Uber Shell

uber (prefix) Forming nouns denoting an outstanding, supreme, or pre-eminent example of its kind, or a person or thing markedly surpassing others of its class or type, as uber-fan, uber-model, [uber-shell] etc. Frequently in fashion and popular culture contexts.

A Host/Plugin framework for building powerful interactive REPLs (Read-Eval-Print Loops) in Python.

Uber Shell allows you to:

1. Wrap an existing click CLI into an interactive shell with history and auto-completion.
2. Combine multiple independent CLIs into a single "Meta CLI" using Python Entry Points.
3. Auto-discovery of compatible CLIs using entry-points.
4. Add access to shell commands and other built-in utilities. User extensible.
5. Help automatically builds summary of available commands.

It solves the "slow startup" problem by loading libraries once and running commands repeatedly in memory.

Installation

pip install uber-shell

---

Use Case 1: The "Single App" Mode

Add an interactive loop to your existing CLI tool (e.g., my-app).

1. In your CLI code

Import UberShell and register your Click group.

# my_app/cli.py
import click
from uber_shell import UberShell

@click.group()
def cli():
    pass

@cli.command()
def hello():
    click.echo("Hello World!")

@cli.command()
@click.option("--debug", is_flag=True)
def uber(debug):
    """Starts the interactive shell."""
    shell = UberShell("my-app", debug)

    # Register all commands in 'cli', except 'uber' (to avoid recursion)
    shell.register_click_group(cli, exclude=["uber"])

    shell.start()

if __name__ == "__main__":
    cli()

2. Usage

$ my-app uber
my-app > hello
Hello World!
my-app >

---

Use Case 2: The "Host/Plugin" Mode (The "Uber Uber" Shell)

Create a "Host" application that automatically discovers and runs commands from other installed packages ("Plugins", e.g. quarto-tools, risk-engine).

Step 1: The Plugin (quarto-tools)

In the plugin's pyproject.toml, advertise the CLI entry point.

[project]
name = "quarto_tools"
# ...

# 1. Standard script (creates 'qt' executable)
[project.scripts]
qt = "quarto_tools.cli:entry"

# 2. Plugin Registration (Advertising to Uber Shell)
# The group name "great2.plugins" is an arbitrary contract you define.
[project.entry-points."uber.plugins"]
qt = "quarto_tools.cli:entry"

Don't forget to pip install -e . to register the entry point!

Step 2: The Host

Uber provides a default host application, use load_plugins to find everyone registered under your group name. This code can be duplicated in your own project.

# uber_tools/cli.py
import click
from . import UberShell

@click.group()
def cli():
    pass

@cli.command()
@click.option("--debug", is_flag=True)
def uber(debug):
    """The uber/uber (Master) Shell."""
    shell = UberShell("great2", debug)

    # 1. Register Host commands
    shell.register_click_group(cli, exclude=["uber"])

    # 2. Auto-discover Plugins
    # This scans site-packages for anyone registered to "great2.plugins"
    shell.load_plugins("great2.plugins")

    shell.start()

Step 3: The Experience

The load_plugins method provides Nested Access. If the plugin has an uber command, typing the plugin name (e.g., qt) enters that plugin's specific sub-loop.

$ uber
uber >
uber > archivum
uber > archivum >
uber > archivum > toc       # Runs archivum directly
uber > archivum > ..        # Move up to the parent (also x, q, quit, exit)
uber >
uber > qt toc               # Enter the QT sub-shell and run toc command...
uber > qt > x               # Exit back to host
great2 >

---

Advanced Features

Python Shortcuts

You can register raw Python functions to the shell, bypassing Click entirely.

from my_lib import heavy_calculation

shell.register_command("calc", lambda line: heavy_calculation())

Startup Scripts

You can pass a list of commands to run immediately on startup.

@cli.command()
@click.argument("script", required=False)
def uber(script):
    initial_cmds = [script] if script else None
    shell.start(startup_commands=initial_cmds)

System Fallback

If a command is not found in the registry, UberShell falls back to the system shell. This means you can run dir, git status, or ripgrep directly from the prompt.

great2 > rg "class UberShell"

Built-ins

• cd [path]: Change working directory (smart path completion included).
• cls: Clear screen (Windows).
• ev: Launch "Everything" search (Windows).
• pwd: Print working directory.
• q / x / exit: Quit.

File Structure

uber-shell/
├── pyproject.toml       # Dependencies: click, prompt_toolkit
├── README.md            # The documentation below
├── src/
│   └── uber_shell/
│       ├── __init__.py  # Exposes UberShell and factories
│       └── shell.py     # The core logic
├── docs/                # Documentation (maybe)