ewok 0.4.4

Education Warehouse Octopus Kit - Extensible CLI framework with plugin support

Ewok - Education Warehouse Octopus Kit

Ewok (Education Warehouse Octopus Kit) is a powerful CLI framework built on top of Invoke and Fabric. It extends them with features for plugin-based, composable command-line tools.

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Quick Start

Follow these steps to create a basic Ewok-powered CLI.

1. Example Project structure

my_project/
├── src/
│   └── my_package/
│       ├── __init__.py
│       └── tasks.py
├── pyproject.toml

You can merge your CLI into __init__.py for simplicity.

2. Define your Ewok app

# src/my_package/__init__.py
from ewok import App
from . import tasks

app = App(
    name="myapp",
    version="0.1.0",
    core_module=tasks,
)

3. Define a task

# src/my_package/tasks.py
from ewok import task, Context
# you can also import Context from invoke instead; ewok.Context is an alias


@task
def hello(c: Context, name: str = "world"):
    """Print a friendly greeting"""
    print(f"Hello, {name}!")

4. Configure pyproject.toml

[project]
name = "my-project"
version = "0.1.0"
dependencies = [
    "ewok>=0.1.0",
    # other dependencies...
]

[project.scripts]
myapp = "my_package:app"

myapp will be installed as an executable that runs the app object.

5. Install in development mode

#  The `-e` flag performs an editable install — useful while developing.
uv pip install -e .

Then try your CLI:

myapp hello --name Alice

Hello, Alice!

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Features

• Multi-source Task Integration:

  • Core tasks from your package
  • Plugin tasks via entry points (namespaced)
  • Personal tasks from ~/.config/<name>/tasks.py
  • Project-local tasks.py (namespaced as local.)
  • Extra namespaced modules like dev.tasks.py → dev.taskname

• Plugin System: Discover and load tasks from external packages

• Flexible Namespacing: Mix-and-match functionality per project, plugin, and personal

• Invoke/Fabric Compatible: Supports all base task features

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Creating an Ewok App

Ewok’s App class wraps and extends Invoke’s CLI system.

Ewok-specific arguments

These options extend the default behavior of Invoke/Fabric:

Parameter	Description	Default
name	Name of your CLI tool (used in help/version)	Required
version	App version string	Required
core_module	Your main task module	Required
extra_modules	Tuple of additional task modules (each auto-namespaced)	()
plugin_entrypoint	Entry point group(s) for plugin discovery	name
config_dir	Where to look for personal tasks (e.g. ~/.config/<name>)	~/.config/{name}
include_project	Load project-specific *.tasks.py modules	True
include_local	Load tasks.py from the current directory (under local. namespace)	True
ewok_modules	Include Ewok's own internal modules (not in use yet)	True

Ewok extensions to @task()

In addition to the standard @task() parameters from Invoke/Fabric, Ewok supports two additional parameters:

The flags Parameter

Type: dict[str, list[str]]

The flags parameter allows you to define additional CLI flags that map to boolean function parameters:

@task(flags={'exclude': ['--exclude', '-x'], 'as_json': ['--json']})
def deploy(c: Context, exclude: bool = False, as_json: bool = False):
    """Deploy with optional exclusions and JSON output"""
    if exclude:
        print("Excluding test files...")
    c.run("echo 'some shell command'")
    if as_json:
        return {"status": "deployed"}
    print("Deployment complete!")

This enables calling your task with the defined flags:

myapp deploy --exclude --json
# or using the short form:
myapp deploy -x --json

The hookable Parameter

Type: Optional[bool]

Controls whether the task can participate in "hook" chaining behavior:

• True → This is a core task that can trigger other tasks with the same name (e.g., from plugins or local modules) after it runs.
• False → This task should not be hooked, even if another with the same name exists. Typically used in plugins or local overrides.
• None (default) → Default behavior: core tasks don't hook; plugin/local tasks can be hooked.

Example

Here's a concrete example showing how the hook system works with a setup task:

Core module (tasks.py):

@task(hookable=True)
def setup(c: Context):
    """Core setup - runs first, triggers other setup tasks"""
    print("🔧 Core setup: Creating docker-compose.yml and .env files...")
    # Create essential config files that every project needs
    create_docker_compose()
    create_env_template()

Local tasks (tasks.py in project directory):

@task  # hookable=None (default) - will be called after core
def setup(c: Context):
    """Project-specific setup questions"""
    print("🏠 Local setup: Configuring project settings...")
    check_env(
        key="DOMAIN",
        default="localhost",
        comment="The hosting domain for this project"
    )
    set_file_permissions()

Plugin (backup plugin):

@task  # hookable=None (default) - will be called after core  
def setup(c: Context):
    """Backup plugin setup"""
    print("💾 Backup setup: Configuring backup storage...")
    check_env(
        key="BACKUP_PATH",
        default=get_default_backup_path(),
        comment="Where backups should be stored"
    )

Plugin with non-hookable task (e.g. nuke.tasks.py):

@task(hookable=False)  # This will NOT run automatically
def setup(c: Context):
    """Destructive setup - only run when explicitly called"""
    print("💣 Nuclear setup: This will destroy existing config!")
    # Only runs when called as: myapp nuke.setup

Execution flow for this example when you run myapp setup:

1. Core setup runs first (creates base files)
2. Plugin setup runs next (configures backup storage)
3. Local setup runs last (asks project-specific questions)
4. setup with hookable=False does NOT run (because it's explicitly excluded from the hook chain)

This allows you to build layered functionality where each level can extend the setup process, but dangerous or unrelated operations require explicit invocation.

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Plugin System

Ewok supports plugin discovery via Python entry points, allowing you to extend your CLI with external packages.

Example: Creating a Plugin

1. Create a plugin package with its own tasks.py:

# my_plugin/tasks.py
from ewok import task

@task
def greet(c):
    """Plugin greeting task"""
    print("Hello from the demo plugin!")

@task
def status(c):
    """Show plugin status"""
    print("Demo plugin is active")

2. Register the plugin in the plugin's pyproject.toml:

[project.entry-points.myapp]  # Must match your main app's name
demo = "my_plugin.tasks"      # 'demo' becomes the namespace prefix

The entry point name (demo in this example) determines the namespace. Tasks from this plugin will be accessible as demo.greet, demo.status, etc.

3. Install and use the plugin:

# Install the plugin package
uv pip install my-plugin-package

# Use the plugin tasks
myapp demo.greet   # Calls the greet task from the demo namespace
myapp demo.status  # Calls the status task from the demo namespace

Discovering under multiple entry point names

You can configure your app to discover plugins from multiple entry point groups:

app = App(
    name="myapp",
    version="1.0.0",
    core_module=tasks,
    plugin_entrypoint=("myapp", "myapp_plugins"),  # Search both groups
)

This allows plugin authors to register under either myapp or myapp_plugins entry points.

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Command Organization

Task sources and their namespaces:

Source	Example Call	Namespace
Core task module	myapp hello	global
Plugin via entry point	myapp demo.taskname	demo.
Project-local tasks.py	myapp local.taskname	local.
Namespaced dev.tasks.py	myapp dev.taskname	dev.
Personal ~/.config/myapp/	myapp taskname	global

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CLI Flags

Control which task sources are loaded at runtime:

Flag	Description
--no-local	Skip tasks.py in the current directory
--no-project	Skip namespaced *.tasks.py in the project
--no-personal	Skip ~/.config/<name>/tasks.py
--no-plugins	Skip plugin discovery entirely
--no-packaged	Skip installed plugin packages
--no-ewok	Skip Ewok’s own built-in modules

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Full Example

# src/my_package/__init__.py
from pathlib import Path
from ewok import App
from . import tasks, extra, slow
from .__about__ import __version__

app = App(
    name="my-app",
    version=__version__,
    core_module=tasks,  # not namespaced
    extra_modules=(extra, slow),  # namespaced as `extra.` and `slow.`
    plugin_entrypoint=("my-app", "myapp_plugins"),
    # only if it differs from 'name', can also be multiple or None to disable
    config_dir=Path("~/custom-config/my-app"),  # only if it differs from 'name', can also be a Path or None to disable
    include_project=True,  # to include project-specific tasks.py and <namespace>.tasks.py files
    include_local=True,  # to include tasks.py in the local cwd and up your file tree (../tasks.py etc.)
)

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Examples & Resources

• 🧪 Minimal template: ewok-example
• 🧰 Real-world usage: edwh

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License

MIT License