What is it?
Is just a dependency injector
it's a design pattern for maintain high level on the software quality http://docs.djangoproject.com/en/dev/misc/design-philosophies/?from=olddocs
** and is not a Service Locator.**
is useful for small-sized projects, when you want to maintain decency in your code without using invasive frameworks
is useful if you want to test the code, to give a mock object dependencies
is useful to understand how work a stupid dependency injector
is useful to reuse the code
is NOT useful if you have a lot of injected object, is better use a Service Locator and a PROPER DIC framework.
injection without instantiation, using metaclass ??
What is a Dependency Injection or DI?
How it works?
from di import * # instance = inject(Class, tuple of parameters) EmailSender = inject(Mailer, dispatcher=SmtpLibV02) # EmailSender is now instantiated # and has the attribute 'dispatcher' with SmtpLib instantiated
please fork it and add some ideas :)
git clone firstname.lastname@example.org:liuggio/Ultra-Lightweight-Dependency-Injector-Python.git di cd di python example.py
from types import * def inject(class_holder, **dependencies): if isinstance(class_holder, ClassType): istance = class_holder() else: istance=class_holder for dependency in dependencies: if isinstance(dependencies[dependency], ClassType): dependencies[dependency]=dependencies[dependency]() setattr(istance, dependency, dependencies[dependency]) return istance