cli-boilerplate

CLI boilerplate

Purpose: Starter CLI — arg parsing, --help, leveled logging, exit codes. · Lang: TS + Python · Deps: none (tsx dev-only) Copy to: your project. · Use when: standing up a new Node or Python command-line script.

A starting point for a command-line script, in both Node (TypeScript) and Python. Copy the file in your language of choice, rename the demo greet command, and you have a CLI with argument parsing, --help, --version, leveled logging, and proper exit codes already wired up.

Zero runtime dependencies. Everything is built-in:

• Python — argparse and logging are stdlib. Needs Python 3.8+.
• Node — argument parsing is node:util parseArgs (built in, Node 18.3+); logging is a ~10-line leveled console logger in the file. tsx is only a dev tool to run the TS directly — nothing ships at runtime.

Run it

# Python
python cli.py --help
python cli.py greet World
python cli.py -v greet World           # DEBUG logging
python cli.py -q greet World           # warnings/errors only
python cli.py --version

# Node
npx tsx cli.ts --help
npx tsx cli.ts greet World --times 3
npx tsx cli.ts --version

Both print the same thing for the demo command:

$ python cli.py greet World
Hello, World!

What you get

Feature	Python	Node
Arg parsing	argparse (stdlib)	node:util parseArgs (built in)
--help / -h	automatic from argparse	printed USAGE string
--version	action="version"	handled in main
Verbosity	-v/--verbose, -q/--quiet → logging level	same flags → tiny leveled logger
Demo action	greet <name> subcommand	greet <name> command
Exit codes	0 ok · 1 runtime error · 2 usage · 130 Ctrl-C	0 ok · 1 runtime error · 2 usage

Logs go to stderr, real output to stdout — so the program stays pipe-friendly (cli.py greet World | cat gets just the greeting, not the log noise).

Copy-in tweaks

• Rename greet to your real command and put the work in its handler (cmd_greet / cmdGreet).
• Bump VERSION (or wire it to package metadata: read package.json in Node, importlib.metadata.version(...) in Python).
• Add more subcommands: another sub.add_parser(...) in Python, another case in the Node command switch.

Notes

• Cross-platform — no macOS-specific calls here, unlike most snippets in this repo. Both run the same on Linux/CI.
• The two versions are intentionally close in shape so you can keep a project's Python and Node CLIs feeling consistent. They are independent files, though — copy only the one you need.