Skip to main content

Dependency injection microframework for Python

Project description

https://raw.githubusercontent.com/wiki/ets-labs/python-dependency-injector/img/logo.svg

Latest Version License Supported Python versions Supported Python implementations Downloads Downloads Downloads Wheel Build Status Docs Status Coverage Status

What is Dependency Injector?

Dependency Injector is a dependency injection framework for Python.

It helps implementing the dependency injection principle.

Key features of the Dependency Injector:

  • Providers. Provides Factory, Singleton, Callable, Coroutine, Object, List, Configuration, Dependency and Selector providers that help assembling your objects. See Providers.

  • Overriding. Can override any provider by another provider on the fly. This helps in testing and configuring dev / stage environment to replace API clients with stubs etc. See Provider overriding.

  • Configuration. Read configuration from yaml & ini files, environment variables and dictionaries. See Configuration provider.

  • Containers. Provides declarative and dynamic containers. See Containers.

  • Wiring. Injects dependencies into functions and methods. Helps integrating with other frameworks: Django, Flask, Aiohttp, etc. See Wiring.

  • Typing. Provides typing stubs, mypy-friendly. See Typing and mypy.

  • Performance. Fast. Written in Cython.

  • Maturity. Mature and production-ready. Well-tested, documented and supported.

from dependency_injector import containers, providers
from dependency_injector.wiring import Provide


class Container(containers.DeclarativeContainer):

    config = providers.Configuration()

    api_client = providers.Singleton(
        ApiClient,
        api_key=config.api_key,
        timeout=config.timeout.as_int(),
    )

    service = providers.Factory(
        Service,
        api_client=api_client,
    )


def main(service: Service = Provide[Container.service]):
    ...


if __name__ == '__main__':
    container = Container()
    container.config.api_key.from_env('API_KEY')
    container.config.timeout.from_env('TIMEOUT')
    container.wire(modules=[sys.modules[__name__]])

    main()  # <-- dependency is injected automatically

    with container.api_client.override(mock.Mock()):
        main()  # <-- overridden dependency is injected automatically

When you call main() function the Service dependency is assembled and injected automatically.

When doing a testing you call the container.api_client.override() to replace the real API client with a mock. When you call main() the mock is injected.

You can override any provider with another provider.

It also helps you in configuring project for the different environments: replace an API client with a stub on the dev or stage.

With the Dependency Injector objects assembling is consolidated in the container. Dependency injections are defined explicitly. This makes easier to understand and change how application works.

https://raw.githubusercontent.com/wiki/ets-labs/python-dependency-injector/img/di-readme.svg

Visit the docs to know more about the Dependency injection and inversion of control in Python.

Installation

The package is available on the PyPi:

pip install dependency-injector

Documentation

The documentation is available on the Read The Docs

Examples

Choose one of the following:

Tutorials

Choose one of the following:

Concept

The framework stands on the PEP20 (The Zen of Python) principle:

Explicit is better than implicit

You need to specify how to assemble and where to inject the dependencies explicitly.

The power of the framework is in a simplicity. Dependency Injector is a simple tool for the powerful concept.

Frequently asked questions

What is the dependency injection?
  • dependency injection is a principle that decreases coupling and increases cohesion

Why should I do the dependency injection?
  • your code becomes more flexible, testable and clear 😎

How do I start doing the dependency injection?
  • you start writing the code following the dependency injection principle

  • you register all of your application components and their dependencies in the container

  • when you need a component, you specify where to inject it or get it from the container

What price do I pay and what do I get?
  • you need to explicitly specify the dependencies

  • it will be extra work in the beginning

  • it will payoff as the project grows

Have a question?
Found a bug?
Want to help?
  • ⭐️ Star the Dependency Injector on the Github

  • 🆕 Start a new project with the Dependency Injector

  • 💬 Tell your friend about the Dependency Injector

Want to contribute?
  • 🔀 Fork the project

  • ⬅️ Open a pull request to the develop branch

Release history Release notifications | RSS feed

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

dependency-injector-4.0.4.tar.gz (474.9 kB view hashes)

Uploaded Source

Built Distributions

dependency_injector-4.0.4-pp36-pypy36_pp73-win32.whl (217.3 kB view hashes)

Uploaded PyPy Windows x86

dependency_injector-4.0.4-pp36-pypy36_pp73-manylinux2010_x86_64.whl (334.2 kB view hashes)

Uploaded PyPy manylinux: glibc 2.12+ x86-64

dependency_injector-4.0.4-pp36-pypy36_pp73-macosx_10_9_x86_64.whl (305.9 kB view hashes)

Uploaded PyPy macOS 10.9+ x86-64

dependency_injector-4.0.4-pp27-pypy_73-manylinux2010_x86_64.whl (332.8 kB view hashes)

Uploaded PyPy manylinux: glibc 2.12+ x86-64

dependency_injector-4.0.4-pp27-pypy_73-macosx_10_9_x86_64.whl (307.7 kB view hashes)

Uploaded PyPy macOS 10.9+ x86-64

dependency_injector-4.0.4-cp38-cp38-win_amd64.whl (292.9 kB view hashes)

Uploaded CPython 3.8 Windows x86-64

dependency_injector-4.0.4-cp38-cp38-win32.whl (234.1 kB view hashes)

Uploaded CPython 3.8 Windows x86

dependency_injector-4.0.4-cp38-cp38-manylinux2010_x86_64.whl (2.5 MB view hashes)

Uploaded CPython 3.8 manylinux: glibc 2.12+ x86-64

dependency_injector-4.0.4-cp38-cp38-manylinux2010_i686.whl (2.4 MB view hashes)

Uploaded CPython 3.8 manylinux: glibc 2.12+ i686

dependency_injector-4.0.4-cp38-cp38-macosx_10_9_x86_64.whl (437.7 kB view hashes)

Uploaded CPython 3.8 macOS 10.9+ x86-64

dependency_injector-4.0.4-cp37-cp37m-win_amd64.whl (273.7 kB view hashes)

Uploaded CPython 3.7m Windows x86-64

dependency_injector-4.0.4-cp37-cp37m-win32.whl (223.5 kB view hashes)

Uploaded CPython 3.7m Windows x86

dependency_injector-4.0.4-cp37-cp37m-manylinux2010_x86_64.whl (2.0 MB view hashes)

Uploaded CPython 3.7m manylinux: glibc 2.12+ x86-64

dependency_injector-4.0.4-cp37-cp37m-manylinux2010_i686.whl (1.8 MB view hashes)

Uploaded CPython 3.7m manylinux: glibc 2.12+ i686

dependency_injector-4.0.4-cp37-cp37m-macosx_10_9_x86_64.whl (421.4 kB view hashes)

Uploaded CPython 3.7m macOS 10.9+ x86-64

dependency_injector-4.0.4-cp36-cp36m-win_amd64.whl (273.0 kB view hashes)

Uploaded CPython 3.6m Windows x86-64

dependency_injector-4.0.4-cp36-cp36m-win32.whl (224.0 kB view hashes)

Uploaded CPython 3.6m Windows x86

dependency_injector-4.0.4-cp36-cp36m-manylinux2010_x86_64.whl (2.0 MB view hashes)

Uploaded CPython 3.6m manylinux: glibc 2.12+ x86-64

dependency_injector-4.0.4-cp36-cp36m-manylinux2010_i686.whl (1.9 MB view hashes)

Uploaded CPython 3.6m manylinux: glibc 2.12+ i686

dependency_injector-4.0.4-cp36-cp36m-macosx_10_9_x86_64.whl (455.9 kB view hashes)

Uploaded CPython 3.6m macOS 10.9+ x86-64

dependency_injector-4.0.4-cp35-cp35m-win_amd64.whl (257.5 kB view hashes)

Uploaded CPython 3.5m Windows x86-64

dependency_injector-4.0.4-cp35-cp35m-win32.whl (210.8 kB view hashes)

Uploaded CPython 3.5m Windows x86

dependency_injector-4.0.4-cp35-cp35m-manylinux2010_x86_64.whl (1.9 MB view hashes)

Uploaded CPython 3.5m manylinux: glibc 2.12+ x86-64

dependency_injector-4.0.4-cp35-cp35m-manylinux2010_i686.whl (1.8 MB view hashes)

Uploaded CPython 3.5m manylinux: glibc 2.12+ i686

dependency_injector-4.0.4-cp35-cp35m-macosx_10_9_x86_64.whl (419.7 kB view hashes)

Uploaded CPython 3.5m macOS 10.9+ x86-64

dependency_injector-4.0.4-cp27-cp27mu-manylinux2010_x86_64.whl (1.6 MB view hashes)

Uploaded CPython 2.7mu manylinux: glibc 2.12+ x86-64

dependency_injector-4.0.4-cp27-cp27mu-manylinux2010_i686.whl (1.5 MB view hashes)

Uploaded CPython 2.7mu manylinux: glibc 2.12+ i686

dependency_injector-4.0.4-cp27-cp27m-manylinux2010_x86_64.whl (1.6 MB view hashes)

Uploaded CPython 2.7m manylinux: glibc 2.12+ x86-64

dependency_injector-4.0.4-cp27-cp27m-manylinux2010_i686.whl (1.5 MB view hashes)

Uploaded CPython 2.7m manylinux: glibc 2.12+ i686

dependency_injector-4.0.4-cp27-cp27m-macosx_10_9_x86_64.whl (410.2 kB view hashes)

Uploaded CPython 2.7m macOS 10.9+ x86-64

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page