dishka-faststream 0.0.2

Integration package for Dishka DI and FastStream framework

FastStream

Though it is not required, you can use dishka-faststream integration. It features:

• automatic REQUEST scope management using middleware
• passing StreamMessage and ContextRepo object as a context data to providers
• automatic injection of dependencies into message handler.

You can use auto-injection for FastStream 0.5.0 and higher. For older version you need to specify @inject manually.

Note

If you are using FastAPI plugin of FastStream you need to use both dishka integrations, but you can share the same container.

• Call dishka.integrations.faststream.setup_dishka on faststream broker or router.
• Call dishka.integrations.fastapi.setup_dishka on fastapi app.

How to use

1. Import

from dishka.integrations.faststream import (
    FromDishka,
    inject,
    setup_dishka,
    FastStreamProvider,
)
from dishka import make_async_container, Provider, provide, Scope

2. Create provider. You can use faststream.types.StreamMessage and faststream.ContextRepo as a factory parameter to access on REQUEST-scope

class YourProvider(Provider):
    @provide(scope=Scope.REQUEST)
    def create_x(self, event: StreamMessage) -> X:
         ...

3. Mark those of your handlers parameters which are to be injected with FromDishka[]

@broker.subscriber("test")
async def start(
    gateway: FromDishka[Gateway],
):
    ...

3a. (optional) decorate them using @inject if you are not using auto-injection

@broker.subscriber("test")
@inject
async def start(
    gateway: FromDishka[Gateway],
):
    ...

4. (optional) Use FastStreamProvider() when creating container if you are going to use faststream.types.StreamMessage or faststream.ContextRepo in providers

container = make_async_container(YourProvider(), FastStreamProvider())

5. Setup dishka integration. auto_inject=True is required unless you explicitly use @inject decorator

setup_dishka(container=container, app=app, auto_inject=True)

Or pass your own inject decorator

setup_dishka(container=container, broker=broker, auto_inject=my_inject)

FastStream - Litestar/FastAPI - dishka integration

1. Running RabbitMQ

docker run -d --name rabbitmq \
  -p 5672:5672 -p 15672:15672 \
  -e RABBITMQ_DEFAULT_USER=guest \
  -e RABBITMQ_DEFAULT_PASS=guest \
  rabbitmq:management

2. Example of usage FastStream + Litestar

import uvicorn
from dishka import Provider, Scope, provide
from dishka import make_async_container
from dishka.integrations import faststream as faststream_integration
from dishka.integrations import litestar as litestar_integration
from dishka.integrations.base import FromDishka
from dishka.integrations.faststream import inject as faststream_inject
from dishka.integrations.litestar import inject as litestar_inject
from faststream.rabbit import RabbitBroker, RabbitRouter
from litestar import Litestar, route, HttpMethod


class SomeDependency:
    async def do_something(self) -> int:
        print("Hello world")
        return 42


class SomeProvider(Provider):
    @provide(scope=Scope.REQUEST)
    def some_dependency(self) -> SomeDependency:
        return SomeDependency()


@route(http_method=HttpMethod.GET, path="/", status_code=200)
@litestar_inject
async def http_handler(some_dependency: FromDishka[SomeDependency]) -> None:
    await some_dependency.do_something()


amqp_router = RabbitRouter()


@amqp_router.subscriber("test-queue")
@faststream_inject
async def amqp_handler(some_dependency: FromDishka[SomeDependency]) -> None:
    await some_dependency.do_something()


def create_app() -> Litestar:
    container = make_async_container(SomeProvider())

    broker = RabbitBroker(url="amqp://guest:guest@localhost:5672/")
    broker.include_router(amqp_router)
    faststream_integration.setup_dishka(container, broker=broker)

    http = Litestar(
        route_handlers=[http_handler],
        on_startup=[broker.start],
        on_shutdown=[broker.stop],
    )
    litestar_integration.setup_dishka(container, http)
    return http


if __name__ == "__main__":
    uvicorn.run(create_app(), host="0.0.0.0", port=8000)

Example of usage FastStream + FastAPI

from collections.abc import AsyncIterator
from contextlib import asynccontextmanager

import uvicorn
from fastapi import APIRouter, FastAPI
from faststream.rabbit import RabbitBroker, RabbitRouter
from dishka import Provider, Scope, make_async_container, provide
from dishka.integrations import fastapi as fastapi_integration
from dishka.integrations import faststream as faststream_integration
from dishka.integrations.base import FromDishka
from dishka.integrations.fastapi import DishkaRoute
from dishka.integrations.faststream import inject as faststream_inject


class SomeDependency:
    async def do_something(self) -> int:
        print("Hello world")
        return 42


class SomeProvider(Provider):
    @provide(scope=Scope.REQUEST)
    def some_dependency(self) -> SomeDependency:
        return SomeDependency()


router = APIRouter(route_class=DishkaRoute)


@router.get("/")
async def http_handler(some_dependency: FromDishka[SomeDependency]) -> None:
    await some_dependency.do_something()


amqp_router = RabbitRouter()


@amqp_router.subscriber("test-queue")
@faststream_inject
async def amqp_handler(some_dependency: FromDishka[SomeDependency]) -> None:
    await some_dependency.do_something()


def create_app() -> FastAPI:
    container = make_async_container(SomeProvider())

    broker = RabbitBroker(url="amqp://guest:guest@localhost:5672/")
    broker.include_router(amqp_router)
    faststream_integration.setup_dishka(container, broker=broker)

    @asynccontextmanager
    async def lifespan(app: FastAPI) -> AsyncIterator[None]:
        async with broker:
            await broker.start()
            yield

    http = FastAPI(lifespan=lifespan)
    http.include_router(router)
    fastapi_integration.setup_dishka(container, http)
    return http


if __name__ == "__main__":
    uvicorn.run(create_app(), host="0.0.0.0", port=8000)

Testing FastStream with dishka

Simple example:

from collections.abc import AsyncIterator

import pytest
from dishka import AsyncContainer, make_async_container
from dishka import Provider, Scope, provide
from dishka.integrations import faststream as faststream_integration
from dishka.integrations.base import FromDishka as Depends
from faststream import FastStream, TestApp
from faststream.rabbit import RabbitBroker, TestRabbitBroker, RabbitRouter

router = RabbitRouter()


@router.subscriber("test-queue")
async def handler(msg: str, some_dependency: Depends[int]) -> int:
    print(f"{msg=}")
    return some_dependency


@pytest.fixture
async def broker() -> RabbitBroker:
    broker = RabbitBroker()
    broker.include_router(router)
    return broker


@pytest.fixture
def mock_provider() -> Provider:
    class MockProvider(Provider):
        @provide(scope=Scope.REQUEST)
        async def get_some_dependency(self) -> int:
            return 42

    return MockProvider()


@pytest.fixture
def container(mock_provider: Provider) -> AsyncContainer:
    return make_async_container(mock_provider)


@pytest.fixture
async def app(broker: RabbitBroker, container: AsyncContainer) -> FastStream:
    app = FastStream(broker)
    faststream_integration.setup_dishka(container, app, auto_inject=True)
    return FastStream(broker)


@pytest.fixture
async def client(app: FastStream) -> AsyncIterator[RabbitBroker]:
    async with TestRabbitBroker(app.broker) as br, TestApp(app):
        yield br


@pytest.mark.asyncio
async def test_handler(client: RabbitBroker) -> None:
    result = await client.request("hello", "test-queue")
    assert await result.decode() == 42