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Dependency Injector - Python dependency injection framework
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*Dependency Injector* is a Python dependency injection framework. It was 
designed to be unified, developer-friendly tool for managing any kind
of Python objects and their dependencies in formal, pretty way.

*Dependency Injector* framework key features are:

+ Easy, smart, pythonic style.
+ Obvious, clear structure.
+ Extensibility and flexibility.
+ Memory efficiency.
+ Thread safety.
+ Documentation.
+ Semantic versioning.

Status
------

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| *PyPi*                                | .. image:: https://img.shields.io/pypi/v/dependency_injector.svg                |
|                                       |    :target: https://pypi.python.org/pypi/dependency_injector/                   |
|                                       |    :alt: Latest Version                                                         |
|                                       | .. image:: https://img.shields.io/pypi/dm/dependency_injector.svg               |
|                                       |    :target: https://pypi.python.org/pypi/dependency_injector/                   |
|                                       |    :alt: Downloads                                                              |
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|                                       |    :target: https://pypi.python.org/pypi/dependency_injector/                   |
|                                       |    :alt: License                                                                |
+---------------------------------------+---------------------------------------------------------------------------------+
| *Python versions and implementations* | .. image:: https://img.shields.io/pypi/pyversions/dependency_injector.svg       |
|                                       |    :target: https://pypi.python.org/pypi/dependency_injector/                   |
|                                       |    :alt: Supported Python versions                                              |
|                                       | .. image:: https://img.shields.io/pypi/implementation/dependency_injector.svg   |
|                                       |    :target: https://pypi.python.org/pypi/dependency_injector/                   |
|                                       |    :alt: Supported Python implementations                                       |
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| *Builds and tests coverage*           | .. image:: https://travis-ci.org/ets-labs/dependency_injector.svg?branch=master |
|                                       |    :target: https://travis-ci.org/ets-labs/dependency_injector                  |
|                                       |    :alt: Build Status                                                           |
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|                                       |    :target: https://coveralls.io/r/ets-labs/dependency_injector                 |
|                                       |    :alt: Coverage Status                                                        |
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Installation
------------

*Dependency Injector* library is available on PyPi_::

    pip install dependency_injector

Examples
--------

.. code-block:: python

    """Dependency Injector initial example."""

    import sys
    import sqlite3
    import boto.s3.connection

    import services

    from dependency_injector import catalogs
    from dependency_injector import providers
    from dependency_injector import injections


    class Platform(catalogs.DeclarativeCatalog):
        """Catalog of platform service providers."""

        database = providers.Singleton(sqlite3.connect, ':memory:')

        s3 = providers.Singleton(boto.s3.connection.S3Connection,
                                 aws_access_key_id='KEY',
                                 aws_secret_access_key='SECRET')


    class Services(catalogs.DeclarativeCatalog):
        """Catalog of business service providers."""

        users = providers.Factory(services.Users,
                                  db=Platform.database)

        photos = providers.Factory(services.Photos,
                                   db=Platform.database,
                                   s3=Platform.s3)

        auth = providers.Factory(services.Auth,
                                 db=Platform.database,
                                 token_ttl=3600)


    @injections.inject(users_service=Services.users)
    @injections.inject(auth_service=Services.auth)
    def main(argv, users_service, auth_service):
        """Main function."""
        login, password, photo_path = argv[1:]

        user = users_service.get_user(login)
        auth_service.authenticate(user, password)

        upload_photo(user, photo_path)


    @injections.inject(photos_service=Services.photos)
    def upload_photo(user, photo_path, photos_service):
        """Upload photo."""
        photos_service.upload_photo(user['id'], photo_path)


    if __name__ == '__main__':
        main(sys.argv)

You can get more *Dependency Injector* examples in ``/examples`` directory on
GitHub:

    https://github.com/ets-labs/dependency_injector

Documentation
-------------

*Dependency Injector* documentation is hosted on ReadTheDocs:

- `User's guide`_ 
- `API docs`_

Feedback
--------

Feel free to post questions, bugs, feature requests, proposals etc. on
*Dependency Injector*  GitHub Issues:

    https://github.com/ets-labs/dependency_injector/issues

Your feedback is quite important!


.. _PyPi: https://pypi.python.org/pypi/dependency_injector
.. _User's guide: http://dependency-injector.ets-labs.org/en/stable/
.. _API docs: http://dependency-injector.ets-labs.org/en/stable/api/
.. _SLOC: http://en.wikipedia.org/wiki/Source_lines_of_code
.. _SOLID: http://en.wikipedia.org/wiki/SOLID_%28object-oriented_design%29
.. _IoC: http://en.wikipedia.org/wiki/Inversion_of_control
.. _dependency injection: http://en.wikipedia.org/wiki/Dependency_injection