/no responses from the user, incorporating default responses and input normalization.

  • Conditional Execution Based on User Confirmation: Features a check to confirm whether the user wishes to proceed with the operation, allowing for an early exit if desired.

  • Structured Script Design: Encapsulates the main logic within a main function, promoting code organization and readability. This structure also ensures that the script's main functionality is executed only when the script is not being sourced into another shell script.

Overall, this template offers a robust starting point for developing your own Shell CLI scripts.

Getting Started​

Begin by updating the script name and file name in the script comments. This will clarify the script's functionality for anyone who reads the code.

Next, adjust the main function to validate and handle the CLI arguments specific to your script.

Your core logic will be housed in the main function.

You can then run your script from the command line using ./shell-script.

Authoring tests​

This template includes a tests/bats directory with a sample Unit and Functional tests written in BATS.

The tests also include a test_helpers.bash file that provides a set of

shell-command.bats is an example of Unit and Functional tests for running the script with different arguments.

The CI supports running the tests with coverage reports uploaded to Codecov.