Python Object Extractor

Extract a Python object (like class, function, etc) with its dependencies from a local project into a stand-alone module with a requirements file.

Use cases

The primary use case of this tool is to allow views of a web app's backend to stay organized and conforming to DRY principle while at the same time to be able to be deployed to serverless computing platforms like AWS Lambda, GCP functions, Azure Functions, etc with minimal weight and dependencies' installation time.

Any other use cases are welcome as well.

Deliverables

Package provides executable python-object-extractor.

Synopsis:

usage: python-object-extractor [-h] [-p PROJECT_PATH] [-m OUTPUT_MODULE_PATH]
                               [-r OUTPUT_REQUIREMENTS_PATH]
                               [-n OUTPUT_OBJECT_NAME]
                               object_reference

Extract Python object with its dependencies from local project.

positional arguments:
  object_reference      reference to object to extract. Example:
                        'importable.module:object'

optional arguments:
  -h, --help            show this help message and exit
  -p PROJECT_PATH, --project_path PROJECT_PATH
                        path to local project directory (default: .)
  -m OUTPUT_MODULE_PATH, --output_module_path OUTPUT_MODULE_PATH
                        path to output Python module containing extracted
                        object, for example, 'main.py'. Use '-' to output to
                        STDOUT (default: -)
  -r OUTPUT_REQUIREMENTS_PATH, --output_requirements_path OUTPUT_REQUIREMENTS_PATH
                        path to output requirements file, for example,
                        'requirements.txt'. Use '-' to output to STDOUT
                        (default: -)
  -n OUTPUT_OBJECT_NAME, --output_object_name OUTPUT_OBJECT_NAME
                        output name of target reference. By default it's taken
                        from 'object_reference'. For example, for object
                        reference 'importable.module:object' an output object
                        name will be 'object'  (default: None)

Usage examples

Extract a function from a package located in current directory and print to STDOUT:

python-object-extractor package.module:function

Extract a function from a package located in current directory, name it as main and print results to STDOUT:

python-object-extractor package.module:function -n main

Extract a function from a package located in a given directory and print results to STDOUT:

python-object-extractor package.module:function -p /path/to/project

Extract a function from a package located in a given directory and save results to files main.py and requirements.txt:

python-object-extractor package.module:function -p /path/to/project -m ./main.py -r ./requirements.txt