PyModuleLoader

PyModuleLoader is a class designed to load and cache in memory Python modules, specified by their dot-paths, as they are accessed. It operates using a Singleton pattern, meaning there can only be one instance of this class in any given Python environment. This means any changes made to PyModuleLoader within a Python session persists throughout the entirety of the session.

The PyModuleLoader also maintains a mapping of dot-paths to their corresponding ‘Abstract Syntax Tree’ (AST) objects. The AST represents Python code in a tree format, where each node corresponds to a Python construct. This enables the object to fetch Python code in an easily manipulatable and readable format.

Example

Here is an example on how to use the PyModuleLoader. Note that this class needs to be initialized before usage, and path information should exist in the specific format that this class expects.

from automata.singletons.py_module_loader import PyModuleLoader as PML
import os

root_path = os.getcwd()  # The root directory path
project_name = 'project'  # The project name

# Initialize the PyModuleLoader with root path and project name
PML.initialize(root_path, project_name)

# Check if a dotpath exist in the loader
print('automata' in PML)  # Replace 'automata' with actual dotpath

# Fetch an existing module dotpath
print(PML.fetch_ast_module('automata'))
# Replace 'automata' with actual dotpath, if the module does not exist, this will return None

# Reset the PyModuleLoader
PML.reset()

Limitations

A specific limitation for PyModuleLoader is that the path information initialization is required before using any method in the class. Also, the Python module loader is designed to operate within a specific directory structure, so if modules are structured differently, adjustments will be needed.

Follow-up Questions:

  • How to handle the cases of different directory structure for Python Modules?

  • What is the best solution to avoid repeating the _assert_initialized call in every single method?

  • What is the strategy to remove type: ignore comments? Is there any sufficient automated method to achieve this?