bash-defensive-patterns

Comprehensive guidance for writing production-ready Bash scripts using defensive programming techniques, error handling, and safety best practices to prevent common pitfalls and ensure reliability. Enable bash strict mode at the start of every script to catch errors early. Key flags: Implement proper cleanup on script exit or error. Always quote variables to prevent word splitting and globbing issues. Use arrays safely for complex data handling. Use [[ ]] for Bash-specific features, [ ] for POSIX. - Writing production automation scripts - Building CI/CD pipeline scripts - Creating system administration utilities - Developing error-resilient deployment automation - Writing scripts that must handle edge cases safely - Building maintainable shell script libraries - Implementing comprehensive logging and monitoring - Creating scripts that must work across different platforms - set -E : Inherit ERR trap in functions - set -e : Exit on any error (command returns non-zero) - set -u : Exit on undefined variable reference - set -o pipefail : Pipe fails if any command fails (not just last) - Always use strict mode - set -Eeuo pipefail - Quote all variables - "$variable" prevents word splitting - Use [[]] conditionals - More robust than [ ] - Implement error trapping - Catch and handle errors gracefully - Validate all inputs - Check file existence, permissions, formats - Use functions...