Dismantle

Dismantle Python package / plugin / extension manager.

"""Simple plugin example"""
from dismantle import plugin


class Chat():
    @plugin.register('chat.message')
    def show(self, message):
        print(message)


@plugin.plugin('chat.message', order=-1)
def make_uppercase(message):
    return message.upper()

"""Full example using all aspects."""
from pathlib import Path
from dismantle.extension import Extensions, IExtension
from dismantle.index import JsonFileIndexHandler
from dismantle.package import LocalPackageHandler


class ColorExtension(IExtension):
    _category = 'color'

    def color(self) -> None:
        ...


class GreenColorExtension(ColorExtension):
    _name = 'green'

    def color(self) -> None:
        print(f'color is {self._name}')


packages = {}
index = JsonFileIndexHandler('index.json')
for pkg_meta in index:
    meta = index[pkg_meta]
    path = datadir.join(meta['path'])
    package = LocalPackageHandler(meta['name'], path)
    package._meta = {**package._meta, **meta}
    package.install()
    packages[package.name] = package
extensions = Extensions([ColorExtension], packages, 'ext_')
assert extensions.types == ['color']
assert list(extensions.category('color').keys()) == [
    '@scope-one/package-one.extension.green.GreenColorExtension',
    '@scope-one/package-two.extension.red.RedColorExtension',
    '@scope-one/package-three.extension.blue.BlueColorExtension',
]
assert list(extensions.extensions.keys()) == ['color']
assert list(extensions.imports.keys()) == [
    '@scope-one/package-one.extension.green',
    '@scope-one/package-two.extension.red',
    '@scope-one/package-three.extension.blue'
]

Dismantle allows you to provide the ability to create a plugin/extension/module for an application. It does this by checking a package index and using that index to manage package versions. Packages then contain plugins (using decorators) and extensions (using a custom module loader) to add the additional functionality to the application.

Installing Dismantle and Supported Versions

Dismantle is available on PyPI:

$ python -m pip install dismantle

Dismantle officially supports Python 3.7+.

Supported Features & Best–Practices

Dismantle is ready for the demands of providing flexibility within applications allowing developers to build rich ecosystems around core applications.

Index Management

easy to create custom index handlers providing additional ways to define package indexes
local index file support using json
url based index file support using json
etag based caching for url based index

Packaging

easy to create custom package handlers providing additional ways to define package sources
easy to create custom package formats compression types and structures
support for zip, tar.gz, tgz, and local directories as package formats
support for local and url based (http/https) package handlers
hash validation for packages with the ability to verify package integrity

Extensions

Categorized extension groups to filter extension types (eg. loggers, parsers, ...)
Support for init or .py based module loading.
Extension activation and deactivation management.
Module name collision avoidance
Hierarchical module naming

Plugins

Decorator based plugins with pre and post value modification
Multiple plugins per function with ability to set execution order
Activation management