Typer app

This reference uses Typer for typed parameters and validation while base-cli.attach_typer() supplies the shared lifecycle. Typer remains an optional dependency for applications that prefer annotations and generated help.

Install

python -m pip install "base-cli[typer]"
python -m pip install .
base-typer --help

The example pins the supported Typer range (0.12 through 0.25) because newer releases use a private Click fork that the adapter intentionally rejects.

Configuration

The root command accepts base-cli lifecycle configuration such as --environment, --config, --log-file, --debug, --quiet, and --dry-run. Keep application settings in Typer's typed options or pass an explicit base_cli.App profile when a product needs richer configuration.

Output and errors

base-typer greet --name Ada --count 2 prints two human lines. Typer's native validation reports invalid counts and missing names with non-zero exits; the adapter preserves those exceptions and help text. The hidden --access-code option demonstrates sensitive-parameter redaction.

Tests

python -m pip install "base-cli[dev,typer]"
python -m pytest tests

The tests invoke the generated Click command, not a private Typer implementation.

Completion

_BASE_TYPER_COMPLETE=bash_source base-typer
_BASE_TYPER_COMPLETE=zsh_source base-typer
_BASE_TYPER_COMPLETE=fish_source base-typer

Typer delegates completion to Click; install the generated script in the standard directory for your shell.

Release guidance

Lock the Typer and Click versions together, test the adapter on every supported Python version, run python -m build, and inspect the generated wheel before publishing. Announce adapter support-range changes as release notes.

Operational troubleshooting

• Run with --debug and capture --log-file when diagnosing a command.
• If help fails after a Typer upgrade, check that the version is within the supported >=0.12,<0.28 range.
• Use --count 1 to distinguish application failures from input validation.
• Redact access codes and other credentials from issue reports and transcripts.