[FEATURE] Add easy --version

Is your feature request related to a problem

I’d like a way to do the standard my-command --version to exit an print the version number of the application. Click offers a version_option decorator that you can put on the entrypoint of your application to achieve this relatively easily.

The solution you would like

The ability to pass in a version string to an application and have the option added automatically. I’d then end up doing something like this:

from importlib.metadata import version

app = typer.Typer(version=version(__package__))

Though if it’s possible to attempt to extract the package version automatically without having to pass it in, that would be even better.

Describe alternatives you’ve considered

I attempted to just add a version option in my callback like below, but I can’t seem to call this without passing in a command.

@app.callback()
def cli(display_version: bool = typer.Option(False, "--version")) -> None:
    if display_version:
        print(f"Version: {version(__package__)}")
        raise typer.Exit()

However if I just try my-command --version it gives me an error saying I need to pass a command. It would be nice to be able to add custom top level options like --help which are allowed to run. Then users could implement things like --version themselves.

[dbanty]

@kesavkolla yes you just add a callback function for your app and then use the --version parameter in that callback.

Docs on callback: https://typer.tiangolo.com/tutorial/commands/callback/

Docs on --version: https://typer.tiangolo.com/tutorial/options/version/

Example combining the two:

import typer

app = typer.Typer()

def version_callback(value: bool):
    if value:
        typer.echo(f"Awesome CLI Version: {__version__}")
        raise typer.Exit()

@app.callback()
def main(
    version: bool = typer.Option(None, "--version", callback=version_callback, is_eager=True),
):
    # Do other global stuff, handle other global options here
    return

[shelper]

would it be even greater if the version value is read from poetry’s pyproject.toml file?

maybe something like a typer plugin for poetry, so it generates this version CLI option automatically?