modern-di-litestar 2.8.0

Modern-DI integration for LiteStar

"Modern-DI-LiteStar"

Integration of Modern-DI with Litestar.

Usage example: litestar-sqlalchemy-template

📚 Documentation

Installation

pip install modern-di-litestar

Quick start

1. Define providers

import dataclasses
from modern_di import Group, Scope, providers


@dataclasses.dataclass(kw_only=True)
class Database:
    url: str


@dataclasses.dataclass(kw_only=True)
class UserRepository:
    db: Database


class AppDependencies(Group):
    database = providers.Factory(creator=Database, kwargs={"url": "sqlite:///app.db"})
    user_repo = providers.Factory(scope=Scope.REQUEST, creator=UserRepository, bound_type=None)

2. Wire the plugin

import litestar
from modern_di import Container
from modern_di_litestar import ModernDIPlugin

groups = [AppDependencies]

app = litestar.Litestar(
    plugins=[ModernDIPlugin(Container(groups=groups), autowired_groups=groups)],
)

Passing autowired_groups to ModernDIPlugin auto-registers each provider as a Litestar dependency keyed by its attribute name (database, user_repo), so routes can declare them directly as parameters.

3. Inject into routes

Using FromDI (explicit, per-route)

from modern_di_litestar import FromDI

@litestar.get(
    "/users",
    dependencies={"repo": FromDI(AppDependencies.user_repo)},
)
async def list_users(repo: UserRepository) -> list[str]:
    ...

FromDI accepts either a provider instance (AppDependencies.user_repo) or a type (UserRepository).

Using auto-wired group names (implicit)

When autowired_groups is passed to ModernDIPlugin, provider names become available as route parameters directly:

@litestar.get("/users")
async def list_users(user_repo: UserRepository) -> list[str]:
    ...

4. Access the raw request or websocket via DI

from modern_di_litestar import litestar_request_provider, litestar_websocket_provider

class AppDependencies(Group):
    ...
    request_method = providers.Factory(
        scope=Scope.REQUEST,
        creator=lambda request: request.method,
        bound_type=None,
    )

litestar_request_provider and litestar_websocket_provider are pre-built ContextProvider instances that make the current Request / WebSocket objects resolvable within DI.

5. Sub-request (action) scopes

For work that should live shorter than a request, build a child container inside a route:

@litestar.get("/")
async def handler(di_container: Container) -> None:
    action_container = di_container.build_child_container()
    result = action_container.resolve_provider(AppDependencies.some_action_scoped_factory)

6. Retrieve the app-level container

from modern_di_litestar import fetch_di_container

container = fetch_di_container(app)

Public API

Symbol	Description
ModernDIPlugin(container, autowired_groups=None)	Litestar InitPlugin — wires the DI container into app lifecycle
FromDI(provider)	Returns a Litestar Provide that resolves a provider per request
litestar_request_provider	ContextProvider for the current litestar.Request
litestar_websocket_provider	ContextProvider for the current litestar.WebSocket
fetch_di_container(app)	Retrieves the root container from app.state
build_di_container	Internal Litestar dependency — creates a scoped child container per request