PyDIO

Lightweight and functional dependency injection library for Python.

Name

PyDIO (stylized as PyDIO, installable as pydio, pronounced "pie-dee-o") stands for Python dependency injection library.

About

PyDIO aims to be simple, yet still powerful, allowing you to feed dependencies inside your application in a flexible way. PyDIO design is based on simple assumption that dependency injection can be achieved using a straightforward key-to-function mapping, where key specifies type of object you want to inject and function is a factory function that creates instances of that type.

In PyDIO, this is implemented using providers and injectors. You use providers to configure your key-to-function mapping, and then you use injectors to perform a lookup of a specific key and creation of the final object.

Here's a simple example:

import abc

from pydio.api import Provider, Injector

provider = Provider()

@provider.provides('greet')
def make_greet():
    return 'Hello, world!'

def main():
    injector = Injector(provider)
    greet_message = injector.inject('greet')
    print(greet_message)

if __name__ == '__main__':
    main()

Now you can save the snippet from above as example.py file and execute to see the output:

$ python example.py
Hello, world!

Key features

• Support for any hashable keys: class objects, strings, ints etc.
• Support for any type of object factories: function, coroutine, generator, asynchronous generator.
• Automatic resource management via generator-based factories (similar to pytest's fixtures)
• Multiple environment support: testing, development, production etc.
• Limiting created object's lifetime to user-defined scopes: global, application, use-case etc.
• No singletons used, so there is no global state...
• ...but you still can create global injector on your own if you need it :-)

Installation

You can install PyDIO using one of following methods:

1. From PyPI (for stable releases):

   $ pip install PyDIO
   

2. From test PyPI (for stable and development releases):

   $ pip install -i https://test.pypi.org/simple/ PyDIO
   

3. Directly from source code repository (for all releases):

   $ pip install git+https://gitlab.com/zef1r/PyDIO.git@[branch-or-tag]
   

Documentation

You have two options available:

1. Visit PyDIO's ReadTheDocs site.

2. Take a tour around functional tests.

Disclaimer

PyDIO is an independent open-source project in the Python ecosystem. It is not affiliated with, sponsored by, or endorsed by any company, organization, or product of the same or similar name. Any similarity in names is purely coincidental and does not imply any association.

License

This project is released under the terms of the MIT license.

See LICENSE.txt for more details.

Author

Maciej Wiatrzyk maciej.wiatrzyk@gmail.com