fundi 0.0.8

Dependency injection library

# FunDI

Solution for problem no one had before

Fun stays for function(or for fun if you wish) and DI for Dependency Injection

This library provides fast(to write!) and convenient(to use!) Dependency Injection for functional programming on python.

Why?

This library was inspired by FastAPI's dependency injection. The reasons for its existence are simple:

• A standalone dependency injection library. DI shouldn't be tied to a specific framework.
• It simplifies code writing. Dependency injection reduces boilerplate and improves maintainability.
• Lack of DI libraries for functional programming in Python. Or maybe I just didn't want to find one :3

No more words, let's try!

from contextlib import ExitStack

from fundi import scan, from_, inject


def require_user():
    return "Alice"


def greet(user: str = from_(require_user)):
    print(f"Hello, {user}!")


with ExitStack() as stack:
    inject({}, scan(greet), stack)

See the documentation to get more examples: https://fundi.readthedocs.io/en/latest/

Component explanation:

• fundi.from_ - Helps define dependencies.

  Use cases:

  • Tell resolver to resolve parameter value by its type, not name (ex: parameter: from_(Session))

  • Define dependency (ex: parameter: type = from_(dependency)).

    In this case it can be replaced with fundi.scan.scan (ex: parameter: type = scan(dependency))

• fundi.scan - Scans function for dependencies. Returns CallableInfo object that is used by all functions that resolve dependencies.

• fundi.order - returns order in which dependencies will be resolved

• fundi.tree - returns dependency resolving tree