What is the best way to wrap an existing CLI tool using Typer?

[sidekick-eimantas]

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Example Code

import sys

import typer


app = typer.Typer(
    no_args_is_help=False,
    add_completion=False,
    pretty_exceptions_enable=False,
    add_help_option=False,
)

EXTENSIONS: list[str] = [
    "list-modified-stacks",
    "upload-plan",
]
MODE: typing.Literal["extend", "proxy"] = "proxy"


for extension in EXTENSIONS:
    if extension in sys.argv:
        MODE = "extend"
        break


if MODE == "extend":
    @app.command
    def list_modified_stacks(...) -> None:
        ...


if MODE == "proxy":
    @app.callback(invoke_without_command=True, context_settings={"allow_extra_args": True, "ignore_unknown_options": True})
    def proxy(ctx: typer.Context) -> None:
        ...

Description

The example code above is the best way I could figure out to wrap an existing CLI tool with Typer.
Effectively, if a command that the wrapper is implementing is called, we define the command at runtime and use Typer as normal. If any other command is called, we proxy it through to the original CLI tool, maybe doing some work inbetween.

Is there a better way of achieving this? Does Typer have any 1st class support for implementing wrappers?

Operating System

macOS

Operating System Details

No response

Typer Version

0.7.0

Python Version

Python 3.10.7

Additional Context

No response