inversipy 0.3.0

A powerful and type-safe dependency injection/IoC library for Python

inversipy

A powerful and type-safe dependency injection/IoC (Inversion of Control) library for Python 3.12+.

Features

• Type annotation-based - Dependencies resolved using Python type hints
• Pure classes - No container coupling; classes remain framework-agnostic
• Zero runtime dependencies - Pure Python
• Async-first - First-class support for async dependencies and factories
• Module system - Organize dependencies with public/private access control
• Multiple scopes - Singleton, Transient, and Request
• Named dependencies - Multiple implementations with named disambiguation
• Collection injection - Register and inject multiple implementations with InjectAll
• Optional dependencies - T | None parameters resolve to None when unregistered
• Container freezing - Lock the container after configuration
• Validation - Catch configuration errors at startup
• FastAPI integration - @inject decorator for route handlers
• Full type safety - Strict MyPy support with py.typed marker

Installation

pip install inversipy

Quick Start

from inversipy import Container, Scopes

class Database:
    def query(self, sql: str) -> list:
        return ["result"]

class UserRepository:
    def __init__(self, db: Database) -> None:
        self.db = db

    def get_users(self) -> list:
        return self.db.query("SELECT * FROM users")

class UserService:
    def __init__(self, repo: UserRepository) -> None:
        self.repo = repo

    def list_users(self) -> list:
        return self.repo.get_users()

# Create container and register dependencies
container = Container()
container.register(Database, scope=Scopes.SINGLETON)
container.register(UserRepository)
container.register(UserService)

# Validate and freeze
container.validate()
container.freeze()

# Resolve dependencies
service = container.get(UserService)
users = service.list_users()

Documentation

Full documentation is available at the documentation site.

• Getting Started
• Core Concepts
• Injection Patterns
• FastAPI Integration
• Testing
• Best Practices

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

MIT License - see LICENSE file for details.

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