python-dependency-injector/README.md
2015-03-18 01:16:59 +02:00

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Objects
=======
Python catalogs of objects providers
[![Latest Version](https://pypip.in/version/Objects/badge.svg)](https://pypi.python.org/pypi/Objects/)
[![Downloads](https://pypip.in/download/Objects/badge.svg)](https://pypi.python.org/pypi/Objects/)
[![Build Status](https://travis-ci.org/rmk135/objects.svg?branch=master)](https://travis-ci.org/rmk135/objects)
[![Coverage Status](https://coveralls.io/repos/rmk135/objects/badge.svg)](https://coveralls.io/r/rmk135/objects)
[![License](https://pypip.in/license/Objects/badge.svg)](https://pypi.python.org/pypi/Objects/)
Example:
```python
"""Concept example of Objects."""
from objects import AbstractCatalog
from objects.providers import Singleton
from objects.providers import NewInstance
from objects.injections import InitArg
from objects.injections import Attribute
import sqlite3
class ObjectA(object):
"""Example class ObjectA, that has dependency on database."""
def __init__(self, db):
"""Initializer."""
self.db = db
class ObjectB(object):
"""Example class ObjectB, that has dependencies on ObjectA and database."""
def __init__(self, a, db):
"""Initializer."""
self.a = a
self.db = db
class Catalog(AbstractCatalog):
"""Catalog of objects providers."""
database = Singleton(sqlite3.Connection,
InitArg('database', ':memory:'),
Attribute('row_factory', sqlite3.Row))
""":type: (objects.Provider) -> sqlite3.Connection"""
object_a = NewInstance(ObjectA,
InitArg('db', database))
""":type: (objects.Provider) -> ObjectA"""
object_b = NewInstance(ObjectB,
InitArg('a', object_a),
InitArg('db', database))
""":type: (objects.Provider) -> ObjectB"""
# Catalog static provides.
a1, a2 = Catalog.object_a(), Catalog.object_a()
b1, b2 = Catalog.object_b(), Catalog.object_b()
# Some asserts.
assert a1 is not a2
assert b1 is not b2
assert a1.db is a2.db is b1.db is b2.db is Catalog.database()
```