Bash Script Generator

Create enterprise Bash automation scripts with safe strict modes, traps, error handling, and argument parsing.

- Fails on any error, unset variables, and errors in pipes.
- Adds a trap function to catch unexpected exits.
- Verifies that the script is run with sudo/root.
- Prevent concurrent executions using a lock file.
- Keeps global scope clean.
- Provides log_info, log_warn, log_err functions.

Your core bash commands.

script.sh

Usage Instructions

# 1. Save the file

nano script.sh


# 2. Make the script executable

chmod +x script.sh


# 3. Run the script

./script.sh


# 4. (Optional) Run ShellCheck to verify

shellcheck script.sh

Overview

Bash is the most widely used shell on Linux systems. However, writing robust, production-ready bash scripts requires strict error handling, environment isolation, and safety checks. This generator enforces enterprise standards like set -euo pipefail and traps.

Best Practices for Production

  • Always use double quotes: Unquoted variables can cause word splitting and globbing, leading to dangerous bugs.
  • Validate input: Never trust user arguments or environment variables. Provide a fallback or exit if they are missing.
  • Wrap in main(): Putting your logic inside a `main()` function prevents variable leakage into the global scope.
  • Use ShellCheck: Always run your scripts through `shellcheck` before deploying to production.

Common Mistakes

rm -rf $DIR/: If $DIR is unset, this becomes `rm -rf /`, wiping the entire server. Always quote and check variables, or enable `set -u`.

Bashisms in /bin/sh: If your shebang is `#!/bin/sh`, you cannot use Bash arrays or `[[ ]]`. Always use `#!/usr/bin/env bash` for Bash scripts.

Frequently Asked Questions

What does set -euo pipefail do?
Also known as 'Bash Strict Mode'. -e exits immediately if a command fails. -u exits if an unset variable is used. -o pipefail catches errors within piped commands (e.g., if a fails in a | b).
Why should I use a trap?
A trap executes a function when the script exits, whether it succeeds, fails, or is interrupted (like with Ctrl+C). It's crucial for cleaning up temporary files or releasing lock files.
Why shouldn't I run curl | bash?
Piping a script directly from the internet to bash means you have no chance to inspect it. If the connection drops halfway, bash will execute a partial, potentially destructive script.