Factories

Registering the dependency’s instance is not the only way of telling injectme what object to use during “injection” phase. You can also register “factories”, simple callables returning instances of dependencies.

To register a factory instead of single instance use injectme.register_factory() or injectme.DependenciesRegistry.register_factory().

The registered factory should not require any arguments. The returned value will be set as an instance of corresponding dependency. The factory will be called each time an instance is needed for injecting.

Example:

example.py

from injectme import inject, register_factory


class Dependency:
    pass


@inject
class Example:
    dep: Dependency


def dependency_factory():
    print("Creating new dependency")
    return Dependency()


register_factory(Dependency, dependency_factory)

print("First injection")
Example()

print("Second injection")
Example()

$ python3 example.py

First injection
Creating new dependency
Second injection
Creating new dependency