Simple Python Plugin Loader

This module provides a simple way to dynamically load other Python modules as Plugins to your current project.

Install

You can install this python module via pip:

pip install simple-plugin-loader

Otherwise the module can be downloaded from PyPI: https://pypi.org/project/simple-plugin-loader/

Usage

1. Import the module:

   from simple_plugin_loader import Loader
   

2. Load your plugins/modules:

   # initialize the loader
   loader = Loader()
   
   # load your plugins
   plugins = loader.load_plugins(<plugin_path>, <plugin_base_class>, <specific_plugins>, <recursive>)
   

3. (Optional) The already loaded plugins/modules can be accessed via the plugins property of the loader instance:

   plugins = loader.plugins
   

load_plugins(...) Method

This method does the actual plugin loading.

It loads only Python modules that can be executed in the current environment. For every successfully loaded module a message is populated through the Python logging library (log level: INFO).

If a module e.g. contains syntax errors or depends on other not installed Python modules, it will be skipped. So the main program does not fail completely. An error message is populated through the Python logging library (log level: ERROR).

Arguments

• <plugin_path>: str
  This string represents the path (relative or absolute) to the directory from where the plugins/modules should be loaded.
• <plugin_base_class>: class (Default: SamplePlugin)
  The Loader does not load all found modules that are in the above directory. It only loads classes that are sub-classes of the here specified class.
  The default value of this argument is the SamplePlugin class. You can use this class as the base class for your plugins:

  from simple_plugin_loader.sample_plugin import SamplePlugin
  
  class YourPlugin(SamplePlugin):
      pass
  

• <specific_plugins>: List[str] (Default: [])
  This list can contain case sensitive class names, that should be loaded. Then no other plugins will be loaded. The argument <plugin_base_class> will also be ignored, so any class can be loaded.
• <recursive>: bool (Default: False)
  Set this flag to True if you wish to load plugins/modules recursively to the above directory.

Return value

The method returns a dictionary that has the following structure:

• Key: The name of the plugin/module. This name is the module name of the module that contains the plugin class.
• Value: The plugin class. Not an instance!